Hello, everyone. I would like to welcome you and thank you for attending today's webinar, DNA and Sexual Assault Cases Part 1, an Introductory. The webinar is being brought to you through IFN's Technical Assistance Project. We are grateful to be able to host Dr. Julie Valentine and Rebecca Kaye for today's webinar. Please advance. My name is Gail Horner, and I am one of the Forensic Nursing Specialists with IFN. Please advance. I would like to share a few housekeeping items with you today before we begin. Today's webinar is possible due to funding provided through the Office on Violence Against Women, and the presenters of today's webinar disclose no conflicts of interest. If you have multiple people watching today's webinar with you, please send a list of all attendees that have not formally registered for the webinar to this email address, and I will type it in the chat, SAFETA at ForensicNurses.org, and share the evaluation link with them. As a benefit of membership, IFN members are eligible to receive 1.5 contact hours for this continuing education activity. The IFN is an approved provider of continuing nursing education by the American Nurses Credentialing Centers Commission on Accreditation. For IFN members to obtain CE for this activity, they are asked to attend the webinar in full and complete the post-activity webinar evaluation to obtain a certificate documenting the contact hours for this activity. For non-IFN members, with the completion of the post-activity webinar evaluation, you will receive a certificate of attendance. This webinar is being recorded today and will be available on the SAFE TA website for viewing at a later date. IFN will send an announcement to all registered attendings once the webinar is available for viewing. Next slide, please. I would like to introduce today's presenters to all of you. With us, we have Dr. Julie Valentine. Dr. Valentine is the Associate Dean of Undergraduate Studies and Research and an Associate Professor at Brigham Young University College of Nursing. She's also a certified adult adolescent sexual assault nurse with Wasatch Forensic Nurses. Her clinical specialty and research focus areas are sexual violence, intimate partner violence, and criminal justice system response to sexual violence. She conducts research to inform interdisciplinary practice and policy and improve criminal justice response in sexual assault cases. Dr. Valentine and her research team currently have multiple research studies utilizing their large growing database of 9,000 sexual assault cases. They're keenly aware that each sexual assault case represents an individual who suffered sexual assault trauma and strive to represent these survivors' voices. Dr. Valentine is also a primary author of three awarded federal grants since 2015, totaling $3.45 million. She is the primary investigator on several studies related to sexual assault. Dr. Valentine has served in leadership roles with the International Association of Forensic Nurses from the Utah chapter president to director at large on the International Board of Directors. She is also the lead author of the Constructed Theory of Forensic Nursing Care to Guide Forensic Nursing Education, Practice, and Research. And in 2015, Dr. Valentine was appointed to the Sexual Assault Forensic Evidence Reporting Act Committee to develop the national best practices for sexual assault kits, a multidisciplinary approach to guide national policies. She has served as an expert in multiple legislative bills related to sexual assault and domestic violence. Next slide, please. And then presenting with Julie, we also have Rebecca Kay. Rebecca is a forensic biologist and senior manager over the biology section of the Utah Bureau of Forensic Services. She has worked as a forensic scientist for the past 18 years in both private and public forensic laboratories and has provided expert testimony in Utah, Arizona, and Nevada. Since joining the Bureau of Forensic Science in January of 2008, Rebecca has held positions of senior forensic scientist, DNA technical leader, and manager of the Homicide High Throughput and DNA Technical Teams, and she has played an integral role in bringing new technologies and testing capabilities to the Utah Bureau of Forensic Sciences, including more sensitive testing measures such as YSDR analysis and DNA sequencing. She is an appointed member of the OSAC Human Forensic Biology Subcommittee and the Utah Cold Case Review Board. She teaches forensic science courses for Southern Utah University and holds a Master of Science degree from the University of Florida. And if it's okay with the two of you, I will turn it over to you so we can get started. Welcome, everyone, and Gail, thank you for those introductions. After reading that, I thought, oh, that was long, but I hope a big takeaway immediately that all of those listeners have is that as I am presenting with Rebecca throughout this entire presentation, a big takeaway is highlighting the importance of the collaboration between forensic nurses and forensic scientists, how necessary that is in approaching these cases. We are doing two presentations on DNA. This first one is more basic. It's an introduction. We will go through exactly, after we collect evidence in the box, the kit, and that is given to law enforcement and taken into Crime Lab, what happens. The next presentation that we will be doing, part two, will get a little more into detail about research, about what impacts DNA, development of a probative DNA, profile in sexual assault cases that can help inform our practice, and some potential new technologies out there. I'm very grateful to be presenting with Rebecca today and grateful for this opportunity. The views presented here are mine. I want to acknowledge Utah Bureau of Forensic Services, which is our state crime lab. We have had a collaborative relationship for many years on research since 2011, and a great collaborative relationship between Utah Bureau of Forensic Services and forensic nurses throughout the state, including Wasatch Forensic Nurses. The learning outcomes are four. We want you to get a sense, a better understanding of the history of forensic DNA and implications of use, specifically in sexual assault cases. Rebecca will go through forensic DNA terminology so that you feel more comfortable with these terms and have a better understanding about what they mean, as well as the general laboratory steps. We encourage you to contact your forensic scientist, your lab, and learn more about their steps, because there are some variations between labs. And then also to recognize and evaluate best practice recommendation and evidence collection techniques to optimize the DNA analysis findings, and we will end with three case studies. That discussion, after we went through those, feel free to put in the chat, what are you most excited to learn about? What do you feel is going to most impact your learning today? All right. I am a big believer in know your why. I think that knowing our why in everything we do makes what we do more meaningful and helps direct our actions. So when we consider our work as forensic nurses, specifically our work in doing sexual assault medical forensic examinations in sexual assault cases, I hope that you think before you see every patient, before you start each day, why do I do this? And why do I do what I do when I'm there taking care of patients? First, we are nurses. And happy National Nurses Week to everyone out there. I hope you feel a bit celebrated this week. But our primary response when we are called in to see a patient who has experienced sexual assault is to provide health care. And I think we are all in agreement of that. Part of that health care is across the whole spectrum of that person's needs. So a very holistic approach. All of us employ many aspects of psych nursing and caring for patients and providing resources along with that health care. But that is our primary responsibility. We have education to be trauma informed. I think this is one of the greatest things about as we have expanded the length of time that we are seeing patients between experience of sexual assault and getting an examination. That then means that it opens up that we see more patients, meaning we can provide trauma informed services to patients to hopefully at the examination, our hope is that it can begin a process of healing for these patients. We know that these examinations are invasive. I think we all strive to make them, although they are invasive, to make them a beginning of healing for our patients. We are very patient or survivor focused. We all know the importance of providing education to our patients about these examinations, what to expect, all in the context that they have control over the examination. At any point, they can stop the examination. They have control if they want to talk to law enforcement or not talk to law enforcement. They have control over what is collected or not collected. They have control over the photograph. We know that when we give patients a sense of control, that is a very healing process and so important that we are very patient survivor focused. We also know, for those of you listening, frequently we have very little background on the patients that we are called in to see. You can get paged and see a 14-year-old who was sexually assaulted at a party. You could see an 85-year-old who was sexually assaulted at a care facility. We also see so much intimate partner violence. Because our landscape is so varied on the experiences of our patients and the trauma that they have experienced, this job really requires expertise in clinical judgment. When we look at best practice recommendations, we need to always consider that those best practice recommendations are interpreted also with a high degree of clinical judgment. Number one reason we do these exams is about the patient and about providing health care and hopefully starting or adding to that healing of the patient. What about the box? We also are there if the patient consents and wants to have evidence collected. We are there as a forensic evidence collectors who collect this evidence that is then handed off to the forensic evidence analysts or specialists. We should work very collaboratively between our crime labs and the forensic scientists in the crime lab because how we collect the evidence and our communication about that evidence can impact their choices perhaps on the analysis techniques or testing. We need to have really clear communication as we are working together. The big picture, this is a constructed theory of forensic nursing care. Forensic nursing care informs, impacts, and the goal is improves the most important thing is patient health outcomes. When we consider patient health outcomes, we think short-term outcomes, maybe from the time they come in for the exam to the end of the exam through the next few days to long-term health care outcomes. That's an area where we need a lot more research. Long-term, how does our care impact patients' recoveries? You'll see the two other boxes are also important, but not the most important, but the other ones are forensic evidence outcomes, how we collect this evidence, our practice techniques, impact the forensic evidence outcomes, which also intersects with the criminal justice outcomes. When we testify in court, that also will impact the criminal justice outcomes. So all of these work together. Today's webinar focuses on primarily that smaller box of forensic evidence outcomes. With that, I am going to turn these slides over to Rebecca for presenting. Thanks, Julie. She's also the one to advance my slides, so stick around. Feel free to add anything as we go through this. As far as DNA analysis, as we know it, goes back to 1984. In a historical perspective, it is still very new. The technology is changing all the time. From the time of Alec Jeffries discovering what was termed DNA fingerprinting, the technology has advanced very quickly. We can do so much more now with so much less sample that it truly is amazing. Every time we bring new technology online, we're already looking at what the next thing is. We're never not looking forward in DNA because it is literally changing constantly. We'll go through and explain how that DNA fingerprinting of the late 80s is a bit different than what we're doing today, but ultimately is giving us that same information, which is looking at a DNA profile on evidence and attempting to either exclude or include a particular individual as being the source of the DNA that's discovered on the evidence. You can move forward, Julie. A few of the definitions that Julie mentioned in the beginning is trace or touch DNA is a big one right now. These terms are often used interchangeably, but what we mean is a very small amount of DNA that may be left behind that is not necessarily associated with any type of biological fluid. This is the type of DNA left behind as you touch any surface or object or make contact with an individual and skin cells are shed and left behind on the surface. When we refer to touch or trace DNA, the amount of DNA that we have to work with in those samples is very low compared to, for example, seminal fluid or a blood stain where the amount of cells and DNA left behind is often abundant and we can do much more with. Short tandem repeat or STR DNA is the type of DNA testing that is routinely done in all crime laboratories at this point in time. It is looking at very small repeated segments of DNA in specific areas along the chromosomes that we know differ between individuals. The vast majority of all of our DNA is exactly the same, but we know there are areas where people differ. One of these areas is called a short tandem repeat. It's a short segment or sequence of DNA that is repeated multiple times in tandem. What differs between people is the number of times that sequence is repeated. Again, we're looking at very specific locations where we know these are located and that's what we're targeting for our typical DNA analysis that is conducted on evidence. The Y-STR DNA is then similar locations. We're looking again at STR DNA sequences, but they're all located on the Y chromosome. And so, therefore, these are only available to be tested in males who have a Y chromosome. It is a way that we can ignore the female DNA in a particular sample and really hone in on any male DNA that may be present. The reason this can be really important is in mixtures, mixtures of DNA from multiple individuals. So, in a scenario where you have a female victim and we're looking for maybe trace DNA or very low levels of DNA that are left behind by a male contributor, traditional STR analysis may not provide information from that male contributor. We are bound by some limitations of the technology and the instrumentation. If one individual in a mixture leaves 20 or 50 times as much DNA as another contributor, their signal sort of swamps out any signal from that lower level contributor, the person who left the smaller amount of DNA. And so, even though there may have been cells present from that individual, we won't detect any signal from the short tandem repeat analysis. This is a scenario where we could use YSTR testing technology, we ignore the higher amount of DNA or cells left behind from the female contributor, and just hone in on those areas on a Y chromosome and, therefore, the DNA of the male contributor where we can actually still develop a YSTR profile and use that for comparison purposes. Okay. Next slide. Some additional definitions. When we talk about forensic serology, we're talking about screening evidence for the presence of biological fluid. Most crime laboratories will be doing routine testing for things like human blood, seminal fluid, saliva. Additional types of tests that may be used in some crime labs may be testing for urine or fecal material or something like that could be left behind. Why screening? Have another slide that shows how all of these go together. Why screening is a term where during the screening process of evidence, so during that forensic serology portion, they can actually take a very small amount of the evidence and do a real-time PCR, which we'll get into as well, but they take a very small amount and they're really looking to see, is there any male DNA present in the sample at all? They can use that information to screen a bunch of different evidentiary samples and determine which ones should therefore be sent to full DNA analysis. So it is a screening tool looking specifically for male DNA and used in those scenarios where, again, you have a female victim and a male assailant because what we're really looking for are what are the best samples to send forward to DNA, seeing that. DNA extraction is the first step in the DNA process, and this particular step, we're simply breaking cells open to get the DNA into solution so that we have it to work with. The quantitation step is a step where we, again, are using real-time PCR, so a process similar to what's used in why screening, but in this case, you're taking that full amount of the evidentiary sample that you're going to use in the DNA process, not just a little snip of the overall evidence, but now you're taking that larger portion that you will use in your DNA analysis, and you get an estimate of the amount of human DNA present in your sample as well as an estimate of the amount of male DNA that you have in your sample. It also gives us some additional information, sometimes information on whether the sample is degraded, which can, again, affect downstream what our data may look like, and it gives a glimpse up front of what we expect downstream in the resulting DNA profile. Okay, next. Additional definitions will revolve around CODIS. Currently, we are trying to get profiles into CODIS for multiple reasons. If there is an unknown perpetrator, getting a DNA profile from that individual and putting it into CODIS, which is the Combined DNA Index System, allows us to do a search of that database to see if we can identify the individuals we have on the evidence, and in that way provide an investigative lead with an actual individual to report back to law enforcement so they can then take their investigation in that direction. Another part of having a search in CODIS is that we can link forensic cases, so whether or not we know who the perpetrator was in any particular case, if we put the evidentiary profile into CODIS, it may hit to another case where the same individual's DNA was found, and in that way we can link cases together. This can be really important because law enforcement between different agencies don't always communicate really well, and so this is a way for us to give a heads up to one law enforcement agency to say, hey, you know what, the same person that is involved in your case was involved in a case a county over or a state over or the other side of the country. And so then it gets them to be able to talk and work together to make sure those cases are linked and potentially solved. So when we talk about CODIS eligibility, there's a couple of different things that play into that determination. One is the scenario of the particular case, as well as the evidence that's found. So we have to ensure that the case scenario is CODIS eligible. We also have to ensure that the profile that we're entering came off of a piece of evidence directly related to that case and is therefore probative. Additionally, once we develop the DNA profile, there are some thresholds that have to be met in the data to make it eligible just based on how full that profile is. Do we have enough information? Is it something that if searched in the database is going to provide usable matches? And so we have the case and evidence side of eligibility, but we also have the data driven side of how good the data is and whether or not it's eligible on that side. And then, as I said, hopefully what results once you put a profile into CODIS is what we call a CODIS hit, meaning we've provided some link to either a known person, potentially a convicted offender who has been collected for the database, or even another case that can link them directly to cases together. Julie? In our laboratory, we are set by a lot of not just guidelines, but standards. We are held to national and international standards for processing of DNA evidence. And a lot of that starts right back to the basics, which I'm sure you all as nurses are familiar with, but using personal protective equipment to be very cognizant of clean technique. We have to ensure that samples are not touching each other, that we are not having a sample to sample contamination or contaminating things with the environment or ourselves. And so we are often, not often, we are always wearing personal protective equipment. Minimally, we will be wearing a lab coat, gloves, and a face mask. As I said, the DNA technology is incredibly sensitive right now and seems to continue to get more and more sensitive. We have to be very careful with ourselves over the evidence and make sure that we are not contributing to any DNA that may be found on a piece of evidence. This includes using sterilization techniques, such as a UV cross-linker. We do use a 10% bleach solution, and we're cleaning between each item of evidence that we open, cleaning the entire lab bench, ensuring that all of the tools that we're using are cleaned and sterilized, including, as I said, 10% bleach, ethanol. We're putting down new butcher paper between each one and throwing that away so that it's not even laying on the same surface that another piece of evidence was. And then the UV cross-linking is important because it basically renders any DNA that may be left on an item, maybe a tool or an instrument, useless. So we clean them the best of our ability, but just in case there's something that could be left behind, the UV cross-linker will actually take the two strands of the double helix and bind them together in a way that they can't be separated anymore. And without that separation of those two strands, our process for DNA analysis at the laboratory can't take place. And so in this way, we render any DNA that may be left behind untestable and not detectable. And again, with using all of these techniques, we're trying to ensure that there is no contamination, no cross-contamination, and making sure that we're taking those samples forward in a very clean way so that we're only detecting the DNA that was left on the evidence that you actually collected. The separation of lab space I can show best in the next slide. This is the overall space that we have here in our laboratory at the Utah State Crime Lab, but all laboratories will have something similar. We try to have a one-way flow of traffic through the laboratory because it is incredibly important that circle at the bottom, that AMP and CE room where we've actually created a lot of copies of the DNA in a particular sample, we have to ensure that anything from that room does not go back into that upper extraction area, or even into the serology lab, because those amplicons, as we call them, would create terrible contamination if they got back onto evidence because they will be more easily tested and copied the next time around. And so in our process, one of the steps is called amplification, which I'll take you through the whole thing, but amplification, we're using PCR, we're creating millions of copies potentially of specific targets of DNA, those STR locations, and so because there's so much DNA at that point, once we've made all those copies, we do have to keep those isolated, and that is one reason for, you can see in the middle of the lab there's that vestibule. We can go from the extraction area into the vestibule. We're going to change, we're going to have different coats on, different gloves on, we're changing all of our PE at that point. We go into the AMP room, and then we have one-way flow. That door doesn't even have a handle to be able to go back out the other direction, back into the extraction area. So once you're in the AMP room, you have to exit where you see at the bottom of the screen because we don't want any of that flow going back into extraction or into the serology portion of the laboratory. Next. So the basic case flow, as I said, items are submitted for evidence. It first goes through what is called screening or forensic serological analysis, where we're testing for biological fluids, or some laboratories under some conditions or certain cases may determine that they don't need to screen or test for biological fluids, but they take the sample and they go straight to DNA. So they just cut the portion needed and go straight into DNA analysis without testing for biological fluids. And so that is something that is determined by the laboratory. Each laboratory does their own validations. They have their own case and sample flow. And so under certain conditions, they may determine you don't need to necessarily show that this particular red brown stain is human blood, because if we take it forward to DNA and we develop a profile, a DNA profile, then it points to the fact that at least it was human DNA. It's a red brown stain. Do we really need to know that it's blood or do we just need to know whose DNA is there? So there are different kind of case and sample flows for different laboratories or potentially the same laboratory may have a different flow for different items of evidence. In Utah, we do have a direct to DNA approach for not only sexual assault collection kits from adults, but also from a lot of our property crime evidence where we if we're swabbing, let's say the mouth of a bottle, we don't then test for saliva to identify that before going straight to DNA. We just swab the mouth area of a bottle and we go straight to DNA. So a lot of those decisions, again, are going to be lab specific. Each lab will make their own determination because all of the evidence comes in on swabs for a sexual assault kit. For the most part, we have a very high throughput approach in our laboratory and we will cut up to half of each of the items collected and send it straight to DNA. We perform a type of extraction that allows us to separate any spermatozoa that may be present from all the other epithelial cells. And so if there is seminal fluid present in there, at least with spermatozoa, that we'll be able to separate those prior to DNA. So each sample is processed as though it does have seminal fluid present, but we don't stop and test for seminal fluid on every single swab and then blood on every single swab and then saliva on every single swab. We literally choose our best samples, cut half of them and take them straight to DNA in those instances. In the children cases, we do screen more because it may be very important to know that we found saliva on the labial swabs along with some other individual's DNA and not just go straight to DNA. It may help to at least infer different things that occurred. It really does depend on the case and the scenario. Then it goes to DNA analysis where we did hopefully develop a profile from a foreign contributor to the victim and we'll issue a report with any comparisons that we do to known individuals, as well as provide a statistical analysis of the strength of any batch that we can report. Next slide. I think those goes back. Well, maybe not. Sorry. This is about how we choose our swabs in Utah. As I said, we have a straight to DNA approach. What we do is we read the history that's presented in the nurse's exam report. We look at which swabs from which areas were chosen to be collected by the nurse. We look at their notes. We look at what they wrote the victim's account was of the actions that occurred. Then we have our own practices and policies within our laboratory, our own standard operating procedures that help us to determine under these conditions, with these activities, with what the nurse has documented, what are the samples that are most likely to develop a probative profile DNA wise that we can use downstream. That might be three, four, five different samples that we take forward potentially from each sexual assault kit, but we do that initially. That is our first pass of the kit. If that does not answer the questions and we don't develop a profile, we can always go back to the remaining swabs and do additional testing if needed. We start, as I said, we have a very high throughput approach where we are attempting to maximize some robots that we use in the laboratory that can work up to 96 samples at a time. We're trying to just get that, our best chance of getting a profile, our best judgment in which samples are most likely to contain enough DNA in a profile. We send those forward and then can reassess once we get the data off of that of whether or not additional work is needed. Next slide. As I said, in serology, we are looking to potentially choose the best samples moving forward and sometimes part of choosing does require serological testing. Each laboratory will determine, do they test swabs up front for biological fluid? Do they test all swabs? Do they test a subset of swabs? Again, that's going to be something that each laboratory is determining their flow, their case flow and how those are processed. Once they do test, if they do test for serological results, they will use those results of the test. They can potentially be using that Y screening type test results where they take, again, a very small snip. We also have to take small snips for each of the fluids that we're trying to identify if we do test for biological fluid. You can see how the more testing you do up front, you're using some of the sample. This is one of the reasons that we have gone to a direct DNA approach for some of these cases is because we don't want to use that sample up front. We'd rather maximize how much sample could go downstream. But it is a balance and there is good information that can come out of testing, just like there is a good reason to try to keep enough to develop a profile and so it really is a balance. Typically, only half of each sample, up to half of each sample is taken for DNA testing. This is to leave the other half of the sample for the defense if they want to have their own laboratory or do any kind of retesting on the sample. It also saves half for future use in case a new technology comes out that is more sensitive where you didn't get a result this time around, but maybe saving half of that evidence for the future might provide answers if we can't develop those answers today. Next. This is the flow through the laboratory of the DNA process. So again, in serology, you can either have that full serological testing or cut straight to DNA. The next main step is extraction, but I threw that Y screening in there as an optional step. So oftentimes, if the laboratory does employ Y screening, that's going to be part of serology or the serology section where they're going to take that additional snip, see if there is any Y DNA or male DNA present in that sample to determine if we're going to send it for full DNA analysis. Other laboratories, they simply do the serological testing or the cutting of the sample and they go straight through the DNA process. So the first step in the DNA process is DNA extraction. There are many different types of extractions that can be employed. Some of them are more hands-on, some of them are more robotic, but basically, we're breaking the cells open, including the nucleus, to get the DNA into solution, and then there's often some wash steps involved here where we're going to get rid of the cellular debris, get rid of the proteins from the cells, and just leave a clean DNA sample solution. That's what we call our DNA extract. That DNA extract is then sent for quantitation. Quantitation is, as I said, a real-time PCR. So as each cycle of PCR goes through, it's going to be placed on a graph of how many times or how much signal it is receiving, and in this way, because of the probes that are used, we can have an estimate of how much human DNA is in that sample versus how much male DNA is in that sample. This is a step where decisions are made. So the results of quantitation tell us, is there any male DNA present? And if not, and we have a female victim and we are looking for a male perpetrator, maybe that sample is going to stop right there. It means there's no DNA present from a male. It doesn't need to go forward for a full DNA profile. I might stop it right at that step. Another thing this tells us is, do we have enough DNA to develop a DNA profile? This is a level that each laboratory should have validated or they should know for their system, and so this step allows them to know that. Another thing this step allows us to figure out is that ratio of female to male DNA in each sample. As I said, if there's 20 to 50 times as much DNA from one individual as another, and we do traditional STR DNA testing, we're not going to even detect the profile of that, what we call minor contributor, the person who left the lower amount of DNA. And so in this scenario with quantitation, if I can see that my human DNA amount is really high, and it's more than 50 times the amount of male DNA or Y DNA that I'm detecting, I already know sending it forward for traditional STR DNA analysis is not going to result in a profile from that male contributor that we're looking for. And so it would be a decision point where I'd say, ah, Stop this sample here. This needs to go to YSTR analysis and that is a different pathway. It uses different probes and we're targeting different areas. And so this is a major decision point at quantitation for the laboratories to determine how each sample moves forward or if it moves forward. Next. So once I know how much DNA I have to work with, we can set up our amplification reaction. And that amplification is using PCR. So we target those specific areas where we know STRs are located on the DNA and on the chromosomes. And we copy those. It's like a molecular Xerox machine. We're going to make exact copies of those very specific areas of DNA where we know people differ. Another part of the PCR process is every time it's creating one of those copies, it's attaching a fluorescent tag. A very specific one which will be used further down to detect that fragment during the separation and detection step, which is next. So we will separate all of the fragments that we've made by size and by tag color. This allows us to figure out the number of repeats that would be on that fragment. And it allows us to size against a known set of fragments that we call a ladder. And so as those fragments are separated through what's called capillary electrophoresis, it's basically a very thin long capillary tube that's filled with a polymer, which works a bit like a sieve. So the smaller fragments travel faster through that. And the larger fragments travel slower. And so as you put electrical gradient across, the DNA moves through that capillary. And there is an LCD camera and laser. And as it passes by there, it excites that fluorescent tag that was added. And we not only then know how many repeats or how large that fragment was, but exactly which location on the DNA it's associated with based on that fluorescent tag. So once we've separated and detected all those fragments, we get our data in the form of a graph called an electrophorogram. We can then do the data analysis, any troubleshooting that needs to be done on the sample to get, you know, better results, higher results, can be done at that point. And we determine the resulting profiles, the DNA profiles of the individuals that we can, that were present on the evidence. And then it goes to what we call interpretation and comparison. This is where we are interpreting those profiles. We are determining if it is DNA that came from one person, or is it a mixture of two people, or maybe three people. We compare those resulting profiles to the profiles from known individuals who may have been collected. I'm not sure how they do it in other states, but in our state, the forensic nurse examiners are collecting consensual partners if they're present at the exam and they're able to be collected. And they put that right in the sexual assault collection kit for us, which is incredibly helpful. So we usually have a standard, at least from the victim, as well as any consensual partner that maybe was present and collected. And then if the law enforcement agency was able to collect anything from a suspect, we would have that as well. So we can make those comparisons to the evidence profiles. And then, as I said, if we can exclude individuals, we are always looking to exclude. If we can't exclude because they're consistent at every location, then that is there for an inclusion or a match. And any time that we have an inclusion or match, we must give a statistical weight to the strength of that inclusion or match. That is an international standard. That's a must for any laboratory. We cannot issue a report that just says, yep, those two are match, or they're the same, or it came from him. That is not allowed. We have to say, no, they are included, or maybe there's a match, but here is the strength of that match. Because if they match and have very rare alleles, it might be a higher statistical weight, but we have to provide that in our report. Next. Extraction, I've already explained where we're breaking it open, putting it into solution, having some of those washes of the DNA to make sure it's nice and clean. We remove inhibitors and other cellular debris. These are just some instruments that may be used in this process. I also mentioned very briefly that there's a technique where we can separate spermatozoa from all other epithelial cells in a sample. And in Utah, all of our sexual assault kit evidence goes that route, just in case there are spermatozoa present. It's what's called a differential extraction. And it's a process that we do up front before we actually break open cells. What we do is add a very mild detergent to the sample, which will actually break open epithelial cells, but it will not disrupt the spermatozoa, the heads anyway. And it is in the head where the DNA is located. So sperm capsules of the head are very hardy, where the mild detergent disrupts the cell membrane of an epithelial cell, it will not do anything to the head of the spermatozoa. So we can add that first and then centrifuge the sample and pellet all the sperm to the bottom of the tube. We can then take the liquid off the top that has all of the DNA that has been broken out of the epithelial cells, put that in a separate tube, do some additional washes of what we call that sperm pellet, and then we can use a harsher chemical to break open the sperm heads. So they're in a separate tube. And in that way, we're already separating potentially the male DNA from the female DNA in a particular sample. That separation only works if spermatozoa are present. We do not have a technology yet that allows us to separate epithelial cells from different individuals. So that differential extraction really limits us to only those where spermatozoa may be present. And that is actually that first instrument on the left. It is called a kya cube, and it is actually an automated way to perform that differential separation prior to extracting the sample. It can also be done manually. And so a lot of laboratories do it manually. Some also will be using things like the kya cube to automate the process and get a little more high throughput. The instrument in the center is called a starlet. This is a robot that does a lot of pipetting and liquid transfer. And so this is the robot that we use to perform the actual extraction from our high throughput team. So it'll go on that kya cube, that first instrument. And once we have the differential separation, we put it on the starlet to complete the rest of the extraction process. The instrument on the right looks a little bit like an easy-bake oven, and that's what we like to refer to it as sometimes. This is called a Maxwell instrument, and it does perform DNA extraction very hands-off other than setting the thing up to begin with, but performs a lot of those wash steps of washing the extract to make sure we have nice, purified DNA at the end. And you can do up to 16 samples at a time on that instrument, where the big one in the middle, that starlet, you can do a 96-well plate of samples. And so it just depends on the individual laboratory and the instrumentation they may use, but it all has a similar process. And again, the result is the same, where we want to get that purified DNA in liquid form. Next. This is the real-time PCR instrument, or this is one of the newer ones. It's called a quant student. There are still some other instruments available as well, so this is not the only one. But it's performing that real-time PCR. It's always attached to a computer, and it's going to give us, again, that ratio, ultimately, of female to male DNA, so that we know how to proceed with each sample and can even determine what the outcome might look like of that resulting profile if we take it the rest of the way through the process. Next. This is a thermal cycler. So this does the same thing as the instrument previously, but it doesn't give us any real-time data. It doesn't give us data after every cycle of PCR. This one's programmed to do all the cycles of PCR, and we get the result of amplified DNA that we can put onto the instrument to separate those fragments. And so, again, this is going to make copies of very specific locations where STRs are present, and it's going to attach those fluorescent tags as it copies the DNA. Each new fragment will have that fluorescent tag attached. Next. So we did talk about STRs. This is probably an easier way to see that. STRs, those short tandem repeats, it's that area in the sequence that you see there of Cs and Gs and Ts and As, that orange area, you can see is repeated the sequence GATA multiple times in tandem. The more times you have that sequence repeated there, the longer your resulting fragment is going to be. For example, the 13 repeats at the bottom that you see on the lowest level. The fewer times you have it repeated, the shorter your fragment. And this is why we can separate these fragments by size, and that truly gives us the information we're looking for. We are only looking at fragment size. With STR testing, the current methods that are used in all forensic laboratories is only looking at the size difference of fragments. It is not actually going down and reading the code as you see written there. We are only extrapolating. If the fragment is this big, it lines up with 12 repeats, so that person has it repeated 12 times. Not what the actual GATA sequence is, just simply separating by size. This information is what is put into CODIS, the STR profile. It is just a set of numbers of how many times you have that sequence repeated at every location. It does not predict disease. It does not predict phenotype. We can't tell anything about the individual from this profile other than whether or not they're biologically male or female as far as having two X chromosomes or an X and Y chromosome. That is the amount of information that we get out of this type of profiling. It's simply used to identify an individual and tell people apart, and that's the extent of it there. Next. This is the Y chromosome. Each of those DYS numbers you see there is a specific location of an STR on the Y chromosome. I think there's more to this if you go forward. So YSTR analysis will target these areas where we know there are STRs located just on the Y chromosome. As I said, and as males only have, only males have a Y chromosome, and it is inherited as a full unit from father to son. We don't have on the Y chromosome another one or two copies, and so because of that, there isn't that random assortment that happens with the other chromosome pairs. With the Y, it's going to be inherited straight from father to son to grandson, which means that the YSTR profile for any male is not unique to that male, but really does fall within that familial line. So if you have two brothers that share the same father, they will, all three of them, have the exact same YSTR profile. Where STR profiles are unique to the individual other than identical twins, YSTR profiles travel a family line, and in that way, that strength of a match is not as statistically significant. It is still significant, and there's still meaning behind it, but there is more that has to be involved on the investigative side, because they do have to rule out things like their brother in the same area at the same time, and help to link an individual to something that is actually running through a whole family. But again, super, super helpful in those extreme mixture cases where you have an abundance of male, or sorry, abundance of female DNA, and you're looking for that very small amount of male, STR testing will get us anything, but Y's gives us something to compare to, and so it is very useful and important in those cases that need it. Next. This is the capillary electrophoresis instrument, and within that window that is highlighted in blue there is where that big capillary will be placed. It used to be in these CE instruments that you had one capillary, and you could literally process one sample at a time, and then they increased it to four, then it increased to eight, and we now have one instrument that has 24 capillaries, and so when you're running a plate of 96 samples in four injections, we can get all 96 samples through this instrument, and so again, we're just increasing the capabilities, not just the sensitivity, but the throughput. Our turnaround times are dropping so that we get information back in a much, much more efficient way, and that graph that you see on the lower left is the type of data that we're getting out of this instrument. In this case, what you see there is that ladder that I talked about. Those are fragments of known sizes that can be used basically up against your evidentiary profile to know exactly how large each of those resulting fragments in the profile are based off of this ladder. Next. So when we look to do interpretation, as I said, the first thing we have to do is say, is this DNA from one person or multiple people's sample put together? So is it single source, or is it a mixture of DNA from multiple people? And if it is a mixture, how many people are in there? Once we know how many people are in there, we have to estimate the ratio of the amounts of DNA of each of those people. So is it a mixture of five to two to one? Is it a one to one? Each of those we can see in the data as the height of those peaks that we see off of the capillary electrophoresis instrument correlates to the amount of DNA left behind. And so we can look at the balance of peaks, how many peaks, and try to tweeze some of this information out, which is really important for us to do prior to comparing to anything. Do we have any assumed contributors? This is something that we can do if a sample is taken directly off of an individual. We can assume that their cells are present, and therefore their DNA will be present in that profile. For example, a vaginal swab, we can assume that if it came off of a female victim, that the female victim's own DNA is on that vaginal swab, along with potentially anybody else's that we may be able to detect. So we can use that to help us in interpreting these mixtures. But it is important that we have standards collected from known individuals to help with that process. We then compare what's left over or any resulting profiles we've been able to pull apart from a mixture to the profiles from those individuals, and then calculate any statistical weights to inclusions. Next. Touch trace DNA, as we talked about, very small amount of DNA starting material. Some of the things that can complicate as far as DNA analysis means that we're going to, as an end result, get very low data or low peaks. Things start to happen when they're really low. We could have what's called dropout. So some data at the locations that we're looking at maybe don't cross the threshold to be able to be seen. And so we might get some data at some locations and no data at other locations. That results in what we call a partial profile, meaning we don't have all information at all STR locations that we're looking at, but we do have some. So when we do have some data, we can still compare to that, but the strength of any match will not be as much as high because we don't have as many places to look at. We can also get complex mixtures. If you think about if you went and swabbed a hotel doorknob or something, how many people have touched that? How many people's DNA may be left behind? When we get over three people, we call those complex mixtures where it just becomes so much data, so many peaks, and so many possible people that we can't tweeze profiles apart anymore. And that can often result in conclusions in a report saying not comparable or inconclusive, meaning they couldn't use that profile to really make any meaningful comparisons. And so we have to be careful with trace or touch DNA as we do want to make sure that we're targeting areas and not taking too broad a stroke with whatever you're collecting because we want to target those areas where there really is contact being made. So for example, if somebody grabbed me here during an assault and they were grabbing specifically on this part of my sweater, I would want to make sure that I am not collecting or swabbing the entire sweater for DNA, but I really want to hone in on the area where the contact occurred. It's really important because we want to maximize the number of cells collected from the individual that you're looking for, and we want to minimize any other extraneous DNA from other people I brushed up against in the elevator today or something like that. And so trace DNA does have these additional additional complications. With DNA transfer, primary transfer is from one individual to an object, but it may be I just shook hands with somebody really sweaty in the hallway and then I come in and touch an object, I could potentially be transferring some of their DNA that went onto my hand back onto the object. And so we have to be really careful about not only how these are processed and what the results mean, but how we compare and it does just have that potential to get too complicated to say anything meaningful about these samples. Next. Other things to consider with trace, I think we talked about background DNA that might just be DNA that's just naturally on my shirt. Maybe it's my husband, my children, somebody I brushed up against, but now there's an assault and what I'm looking for is the assailant's DNA, but there's all this other DNA that's just naturally there based on daily life. Contamination can also be an issue because you are working with such amounts of DNA. You have to be really careful that we're not having that sample in contact with something else that could transfer maybe only two or three cells, but in the grand scheme of things, that's a pretty high percentage of the overall DNA that you're collecting. We do need elimination standards. As I said, we're always looking to eliminate people from a profile. That is the scientific method. It's always looking to disprove and eliminate, saying it's not them. And when we can't say it's not them because they are the same at every location, then we're forced to say, okay, include it. So it is important to have standards from consensual partners and other people that could have been on that particular object or piece of evidence because it allows us to be conclusive and it's not them. That's 100% conclusive. If somebody is excluded or eliminated, it is not them 100%. When they match and it's an inclusion, we will never be at 100%. It is always some statistical weight to that match, but it's never 100%. It's that person. So it is important to take care of those elimination standards as well. And then we do have to understand the limitations of interpreting low-level DNA profiles from trace evidence. Next. Probabilistic genotyping. I'm not going to spend a lot of time here, but this is rather new technology, and a lot of crime laboratories are moving this direction. I think most crime laboratories will eventually get probabilistic genotyping online if they don't already have it. It is a software package and a tool that uses biological modeling, statistical theory, computer algorithms, and probability to calculate a new type of statistic that hasn't been used much in the past called a likelihood ratio when comparing DNA profiles. It is an advanced approach to this statistical analysis, and it was developed in response to the fact that our testing is so sensitive now that we often get these complex mixtures that when it's just an analyst trying to review the data, we have to say too complex conclusives. This allows the computer to do a whole bunch of probabilities and working through combinations that would be simply too complex for just the individual analyst to do. The analyst does put some information into this. We still have to say, is it a mixture or single source? How many people do we think are in there? We give it different scenarios to look at as far as combinations, but then the computer does the heavy lift of running those algorithms. It is allowing us to now say conclusive results or draw conclusions from these complex mixtures that we previously could. We just brought probabilistic genotyping online in early January this year, January 3rd at our laboratory. It was something that took us years to evaluate to be able to bring online for casework. It is a heavy lift just bringing this online for the crime laboratory, but we're already seeing the benefits of having this additional tool to really help us with these complex mixtures that we're getting. For example, previous to having StarMix, that's the probabilistic genose typing system that we're using, we could say things about a single source sample, be very confident. Two-person mixtures, very confident. Three-person mixtures, we could say things about certain contributors, but maybe not the low-level part. It was hit or miss. If it was over three people, we had to go straight to inconclusive. It was just too complex to be able to say anything about a mixture of more than three people. Using this tool, we're already saying things about four-person mixtures and incredibly low-level partial four-person mixtures. It really has changed what we can say and brought a whole new level of sensitivity, not to the laboratory portion, but now to the interpretation of that data. As I said, things are changing all the time in DNA. It's getting just more and more sensitive. We're able to say more and more about less and less starting material. Next. CODIS, we touched on this a little bit, but I'll give me a little bit more information. Again, it's the Combined DNA Index System. This blends forensic science and computer technology in a way that builds a database, a searching database that can give us those hits or those associations between profiles. There are different levels of this database. It starts at what's called the LDIS, which is the Local DNA Identification System in a large state that has multiple DNA forensic laboratories. Each laboratory would have its own LDIS just for the samples and profiles coming through that laboratory. The next step up from there is what's called estus or the state level. All of the LDISs within a state will feed into that state's estus, but you will only have one laboratory within the state that is the estus that they all feed up into. Next level from there is the NDIS or the national level. This is maintained by the FBI. All of the estus level databases for profiles that qualify will move up to NDIS and therefore getting searched between states. At each level, there are certain thresholds that have to be met, eligibility requirements of the data that have to be met, but as long as it's eligible, it will move up that chain or I guess on the slide down that chain and be able to search at larger and larger areas. We are searching not only samples that all came into this laboratory, but within the state and then also nationally to try to link known offenders with these forensic profiles or another forensic case with this particular forensic case. In that way, we're linking local, state, and federal laboratories and DNA profiles to provide these investigative leads in case that needed. Next. As I pointed out before, there are two different parts to eligibility. One has to do with the sample types. We do have convicted offender, arrestees, and forensic or casework samples. Those forensic samples, in order to be eligible to be put into the CODIS database, they have to be from evidence directly linked to the case, they must be from the punitive perpetrator, and they can't be taken directly from a suspect. For example, if we have a sexual assault, let's say the victim is a female, there is a suspect and a sexual assault evidence kit is collected off of the suspect as well as the victim. That penile swab from the suspect will generate a profile that should have that individual's DNA on it. We cannot take that profile from that individual's own body and put it into CODIS. We have to find the DNA of that individual on something from the victim, so it's directly tied to the case, it is from the punitive perpetrator, and it's not taken directly from the suspect. So there are things that have to align scenario, case scenario, and evidence-wise to be eligible for CODIS. Additionally, there are the profile level determination of eligibility. We have to meet the minimum CODIS core loci requirements. As of January 1st of 2017, there are 20 CODIS core loci, and that means 20 locations from the DNA, specific locations, where STRs occur that all laboratories are testing for. Now, they can test for more than 20, but they have to be testing in those 20, and that's what we're looking to attempt to get in every profile, is at least those 20. Prior to that January 1 of 2017, there were only 13 that had to be tested for, and so that was an increase right there of the number of loci that we had to test. In order to be eligible to go up to NDIS, or the national level, the profile has to have at least eight of the original core 13 loci, and it has to provide what they call a match rarity estimate of 1 in 10 million, and that's because we want to make sure that the profile that's entered and searched will only return one true hit, and so that match rarity estimate of 1 in 10 million will change as the size of the database increases. They will have to change that match rarity estimate, which again provides a way of determining if I put this profile in, will only one true match be returned. If it's there, we only want one true match. Next. There are no names or other personal identifiers of anybody in CODIS. That includes the convicted offender and arrestee samples and detainees that may have profiles in there, so they're given a unique number in the system, but it might say something like CON123456. It doesn't have their name, or their birth date, or social security number. None of that information is stored in the CODIS database. It is simply profiles. The rest of that identifying information that's linked to that anonymized number is stored outside of the database and elsewhere, and so in that way, we're keeping that data as private as possible. Once a sample goes into the database, it stays there, unless somebody removes it, and there are times where we may remove a sample. For example, we put a profile in, assume it is from the punitive perpetrator, and we later find out that there was a consensual partner that we didn't know about at the time, and we get a standard from the consensual partner, and we look, and it matches that profile we put into CODIS, we will definitely pull that sample out of CODIS, that profile. It doesn't belong there. It's not from the punitive perpetrator, and so there are times where that can occur, but as long as it meets eligibility requirements, and it's uploaded, it stays in there indefinitely, and it is searching all the time. It is searching those convicted offender and arrestee samples, and it's also searching those other forensic samples, and I've already talked about a hit. It means a match between two or more of these things, and it's an investigative lead. Next. Validations, I'll just state really fast. In order to do anything in forensic science, it has to be validated, which is extensive testing of that thing to ensure that it's working as intended, and that the laboratory understands the scope, reliability, and limitations of that testing or that piece of instrumentation, so the type of validations can be broken into either developmental or internal, but both must be performed before crime laboratories can bring anything online, and this is the process that I just explained for our probabilistic genotyping. It took us three years, three years just to bring that online because of the extensive amount of testing that we do to ensure that we do understand the capabilities and limitations and can draw the correct conclusions. Next. These are just some of the standards and guidelines that we have to follow as a forensic laboratory. There are a lot out there, and they're changing, and OSAC is creating new ones all the time, and so we're very heavily regulated. We are held to very high standards, and that really drives what we do in the laboratory and even drives what kinds of conclusions we can draw from our data. I think that's my last slide. Thank you. Thank you, Rebecca. I'm sure all of you are trying to process all of this. I'm going to skip some of these slides and doing the case studies so that we can get to some questions and have time for that. There's just a couple things I want to point out before we go to questions, and hopefully this will be a teaser, so you'll make sure that date will be sent, I think, right away. That will be in mid-June, the next PowerPoint on DNA. At that next presentation, we're going to be talking about specifically the history of DNA evidence collection in sexual assault cases. Huge shout out to the victim advocate, Marty Goddard, who really was the one that came up with the idea of sexual assault kits. We will talk about then swab technique, types of swabs, wetting solutions, and especially the importance of communicating all of this with your crime lab. We will spend quite a bit of time talking about the length of time of evidence deposition, the time between the assault and the exam. I just want to refer everyone to our best practices. The most recent is the National Best Practices for Sexual Assault Kits. I hope you're all familiar with that, a multidisciplinary approach. There's an entire chapter related to forensic examiners. This is some of this information. This is all in our resources, too, that we will be going over additionally at the next presentation. I do want to highlight, Rebecca went through how careful they are in the labs to avoid any contamination of this evidence. I know there has been some conflicting responses about pre-COVID, about the importance of wearing masks when we collect DNA evidence, when we are collecting those swabs from our patients. I hope as she went over the precautions that they take in the labs, that you realize the importance that we also take. The importance, of course, wearing gloves, but also wearing a mask, limiting the number of people in the room, not talking over the moist or wet swabs while they are drying, even with a mask on. If there's any males in the room, especially make sure that they wear a mask. Really important that we avoid cross-contamination. Hopefully, that gave you a good viewpoint over after we pass off this box, this kit, what happens to it in your crime lab. I hope this also piqued your interest to learn more about what's happening in my crime lab. Rebecca referred to the fact that every crime lab will have different protocols. I think it's really important that you understand the process for your crime lab. These are the case studies that we will be going over at the next presentation, where you hopefully will really see in action some of the processes that Rebecca talked about as far as outcomes. We will start from the scenario of the sexual assault to what was collected in the exam and then the DNA analysis findings. I always like to close with how I end my exams with my patients. I tell them that I love flowers. My favorite flower is the crocus because the crocus always blooms no matter how long the winter is or how cold it is. That's my vision for my patients, that they're going to take this really hard thing and still find a way to bloom. Our university did a YouTube video on this message that's about three or four minutes long, if any of you are interested. This is actually a card that I give to all of my patients and now our forensic nursing team also gives that. We will go to questions. There are references as well. Gail, do you want me to read the questions or are you going to read those out? Julie, however you prefer. How do you prefer? I will just go through and Rebecca, if you want to unmute because some of these are for you and it looks like she's typing an answer. You copy DNA for comparison to other samples. I don't know if you want to unmute and just share. Sure. I've already answered two questions typing as well because I wasn't sure if we were able to get to them and I wanted people to have answers. Yes, what we do is we make copies of very specific areas on the DNA that we're targeting. As we talked about, CODIS now asks us to test at least 20 locations. We are making exact copies of those 20 locations where those STRs occur and it is copying down to the sequence level. It is using the same process that our own cells use to replicate our DNA as we build a new cell and replace our current cells. It's using that exact same process to make copies of that area so that we have enough to detect on the instrument. Yes, we are. Awesome. The next question and Rebecca talked about this. How many samples from the kit do you routinely test and how do you pick the swabs? She discussed that a bit about reading the history. Again, that communication between the forensic examiners and forensic scientists is really important. Many crime labs do not test every single swap that comes in a kit. When you read the National Best Practices, it talks about in there the importance of trying to concentrate as much DNA as possible on the collection of two swabs. If the patient reported breast contact by mouth, you can do two swabs and do breast swabs and collect two swabs. You don't need to do one swab, two swabs, white breast, two swabs, left breast, right nipple, left nipple. It's better for a body area to concentrate that DNA. Anything else you want to share on that, Rebecca? No, I agree 100% and I thank you for pointing that out. We have had samples before where somebody was collecting right labia majora, left labia majora, right labia minora. When that happens, you're still collecting everything, but for the crime laboratory, when they're submitted as separate individual samples like that, we have to process them as separate individual samples. What could have been one set of two swabs over that entire area, maximizing the amount of DNA, as Julie just mentioned, and taking that forward, we now have four different swabs and each one has 25% of what you otherwise would have had. Maybe we don't develop a profile on any of them because there isn't enough on any one swab to get us that DNA profile. That is a really, really important thing to point out. Thank you for saying that. I don't know if we're going to have time to get to all of these questions. I'm trying to see maybe what's going to... There is a question on non-human DNA. I'll just point out our testing, STR testing is specific to human DNA. When it comes to animal DNA, you really would need a whole different system to process animal DNA. However, some laboratories do have the ability in serology to test for different proteins and identify the proteins in a sample to an animal. It really is going to depend on what your crime laboratory has available to them and what type of testing they perform, but the majority of the DNA testing in crime laboratories will be human specific. Thank you. Very interesting. We are at time, so I'm going to stop sharing that PowerPoint. I hope we have a lot more to share. I hope you can join us and it will be recorded at the next presentation. With that, I will turn it back over to you, Gail. Thanks, Julie. Again, today's webinar is being supported through IFN's technical assistance grant. Through this grant, IFN hosts the Safe TA website. That website hosts various educational opportunities, resources, and national guiding documents. You can contact IFN with any request for technical assistance by directly calling the TA line at 1-877-879-7278, or by submitting a request form by clicking the request TA button on the website. Thank you, Julie and Rebecca, so much for this webinar. It was very interesting. Remember, join Julie and Rebecca in mid-June for part two of this webinar. Thanks to everyone for joining us today. Remember to complete the post-webinar evaluation. The link has been dropped in the chat, and you should also receive an email shortly after this webinar concludes. Thanks, everyone, for attending. Thanks, Julie and Rebecca, for presenting, and have a good day. We hope to see you guys in the future for other webinars.

DNA analysis

sexual assault cases

forensic nurses

forensic scientists

trauma-informed services

forensic evidence collection

trace DNA

STR DNA

Y-STR DNA

CODIS

perpetrator identification

probabilistic genotyping