Saturday, August 13, 2022

Is STR (CODIS) Testing Adequate for Birth Parent Searching?

Post script 10/12/22

This week a scandal broke in the Netherlands regarding a popular TV show there called "Spoorloos" (Without a Trace). The show, which helps adoptees from all over the world locate birth family, apparently failed to verify potential birth families through DNA testing. The result is that a number of adoptees who thought they had found their birth families had in fact been misled. Of the four birth families tested so far, two have been shown to be unrelated to the respective adoptee.

These cases involve birth families from Colombia, but China has seen similar cases. In the Spoorloos cases, a simple DNA test would have prevented a lot of pain. This morning the Belgium story gained some additional publicity with a TV news interview of Noemi Plateau, the subject of the article below. Her story is different from the "Spoorloos" scandal in that in her case DNA was used, but with an inappropriate DNA test. The problem was compounded by a lack of understanding by several members of the testing chain as to the implications of her test (Video from the documentary is imbedded in the article). But the result was the same: An adoptee was misled to believe their birth family had been located, when they in fact had not.


In June 2021, I was contacted by documentary film-maker Lidewij Nuitten in Belgium about being part of a series involving roots searching (Entitled "We Are Family", the trailer and series can be seen here). The series would feature different people involved in searching for lost family, including two Chinese adoptees. The adoptees and the film maker asked if I would help them in plotting a path forward for their search, and I readily agreed. 

The series was broadcast in June 2022. Composed of six episodes of about 30 minutes each, the series documents the efforts of the film-maker as she searches for her family's historical roots, combined with her following the search of the two adoptees. It is a very heart-felt journey for all involved, and definitely worth watching if you live in Belgium (or have a VPN outside of Belgium). 

For the purposes of this blog article, I will focus on the two Chinese adoptees profiled. They enter the film about a third of the way through episode 1 (1-11:54 -- future references to the series will include the episode number, and time mark). Episode one introduces them, and the remaining five episodes alternates back and forth between the two story lines. For brevity I will simply say that the first step taken was to test themselves with 23andMe, Ancestry, and MyTapRoot (MTR) (1 - 32:24).

In episode 2 (2-12:11) I participated in a Zoom call where we discussed the finding information of both adoptees, as well as some ideas on how they could conduct a search. 

In episode 3 (3-1:20) the adoptees get their first DNA results from 23andMe and GedMatch. Like most other adoptees from China, their closest relatives were third-fourth cousins. They film an innovative TikTok video, and start a media campaign inside China.

It is in episode 5 that the events occur that will be the focus of this article. One of the adoptees gets a message from Roots of Love (5-23:12) (One can watch these segments from the documentary in this article linked above). 

After introducing themselves, the representatives of Roots of Love tell the adoptee that a recent search project in  Chongqing had netted 20 birth family samples, all submitted to MTR's STR/CODIS data base. "This week, we heard some news that there was a random surprise match with one of our other birth parents in China. . . . And we found out that it was you. We have positively tested your birth father." As the adoptee begins to weep, they went on. "But the DNA came back as a complete match to you," CRL continued. According to Roots of Love, the DNA matched on all 21 loci. 

Roots of Love emphatically claimed to the adoptee that they had located the birth father of the adoptee. "There's absolutely no doubt. It was a perfect match."

The birth father, however, had doubts. As far as he knew, he had no children from 1996, so it seemed impossible in his mind. So he requested a new test, a more detailed STR/CODIS test, that looked at 30 loci instead of the 21 that MTR tested for. The adoptee was called again, not by Roots of Love, but by MyTapRoot. "The second DNA results are in," she tells the film-maker, "because something about the results wasn't right or something." 

"I don't know how I feel," the adoptee starts the conversation with MTR, "because it is a bit weird. I am a bit confused. Is it possible to, like, quickly explain what happened with the second test?" The MTR representative begins, "With your initial test, your first test, we measured 21 loci, and that is what we always measure for our test, 21. And if it's 21 out of 21 match, we notify people that is is a match."

The adoptee was then told by MTR that the test that the birth father requested seemed to largely confirm a relationship to the adoptee, according to MTR's representatives, although it failed on two loci. "When we received that report and re-matched it, out of the thirty, two were not matched." That failure ruled out he being the birth father, but they speculated that he was, nevertheless, a very close relative. "Because of the amount of similarity in your loci, it's so similar, to the point that it cannot possibly be an uncle or a brother. It's closer than that," the adoptee was told. This understandably created a deep emotional response from the adoptee. "Has anyone else got a confirmation and then it was not a confirmation?" she asks. No, was the reply, "you are the unlucky first, I guess."

And that is where the story essentially ends. No resolution. 

Did the adoptee really find her birth father? According to Roots of Love, she did. It was a "perfect match", according to their (MTR's) CODIS test. Even if it wasn't a birth parent according to MTR after the second test, he was a very, very near relative. But one is left at the end of the documentary with no clear answer: How were these two people related?

I met the adoptee while in Holland last May, so I reached out to her to see if she had learned any new information in the intervening three months. I asked if a third test had ever been done, as was alluded to by MTR. "Yes," she replied. "Tell me that at least it was an autosomal test," I replied. It was. Since she had her DNA in GedMatch already, the birth father was tested with 23Mofang by Roots of Love, and his results  were uploaded to GedMatch. It was hoped that the test would provide some clarity as to how closely related he was to the adoptee. 

It did.

There was no relationship.

The adoptee was devastated. "I don't know if I can trust DNA tests anymore," she explained in my conversation. How could it have gone so wrong?

It shouldn't have gotten this far, of course. Dogmatic claims of a "perfect match" aside, it is known that STR/CODIS tests are susceptible to "false positives" -- when a test indicates a relationship where there is none: 

Because of the shared DNA, when testing the minimum 16 DNA markers for paternity (DDC tests a minimum of 20), there is a slim possibility that the man who is not the possible father could match the child being tested at every location. This scenario can create what is called a 'false positive' result. So can a paternity test be wrong? In this case: yes, even though lab processes were followed correctly.

"Additional tests on an increased number of markers, however, could reveal that the man is not the biological father of the child."  

In other words, because STR (CODIS) tests only look at a very small number of data points (loci), it is possible that two random, unrelated individuals can share those 21 loci, as we saw in the case of this adoptee (The same situation occurred in a murder case in Louisiana where a man matched 34 of 35 loci, and had his life turned upside down by the police who felt that he had committed murder. A full autosomal test later showed no relationship to the DNA of the murderer.) This will result in a false positive. It is hard to overstate how completely devastating this can be to the adoptee and the birth family. It is very, very fortunate that the birth father in the documentary requested the more detailed test, which still matched on twenty-eight of the thirty loci, but failed on two, disqualifying him from being the adoptee's birth father. It wasn't until the autosomal test was done (which should have been done at the beginning) that the non-relationship was discovered. 


There continues to be "controversy" in the Chinese adoption community about DNA testing, but there shouldn't be. The advantages of autosomal testing for locating birth family is abundantly clear. For one, non-parent relationships are detected, allowing for more adoptees to locate birth families. But, as this experience shows, the CODIS test results themselves can be incorrect, with emotionally devastating results.  

If any adoptee has been randomly matched to a birth parent through MyTapRoot, Roots of Love, Nanchang Project, China's police data base, etc., they absolutely must test themselves and the birth family with an autosomal test to verify the match is accurate. 

I reached out to Roots of Love, and they referred me to their website, which states: "When a searcher finds a biological relative who needs to take a DNA test, we cover the costs and test them through either an STR/paternity/CODIS-type test or autosomal test (GEDmatch database)." An August 11, 2022, update regarding the closure of MyTapRoot added that they are "working towards migrating all of the parents in MyTaproot to another STR/CODIS-compatible database that does free matching." It is unknown and undisclosed what CODIS data base will be used going forward, but it is probably "GenGen", which rose from the ashes of MTR.  It seems to this writer that the inability of Roots of Love to provide clarity to the question of what testing will be used going forward indicates that they seemingly will utilize both kinds of tests, even with first-hand knowledge of the STR's significant weaknesses. 

This film clearly shows why STR/CODIS testing should never be used for random birth family matching. The reality is that in a population the size of China's, there will be thousands of random people who will match on the 21 loci used in CODIS testing. Thus, CODIS should only be used for potential target matches, where it is known that the birth parent probably did parent a child. In this case, the birth father was not in the correct time and place to have been the birth father of the adoptee, a point he made clear, ultimately demanding a second test. 

Which begs the question: 

If any random match made using an STR test must be verified by doing a follow-up autosomal test to avoid a false positive, why do STR/CODIS tests to begin with? Why not simply begin with an autosomal test? 

I have never heard a coherent answer to this very simple, but crucially important, question.

I don't want to be seen as picking on Roots of Love. They are simply the organization that facilitated this painful and emotionally devastating false positive. It could just as easily have been any other CODIS testing entity. I am simply wanting to convince everyone that we should no longer (if we ever should have) use STR/CODIS testing on birth families in China. Adoptive families should be the pushers of this change. If an organization, any organization, will not test a birth family you locate for inclusion in GedMatch, look for an organization that will. Don't donate money to any organization that won't act in the best interests of adoptees, birth families, and the the adoption community. If there is any good that comes from the pain of the adoptee as seen in "We Are Family," it should be the commitment of every member of the adoption search community to do the right thing going forward. 

As a community, we should demand that change. 


Postscript: This article/review of "We Are Family" s
et off a firestorm. Almost as soon as it went live, Roots of Love was notified, and they angrily contacted the film maker (who had read my article before publication) and demanded that their part of the film be removed (not possible since the film had already been broadcast in Belgium). The film maker did contact Youtube, and requested that the video clip from this article be taken down, which they did. By that time over 700 readers had seen the video.

There have been many opportunities for Roots of Love to do the right thing over the past three months. First, they could have made the adoption community aware in June that one of their tests had had an issue, and that they were going to change their protocol to prevent a false match from occurring in the future (announcing that they would be testing with autosomal tests exclusively would have accomplished this). Second, they could have issued a statement yesterday indicating that they had had discussions, and that things were going to be done differently in the future to prevent something like this from happening again. I gave them a head's up over the weekend, giving them a chance to get ahead of the curve on this, but they refused.

The very real issue is that IF the birth father had not requested a second test, the adoptee would have gone the rest of her life thinking she had located her birth family. She would have stopped searching, and therefore never found her actual birth family. The false positive that resulted from the STR/CODIS was potentially catastrophic.

Rather than address this main issue, instead Roots of Love is attempting to bury it, and keep the adoption community in the dark.