Monday, May 7, 2012

"Finding Your Roots with Henry Louis Gates, Jr." - DNA in the Eighth Episode


Featured last night on the eighth episode of Finding Your Roots with Henry Louis Gates, Jr. were Martha Stewart, Margaret Cho and Dr. Sanjay Gupta. Each of these "trailblazers in media" descend from very recent immigrants to the United States and thus face special challenges in tracing their family trees. The good news is that I was granted the reprieve I hoped for last week and the bad news is that I was granted the reprieve I hoped for last week. There was very little genetic genealogy in this episode, so this will be a relatively quick and easy review.

"Domestic Goddess" Martha Stewart- genetics at play?

Early on in Martha's segment after discovering that many of the branches of her family tree were populated with ancestors who were "highly skilled in the domestic arts" - like basketweavers, iron workers and seamstresses, Dr. Gates commented that this "makes you believe in genetic predeterminism," the idea that an individual's development is preordained by heredity. Later, Martha mentioned her dog is named "Genghis Khan" after Dr. Gates' team linked her ancestry to the Tatar people who were subjugated under Khan and they laughingly discussed the possibility that she could be descended from him. (Filed under "things that make you go 'Hmmm'".)

Martha with her family member Genghis Khan II

The DNA portion of the show wasn't until the very end of the episode (starting at 46:40) and started with an analysis by  23andMe of Martha's direct maternal line DNA (mtDNA). (Mitochondrial Haplogroups are included with 23andMe's genome scan.) This ancestral line had been traced back by Dr. Gates' genealogy team to a maternal ancestor with the last name Albiniak who lived in the town of Janów, which apparently implies that the family was Muslim. Martha's mtDNA haplogroup was determined to be W6, a Central Asian haplogroup which, according to Dr. Gates, spread to the area around modern day Pakistan, thus supporting his genealogists' conclusion regarding a potential Islamic heritage for Martha's direct maternal line (mother's mother's mother's mother, etc...). Although this is quite an unexpected and intriguing result for someone who seems as WASPy American as apple pie, Martha didn't appear to be particularly surprised by the news.

Martha learning about her unusual mtDNA haplogroup

A website dedicated to the W haplogroup states that W6 reaches its highest concentrations in Georgia at 5.2% compared to 2.7% in Pakistan. Wikipedia states that Haplogroup W, not the subclade of W6, is found in Pakistan. I was unable to find enough information on this relatively rare haplogroup to reach any definite conclusions on its relevancy to Martha's family history.

Distribution of Martha's mtDNA Haplogroup W6

Next, Dr. Gates revealed Sanjay's mitochondrial DNA haplogroup to be U2c, which he said occurs most often in the Sindhi people of Southern Pakistan. This result is not surprising for a person of Indian heritage like Sanjay and coincided with his mother's family's recent migration (1947) from the area that is now Pakistan. This results suggested that Sanjay's direct maternal ancestral line was likely in this region for thousands of years. It would have been neat to find out what his paternal line haplogroup (Y-DNA Haplogroup) was too, but Dr. Gates chose to focus on mtDNA exclusively in this episode.

Sanjay's mtDNA Haplogroup U2c

Margaret was in for a bit of surprise when her mtDNA haplogroup was reported as D5a2a1b. This haplogroup reaches highest concentrations in China, not Margaret's family's homeland of Korea. In fact, D5a is extremely rare in Korea, appearing in less than one percent of the population. Further, Dr. Gates mentioned that "another test" showed that her paternal haplogroup also traces back to China instead of Korea. This other test would have been a Y-DNA Haplogroup test. Since Margaret herself does not have a Y-Chromosome, to reach this conclusion, Dr. Gates team must have tested her father or a brother. Unfortunately, the specific Y-DNA Haplogroup was not revealed. I would have liked to see it if only for the reason that, in my experience, Asian DNA is not widely discussed and would benefit from more visibility in our research and discussions.

Margaret's mtDNA Haplogroup D5a2a1b

Even though mtDNA haplogroups were the only DNA results explored in this episode, it was very interesting because each of the guests had a relatively rare haplogroup, at least as far as what exists in our databases at this point in time. (I searched the list of about 1000 people that I am sharing with at 23andMe and none of them had any of the three mtDNA haplogroups mentioned here. I also searched the corresponding haplogroup projects at FTDNA and found very few from these subclades.) Haplogroups are indicative of deep ancestry and are not generally genealogically relevant, however when the documentary paper trail runs out, they can provide clues as to the family's historic location and migratory pattern.  Dr. Gates explains it like this, "Certain DNA tests act like a genetic global positioning system, providing valuable clues about where our ancestors once lived." Apparently Dr. Gates' team used 23andMe's genetic scans to determine these haplogroups. This is a little surprising since haplogroup research is actually more of a specialty of Family Tree DNA, the other DNA testing company often featured in the series. 23andMe includes this information with their autosomal DNA test, but offers no further information beyond the haplogroup designation. At Family Tree DNA, a person can get the detailed list of the exact STRs (Y-DNA) and mutations (mtDNA), thus enabling matching with other individuals in the large FTDNA databases containing these specific results. (I suggest the Y-DNA 37 marker test and the mtDNA Plus.)

Investigating the family trees of Martha, Margaret and Sanjay

On my wish list would have been admixture breakdowns for the guests (remember those pie charts in earlier episodes?), especially Martha and Sanjay. Martha's results could have been very interesting if any of her Tatar autosomal DNA remains. I'm not sure what her breakdown would look like, but I imagine there would be an Asian component. Since her maternal grandmother was an Albiniak and her genetic contribution makes up about 25% of Martha's genome, it is certainly plausible that some autosomal genetic traces of her Tatar ancestors remain. (I note from an entry in Wikipedia that the Muslim Tatars were allowed the unusual right of intermarriage with Catholics in Poland, which may help to account for that portion of Martha's family tree.)

I would have also liked to see a breakdown of Sanjay's genetic ancestral origins since most Indians will have a substantial mixture of both Asian and European autosomal DNA. It is always interesting to me to see how these two components balance out. Margaret's autosomal DNA likely wouldn't have revealed anything significant since the major testing companies have yet to commercially analyze East Asian DNA in any great detail, but you never know.

I also really missed seeing the familiar faces from the two DNA testing companies regularly featured in this series.

Next week we will delve back into the genetics of African Americans with guests John Legend and Wanda Sykes who are both descended from free people of color.  Now that I've had my break, I hope this episode is packed full of DNA research on these intriguing family trees, especially since there are only two episodes left!



I have been writing a review of the DNA testing used in each episode:
Week 1- Episode 1 & Episode 2 - Harry Connick Jr. & Branford Marsalis; Cory A. Booker & John Lewis
Week 2- Episode 3 - Barbara Walters & Geoffrey Canada

Week 3- Episode 4 - Kevin Bacon & Kyra Sedgwick
Week 4- Episode 5 -  Rick Warren, Angela Buchdahl & Yasir Qadhi
Week 5- Episode 6 - Robert Downey, Jr. & Maggie Gyllenhaal 
Week 6 - Episode 7 - Condoleezza Rice, Samuel L. Jackson and Ruth Simmons

2 comments:

  1. Have you tried to get in touch with Gates to see if he will share more details with the community that is attempting to analyze and use DNA results. Specifically of course to find birth lineages in the case of adoptees. It would be good to get additional insight from him on the cases he has actually solved rather than theoretical insights

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  2. One (unintentionally) funny thing - the genealogy book for Margaret Cho's family that they show at 40:23-40:28 is upside down.

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