- When you upload your information into GEDmatch
do you realize that you're uploading
your sisters, your parents, your potential grandchildren's
genetic information into this system.
- DNA registries are the newest tool for investigators.
- The match investigators were looking for
had to wait for a more modern database to emerge.
- Authorities saying they found a match
for DNA collected at the crime scene on a genealogy website.
- Thanks to a genetic genealogy site called GEDmatch,
detectives were able to match the suspect's DNA.
In reality, DNA is going to be everywhere
It's going to be on your cellphone,
it's going to be on the objects
that you touch on a regular basis.
You pick up a knife, you pick up scissors,
you touch a door handle.
Your DNA is going to get transferred
onto every surface that you make contact with.
But a DNA profile for forensics is only valuable
when you can compare it to something else.
From a DNA sample there are so many different
avenues that you can take.
You can do traditional DNA typing.
in order to make inclusions
and exclusions about the evidence.
But then you can also explore phenotyping,
which is looking at the hair color, the eye color,
the skin pigmentation of an individual.
And ancestry informative markers,
which are allowing you to gain information
about where a person might've come from.
So if an individual has a particular allele or
at one particular location in the DNA,
it could mean that they likely originate
from one particular part of the world.
Because that variation, or that polymorphism,
is only seen in that part of the world.
In the context of cold cases, missing persons,
and unidentified human remains,
phenotyping and ancestry become extremely powerful.
There was a case on the west coast of Canada
involving a young girl who was murdered, Marrisa Shen.
And they didn't really have any investigative leads
or information about the suspect
from the DNA profiles that they generated.
So they then took that DNA, and performed
phenotyping and ancestry testing in order to
gain inferences about the suspect.
So they were then able to build a composite profile
about where that suspect likely came from,
and what that suspect potentially could've looked like,
in order to take the investigation in a new direction.
GEDmatch is a free public database.
And how GEDmatch works is individuals who
participate in programs like 23andMe,
Ancestry.com, MyHeritage, etc.,
download their individual profiles from
the paid programs that they participated in.
And then upload independently their profiles into GEDmatch.
The more you are related to somebody,
the more similar your DNA will be.
And so GEDmatch takes all of that genetic data
that you've put into the system
and then starts matching it and giving you a number
as to how much of your chromosomal DNA
matches somebody else.
So how investigators are able to really take advantage
of this new genetic genealogy era,
they essentially just mimic how these companies
have designed their DNA kits.
And so they take the crime scene evidence,
and they run it through this new DNA kit
that gives a DNA profile, or a genetic output,
that is very similar to these big companies.
And from there they can upload it
into the public database in order to see
if there are any potential relatives
or any potential matches.
For example, the Golden State Killer,
they uploaded the crime scene samples of the suspect,
and they searched GEDmatch.
And they found that there was an individual
in the database who shared a large amount
of genetic information.
And then they then were able to narrow down
their suspect pool, looking at who that individual was.
And they did that using genealogy records,
because all of this stems from the genealogy,
and looking at marriage records and familial trees.
When they were able to get an inference
as to who the suspect may be,
they then followed him and collected evidence
that he freely discarded.
And then they compared that DNA evidence
that they collected to the crime scene samples
that they had in the lab.
People are choosing to put their genetic data
out there for comparisons to be made.
The investigators are utilizing
kind of like the Facebook of genetic databases.
People are freely providing this genetic information
and it's just becoming another investigative tool.
That public database will only be as useful
as we allow it to be because we are the ones
contributing the information.
One really interesting thing about
the Golden State Killer case,
after the Golden State Killer was apprehended
using this freely available public database,
there was actually an increase in the amount of profiles
uploaded into the database.
And I think this speaks to people's innate desire
to help, or to want to contribute to
a better society, to the greater good.