Friday, January 11, 2019

is Gedmatch o.k.?



Dr. D got the following query earlier this week.

One of our Roots group members asked me today if GedMatch is an o.k. place to transfer his data.  He had gotten an email suggesting to him that he transfer, and he didn't know if it is safe.  I think mine has been transferred there, but I never get any emails from them telling me if I have matches.

I quickly responded that the simple answer was “Yes.” However, I realized that a more nuanced answer was required:
There is no universal answer that is “RIGHT” for all of us in all situations for all time.
 
Although GEDmatch has been well known to serious genetic genealogists for several years, the site exploded into the consciousness of a wide media audience following Barbara Rae-Venter‘s skillful use of this database. She was able to significantly “shrink the haystack” and help police focus on the needle who had eluded them for decades. In April, 2018, her efforts led to the arrest of Joseph James DeAngelo, Jr. He is alleged to be the “Golden State Killer” who is suspected of at least 12 murders, 45 rapes and more than 120 residential burglaries. He has yet to come to trial.



In the months that have followed, Rae-Venter has had similar successes with other cold cases and CeCe Moore has solved more than a dozen. GEDmatch has been instrumental in almost resolving all these cases that long had been considered unsolvable.



Why GEDmatch? It is not the largest of the databases of genomic information created for genealogists. Several of the DNA testing companies claim to have records of more individuals. However, it is different in several fundamental ways:

1.   Most of us who use GEDmatch were initially drawn there because we could match our DNA with known or unknown cousins who had tested at commercial labs other than the ones at which we had tested.

2.   GEDmatch is not a commercial for-profit enterprise. It does not advertise its services. Actually as its logo suggests, it might be more accurate to say GEDmatch provides tools for us to use ourselves rather than that it provides services to us.

3.   GEDmatch does not have a paid staff to provide all the services some other sites offer in terms of individualized customer service. For example it does not send notices when new matches show up. Users of the service must initiate searches to keep abreast of new matches. This makes the site useful to the genetic genealogists who take the initiative to use the myriad of tools provided.

4.   For most of its existence GEDmatch has been operated entirely by two “retired” men who are avid genealogists. Curtis Rogers and John Olson like to use their skills to help others unlock mysteries about their families.

5.   They originally charged no fees but eventually added small monthly fees for those who wanted to use advanced tools. This allowed Rogers and Olson to pay for the server time these features required.

6.   The basic level of services at GEDmatch is provided free.

7.   Although using GEDmatch does not require high level technology skills, an absolute novice may have difficulty gaining the traction needed to make the best use of features.

8.   GEDmatch does no testing on raw DNA samples. Instead it accepts testing data from commercial testing companies such as 23andMe, Ancestry, FTDNA, MyHeritage, and Living DNA.





3 reasons individuals test our DNA:

  1.  To discover information that may impact our health and/or that of our offspring.
  2.  To discover information about our ethnic origins. Market research has shown that this is the reason most millennials test. That is why television ads focus on what is probably the least settled of what our DNA can tell us. Although these first two processes may indirectly provide information about close family members, we do not need to directly compare our results with those of others to get useful information if these are our objectives.
  3. To discover information about connections with others. This is why adoptees and others of unknown parentage test. It is also the primary reason most genetic genealogists test. To be successful this activity must be a CONTACT sport. That is the objective!  

It is this latter group that GEDmatch is best suited to assist.



A tool for helping solve cold cases:


What has changed with the solutions of the cold cases? Many law enforcement officers have become aware of the power of genetic genealogy. Some of them have attended a seminar conducted by Rae-Venter on making familial matches. This is the same process through which adoptees have been searching for biological connections.



A recent article in Science reported that statistical simulations indicate more than half of Americans of European descent can probably be identified given the current 1.2 million names in this database.

Using genomic data of 1.28 million individuals tested with consumer genomics, we investigated the power of this technique. We project that about 60% of the searches for individuals of European descent will result in a third-cousin or closer match, which theoretically allows their identification using demographic identifiers.
Given the current growth rate of GEDmatch, it is projected 90% of those with European descent may be subject to identification within a couple of year.

Police have long had access to a hodgepodge of CODIS related data mostly derived from DNA testing of convicted or accused violent felons. Like our current prison populations, these databases are dis-proportionally constituted of minorities and men of lower socioeconomic groups. The current rash of cold case arrests have been successful because investigators were able to tap a very different demographic.


Community security vs. individual privacy 

Two fundamental rights are now in conflict. At the moment it appears that most members of the public are willing to tip this in favor of community security if we are talking about investigating violent crimes. In a US survey 91% were in favor of allowing police to search genealogical websites that match DNA to relatives in order to identify perpetrators of violent crimes (for example, rape, murder, arson, or kidnapping). Among respondents 12% had ordered a DNA test and 37% had researched family online. 

A parallel international survey of genealogists (41% from the US) reported by Maurice Gleeson asked, "Are you reasonably comfortable with law enforcement agencies using your DNA data on Gedmatch to help identify serial rapists and serial killers?" 85.1% responded "yes" and 8.6% said "no". When the undecided are filtered out the results of the two surveys are very similar.


Should you feel comfortable uploading your data to GEDmatch? Reasonable people can disagree. However, more than 90% seem to form a fairly solid consensus in favor.

What do you think?