Cece thank you so much for joining us you have solved about 40 cases so far is that correct or generated leads that.
Were up to 58 successful identifications i believe three of those were an identified victims and the rest were an identified suspects so two different types of cases So first can you please tell us about that database you're using to find the distant relatives of suspects for these cases?
Are you directly accessing services like Ancestry, or is it something different?
We're not using the largest consumer DNA databases, so we're not accessing Ancestry DNA, 23 and Me, MyHeritage.
Instead we're using a public website called GEDmatch.
And in order for someone's DNA to be in that website they have to have actually gone through the steps to upload it there.
So nobody's DNA is just gonna show up there unexpectedly.
If you have put your DNA in that database, you would know it because it's actually fairly intensive to get the raw data file from the consumer DNA testing company and upload it into the database.
So if you still want to participate in consumer genetics without having your DNA used for law enforcement purposes, you can certainly do that.
Okay, so can you tell us a little bit about that database and how it works?>> Sure.
Jed match is a database that was started by two citizen scientists about in about 2010.
And that's Curtis Rogers and John Olsen.
It was started as a place where people could upload their DNA from different databases and cross compare So if you tested at Ancestry DNA and I tested at 23 & Me and we didn't want to buy another test, we could just upload both of our data files there and compare to see if we shared any DNA.
It was also kind of a sandbox where we could try out new tools, new features- People that develop these tools could try them out there.
Because it wasn't a commercial database, there was more freedom to try different things there.
So, can you walk us through what happens when you upload information about a suspect in that database?
What does that help generate for you?
So there are about 1 million people participating in the GEDmatch database.
Unknown DNA from the crime scene is analyzed in such a way that we're looking at hundreds of thousands of genetic markers, so those As, Ts, Cs, and Gs.
And when it's uploaded to Jed match, its compared to the hundreds of thousands of genetic markers for each of the million people that are participating there.
What we're looking for are long stretches of identical sex.
Segments of DNA.
So we're not looking for single marker matches like you would in the traditional forensic profiles.
Instead, we're looking for these long segments where thousands of genetic markers in a row are identical, because that tells us that these two people share a recent common ancestor and time.
There's no reason you would have that shared DNA otherwise.
And so we can look at the family trees of the people sharing DNA with the unknown suspect and use that to reverse engineer his own family tree.
And so that's how we're able to reach these potential identifications.
Tell us what has happened now that folks are not automatically opted into law enforcement investigations on dead man So for the past year, the terms of service at Jed match have allowed law enforcement files to be compared to everyone in the database.
At least everyone that had their DNA public.
And recently in May, they made the decision to opt the entire database out for law enforcement matching.
And people have to physically go there and change the setting to [INAUDIBLE].
Unfortunately a lot of people don't visit the site again.
So they haven't necessarily even become aware of this change.
But what it means is we're only using about 5% of the database now for law enforcement matching.
That has an extremely negative impact on our ability to identify these unknown suspects in violent crimes And also the victims in some cases.>> So after you find the names of distant relatives on Jed match, what do you do next?>> So when that unknown suspect or victims DNA is uploaded to Jed match and it's compared to everyone else in the database, we get a list of people that share significant amounts of DNA.
Now at the top of the list are the people who share the most DNA so they would have the closest common ancestor and time But there's up to 2,000 matches listed, but the vast majority of those are very, very distant.
So we're looking at maybe the top dozen or 20, sometimes even 50 of the matches.
We're building their family trees and we're looking for commonalities.
We're looking for common geography, surnames and, hopefully, common ancestors in their trees.
If we can identify common ancestors in the family trees of the people sharing DNA with the suspect, then we know that those common ancestors also belong in the family tree of the suspect.
And then what we have to do is called, ascendancy research.
Once we've identified these key common ancestors.
We do what's called reverse genealogy or decendency research, and we want to then come forward in time instead of backward in time.
Instead of looking for long dead ancestors, we're now looking for living people that are descendants of these ancestors and who lived in the right place at the right time, perhaps are the right gender, right age or any other circumstances.
that could make them potential persons of interest to the case.
So what do police do after you give them a list of potential suspects when you've done this research?
So every case is different as far as how strong the data is that returns.
Up at that top of the list, we're hoping to see maybe a second cousin or closer.
We don't always get that.
So in some cases, we're able to point them toward just one person and say this is the one person we think is carrying the correct ancestral mix.
Sometimes it's brothers or cousins.
But with some cases, there just isn't enough data to do that.
So we might only be able to narrow it down to great grandparents say or great, great grandparents.
and we can say we know that he is a descendant of this ancestral couple, he's from this area and this population group.
And I don't mean like African American versus Latino versus European.
I mean much more specific things, like New Mexican roots or- Say Mennonite roots in Indiana, that type of thing.
And we know that they can then rule out all of these other possible persons of interest who don't fit into that.
And so it's not always a situation where we can give them the name or the potential name of the person.
But when we can do that Then what they have to do is just take that as a tip, or a lead generator and build their traditional case against that person, if they're able to.
So, it doesn't replace the traditional police work at all.
They still have to go out there Investigate that person see if they can find any ties to that crime and then collect usually abandoned DNA to compare it to their traditional forensic genetic profile.
Thank you so much CC.
If viewers want to know more, they can go to dnadetectives.com.
Thanks for having me.