DNA Identification of Missing and Unidentified US Soldiers

The Armed Forces DNA Identification Laboratory (AFDIL) was established in 1991 as a division of the Armed Forces Medical Examiner System as the only Department of Defense forensic DNA testing laboratory for the identification of members of the US military who lost their lives during conflict.


In this interview, Laura interviews Suni Edson, who works within the Past Accounting Group at AFDIL. She shares a project that she has been working on since 2014 to identify those who perished at the Cabanatuan Prison Camp located in the Philippines during WWII. While the prisoners where allowed to keep records of those who had passed at the camp, the remains were subsequently disinterred and moved to a cemetery in Manilla, where they were unintentionally co-mingled, fixed with a formalin powder, and subjected to environmental degradation.


Suni describes the careful work being undertaken to identify the 3,000+ remains located in this cemetery as well as challenges that the team is facing, and new research being done to overcome them to return the remains to family members for a proper burial.




Laura: Thank you for joining us for our annual video series from the International Symposium on Human Identification. We’re in our 33rd year this year and we’re very honored to have Suni Edson with us today. Suni, hi, how are you?


Suni: I’m fine, how are you?


Laura: I’m doing very well. Can you tell us a little bit about your work? I would think it’s very interesting to work with the armed forces division.


Suni: Yeah, I work for the Armed Forces DNA Identification Laboratory. We’re part of the Armed Forces Medical Examiner System and so what we do, is my group, which is the past accounting group is tasked with the identification of missing soldiers from past military conflicts. So, we do DNA testing and we’re mission partners with the Defense POW Accounting Agency. So, they’re the anthropologists and the archaeologists, and we’re the lab people doing DNA work.


Laura: Wow, that has to be fascinating. I think you’re speaking during this conference about WWII and the identification of the missing in action.


Suni: Yes, I’m speaking on Thursday about a very particular incident which is the Cabanatuan Prison Camp, which is located in the Philippines and is an estimated 2,736 individuals in a single prison camp. So, for WWII, we currently have over 88,000 individuals are still listed as missing and unidentified. So, what we focus on is we do WWII and we also work Korean War losses. That is fewer. We’re down to about 8,000 missing and unidentified. And we also work on Vietnam ear losses. So, we and DPAA are tasked with anyone who is declared missing and unidentified from any kind of US military conflict.


Laura: Wow, those numbers are staggering. How does the process work?


Suni: Well, a lot of times now, the DPAA anthropologists go out and they’ll do recoveries from crash sites, so anytime they gather all kinds of intelligence about where people might have gone missing, so crash sites, airplane crashes, ships that have sunk, any kind of area where they know someone might have gone missing. But, they’re also big into looking at cemeteries where unknowns might have been buried. So, for WWII, they’re going to local cemeteries where perhaps local individuals have said, “we buried the remains of a plane crash here.” Or battlefield losses, where they know individuals might have been buried. So, they’ll go out and disinter them, and do all the anthropological and archaeological work on it and then provide samples to us for DNA testing.

In Vietnam and Korea, it’s a similar process, but in Korea we have partner agencies, and they work with the South Korean identification efforts. So, they have their own anthropology lab and they’re also a military branch and help our anthropologists do recoveries. In Vietnam, Cambodia, and Laos, they also have partner agencies that they work with to do recoveries. So, it’s a worldwide mission. They’re out all the time doing recoveries everywhere.

So, Cabanatuan Prison Camp, on which I’m speaking about on Thursday, is a disinterment project that they did in the Manila American Cemetery. So the remains were recovered from the prison camp in the 1950s and were transferred to that cemetery and buried as unknowns there. So, since they’re able to go out and hopefully we’re able to identify people from that now. So, that’s one of the projects that we’re working on now. It will be the largest single project that we’ve worked on.


Laura: That is incredible. It does sound like an enormous project, so that does make sense. What does a day in the life look like for you given that?


Suni: For me, I unfortunately don’t get to do a lot of bench work anymore, so I do a lot of case review, technical work, going through all of the reports that people have generated and tabulating the data. So, this is a project that I work on. It’s my management project, so as we get DNA results in, I organize them, see if they’re shared between any of the DNA samples that we’ve tested, see if they match anyone that we have in our family reference database, and provide that information back to the leading anthropologist back in Hawaii.


Laura: Wow, that’s amazing. It’s almost hard for me to wrap my head around. You must have so many cases to review. How did this project come about originally?


Suni: For this project itself, at the time of the loss, so I’m going to tell a little bit about the history of it. At the time of the loss, while the prisoners were in the prison camp, they were afforded the opportunity to take records of who was buried in each location. So, there are over 1,100 graves associated with this particular incident, but in the three years the prison camp was open, it was almost 3,000 individuals who died. The prisoners were allowed to keep records and keep a cemetery for themselves. So what they did was they placed their identification within their person, so either put it on their body, or in instances where they had their identification media removed, they wrote notes about the person. So, they had very detailed records. So, when American Graves Registry came in when the camp was liberated, they were able to get those records and map the cemetery. So, technically, everyone there is identifiable. But, they disinterred them and moved them to Manilla and buried them as unknowns. At the time, with the anthropology and we’re still in the middle of a way in 1945 and still dealing with the war in Europe and the war in Asia. There were so many other things going on. We were dealing with the fall out of Pearl Harbor still and the individuals who were lost there, so the families came to us in the early 2000’s and said, “We think we know who should be in these graves.” So, they’re technically identifiable, and according to our mandate and the mandate for DPAA, we needed to go out and see if we could do that.

So, this started as a simple project. We just exhumed one grave and tried to identify the 14 individuals who were supposed to be in that particular grave. And given that we had a decent amount of success with that one, we decided that this needed to go on and be a complete project and we continued to exhume the rest of the graves associated and try to identify everybody who was present and not just one. Because if you say that we’re able to do one, then why didn’t you the rest of them? And, we owe it to the families to be able to provide them that kind of information.


Laura: That is a wonderful history to help frame it and working with the families and also was it usual for prisoners to keep a record like that were it started the work to move the unknowns?


Suni: Sometimes. It depends on the camp. And this was just very particular in that once it started, prisoners left, because they were being transported for work details, but the Philippines are in the middle of the ocean, so they didn’t add to this very much. And, you had people there who were there for an extended period of time, and therefore were able to work with the captors and make it so they could keep records and gain their trust and understanding so they were able to make record of what was going on.


Laura: That is very interesting. That’s something I didn’t know or hadn’t heard of. So the work you’re doing, obviously there’s an incredible mission to do this for the families, but it can’t be easy when you’re disinterring. There must be some kind of co-mingled samples and challenges that you’re facing. What does that look like?


Suni: Well it’s been a big challenge for us, because when they were buried together, they were buried together in a common grave, so the individuals weren’t buried separately. They were buried together in a common grave for the day. So, everybody that passed within that 24 hours were buried in a single grave together. So when American Graves Registry went in, it’s very hard to keep people separate. You’re faced with a very small group of people trying to disinter almost 3,000 people and try to transport them to another location. So, there is extensive co-mingling.

One of things we do in large, mass-scale fatality events like this, and especially for WWII, is individuals were bundled or bundled together and then placed in a coffin. So, they believed it to be a single person and so they weren’t always right, and it’s through no fault of their own. They were doing the best that they could in very hard circumstances. So, that’s our job now to try to untangle that and reassociate the remains together and try to return an intact person to their family.

So there’s a lot of co-mingling in those instances and sometimes it’s small elements, such as finger bones, and mostly not large elements, because the anthropologists are able to associate the larger intact fragments together. They use all kinds of techniques such as measurements, examination, whether or not the weights are balanced between themselves. I always like to say that DNA solves everything, but there’s a lot of other parts that go into it. The anthropologists use a whole series of different measurements to associate remains together and then give us the opportunity to say, “yes it matches this family member.” So, there’s a lot of different moving pieces that go together.


Laura: What an amazing chain of highly skilled professionals to do this piece by piece to arrive at an answer.


Suni: It’s a lot of moving parts.

Laura: Absolutely, absolutely. Where are you at in the process. What will you be sharing in your presentation?


Suni: Well, I’m going to start by talking about it was unexpected for us, because we kind of started out with the whole process of this is something that we should be able to do. We were using DNA extraction techniques where it didn’t matter which skeletal element we sampled from. Almost everything worked. It was about a 95% success rate. So, when we come into this, we go, we shouldn’t have a problem. And then it turns out there was so much more that we didn’t anticipate that became a little bit of a challenge. For instance, when you put a cemetery in the middle of a city, there’s a lot of concrete asphalt, so water does not drain appropriately, and Manilla has over 80 inches of rain a year. And I say that, and people say that doesn’t seem like that much. And then you go, Seattle, which everybody says is rainy, gets 37 inches of rain a year. And so, the water table was a huge challenge for us.

The lead anthropologist, Mary Legacy, and I are trying to figure out how this has either helped or hindered our process. But, there’s so much water there that you literally cannot lift the coffins without having them drained of water first.

But, one of the interesting things that we found was the remains were treated with formalin, what they call a hardening compound, and it’s to preserve the remains during transportation, and we didn’t expect this to be an issue, because we didn’t know this had happened. Typically this is only done when remains were being transported oversees, so we can only imagine that American Graves Registry anticipated they were going to send the remains overseas. They didn’t know they were just going to move them 100 miles and bury them there permanently. So, they were treated with formalin powder, and what formalin does is binds to proteins in DNA and prohibits them from being unzipped. So, you get a lot of DNA from the remains, but you can’t do anything with it. So, PCR when PCR treats DNA is it unzips it. And what formalin does is it binds into the protein and kind of you know when you get your zipper stuck and it won’t move? So, that’s essentially what formalin does. It prohibits it from unzipping.


Laura: That is a great analogy for viewers who are watching who aren’t familiar with that, but wow. So, now you have that where you can’t unzip some pieces of the DNA, you have degradation from water, you have transport. How do you overcome these challenges?


Suni: Very slowly. But, I think that we have the real opportunity at our laboratory to be able to take the time and make things work, because we don’t have the opportunity to say no, because our goal is to provide answers to the families and to return these service members home. We don’t have the option of saying no or saying, “Well it didn’t work.” We are really fortunate to have our emerging technologies section and they take the time to say, “well this might work. This might be a solution.” And I was really lucky to have two of our analysts who determined a new method for extractions to try to find other ways to work around the problems we were seeing. The beginning of the project was 2014 and we were just doing basic mitochondrial analysis, but then we started with a process that I’m sure other people have talked about, which is next generation sequencing, or massively parallel sequencing, that allows us to look at very tiny pieces. So, like I was saying with the DNA being bound and you can’t unzip it? Well there are pieces that break of and there are pieces that are in between called free DNA, so we have a process in our lab called a capture based assay and we literally use different materials to pluck out these pieces of free DNA and re-assemble them into a whole and that’s part of how we’ve gotten around the issues. That way, we can generate an entire mitochondrial genome with things we didn’t previously think would work.


Laura: That is incredible. I mean that sounds almost impossible. It’s amazing what you’re able to do by taking those pieces and reassembling them. The technology as come so far and the work you’re doing for this to come together. That’s amazing that you’re sharing this year. That kind of leads to the next question. What advice would you give to other people whose work isn’t exactly like yours, but who are facing some of the same challenges with their work?


Suni: Take the time to really try to figure out what happened. One of the biggest things I like to say to people is talk to your anthropologists. As a DNA person, we often go, we’ll solve it. Don’t go talk to those people who dig in the ground. But, we do need to talk to everybody. It’s a collaborative effort, so we should build relationships with all the other labs who are building your picture. DNA is just a piece of the puzzle, so for human identification take the time to really learn about the incident. So, all the time we say that DNA should be done in the blind so you shouldn’t be biased, but I think when you’re working in a situation like this where you have a mass fatality event, you have to talk to people. You have to talk to them and say, “this isn’t working. Do you know what happened?” We didn’t know they were formalin-fixed. This happened to be a historian who stumbled across the records that said this is what happened and we didn’t know they were full of water until we talked to the anthropologist and said, “This is what’s going on. Is there anything about this that we should know?” And she says, “Well the coffins are full of water. Would that have been a problem?” Yeah, that would have changed our approach. So, talk to people and really find out, because that will allow you to adjust your approach and give you more time to be successful in what you’re trying to do instead of just “I tested it. It didn’t work. I’m going to move on.” No, figure out why. We’re all scientists. We should take a moment to figure out what happened.


Laura: That is excellent advice and I feel like a theme from many of the interviews this year is that it’s about working with the anthropologists and the historians and knowing the story before it gets to the point where you’re testing DNA. We’re seeing that over and over again and I think for people who are facing cases, that is valuable advice and that’s definitely why we have you here presenting. It’s very clear. What is next for you if you can share? Back to it?


Suni: Back to it. I will go back on Friday and go back to case review and continuing to assess the data that has come in over the last month. Once a month I sit down and take all the data that we’ve worked on in a month and analyze it into the organization and try to figure out if we have new people, do we have more pieces of people that we’ve already located or have different files, and try to get organized on that. Because we are doing some limited short tandem repeat or STR testing on these remains as well. We’re really hopeful in the next year or so to have SNP testing online with this, because that should be able to… One of things with WWII is you don’t have references available, so your references aren’t siblings or parents anymore, they’re nieces, nephews, cousins, so we’re really hopeful to bring on SNP testing, because that will allow us to use anybody in the family lineage for a family reference.


Laura: That’s really amazing when family kinship can play a role and you have the ability to trace back without using a direct descendant.


Suni: Yeah, it’s really incredible.


Laura: Have you attended ISHI before?


Suni: I have. I have and I love it and it’s always a meeting I really enjoy attending. It allows us to do all DNA all the time, but to also do a lot of networking and meet other people who can help provide guidance on the things that you’re working on.


Laura: It’s really a wonderful group and I am so honored to be able to interview you this year. Thank you for taking the time out to talk with us.