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

The sixth episode of Finding Your Roots with Henry Louis Gates, Jr., investigating the mixed ancestry of Robert Downey, Jr and Maggie Gyllenhaal, aired last night on PBS. These two actors not only share a profession, but both have a mixture of Eastern European Jewish ancestry as well as deep American roots. Because of these commonalities, I thought their stories worked well together. I was thoroughly entertained by this episode for three reasons: 1) I love Robert Downey, Jr., 2) I discovered that Maggie is my cousin through our shared 10th great grandfather John Lothrop and 3) The appearance of Bennett Greenspan, President of Family Tree DNA (or as Professor Gates called it "FamilyTreeDNA.com", which I am sure was much appreciated).

Bennett Greenspan on "Finding Your Roots with Henry Louis Gates, Jr."

Unfortunately, the DNA portion was only about five minutes long again this week (starting at 43:00), nevertheless it felt a bit more substantial to me than last time. I was happy to see a number of different tests featured: 23andMe's Ancestry Painting, FTDNA's Population Finder and mtDNA testing.

Robert Downey, Jr.'s "Ancestry Painting" from 23andMe

First, Robert Downey, Jr., whose father is half Jewish, was presented with a pie chart of his 23andMe Ancestry Painting, which breaks down a person's genetic ancestral origins into three populations - European, African and Asian. (Note - this test is included in the 23andMe Personal Genome Service and is presented as a chromosomal chart rather than a pie chart.) Dr. Gates has repeatedly stated that this test reveals "European, African and Native American ancestry", however I would like to remind readers that the Asian reference population simply "stands in" for Native American. 23andMe does this because the genetic makeup of the two populations is similar, but in reality, this is not quite the same as having reference samples from Native Americans and the two should not be confused with each other. For instance, a person could show Asian DNA on their Ancestry Painting, but one should not automatically reach the conclusion that they have Native American ancestry because they may have ancestors from China, Japan, Korea or any other Asian region. If a person has reason to suspect that they possess Native American ancestors and knows of no other Asian ancestry, then this test is useful for that purpose. As is typical of most people, RDJ guessed that his ancestry would be more "interesting" than it was and seemed disappointed to learn that his Ancestry Painting showed 100% European ancestry. As I have mentioned before, this actually encompasses all of Europe, including the Middle East, so it doesn't rule out RDJ's Jewish ancestry.

Robert Downey, Jr.'s "Population Finder" from Family Tree DNA

Next, Dr. Gates presented RDJ with what I believe was his Population Finder admixture from Family Tree DNA. (The PopFinder feature is included with the Family Finder test.) This test broke down RDJ's ancestral origins a bit more, showing that he is about 20% Middle Eastern or Jewish.  That is slightly under what we might expect for him with a father who is half Jewish, so his one Jewish grandparent may have had a little something else mixed into his/her ancestral origins.

Later, Dr. Gates sat down with Maggie to discuss her mitochondrial DNA (mtDNA) which is inherited straight down the maternal line, passed from mother to child as far back "as you can think" enthused Maggie. Maggie's mom is Jewish, so it makes perfect sense that Maggie's mtDNA has been inherited from one of four Jewish founding mothers who lived thousands of years ago. The voiceover explained, "Scientists have concluded that 40% of Eastern European Jews share genetic lineages that reach back two to three thousand years, remarkably to just four women...today about 3.5 million people descend from one of these four maternal ancestors." Haplogroup Project Administrator and genetic genealogist Vince Tilroe points out that Bennett Greenspan and Professor Gates were most likely speaking of mtDNA Haplogroups K1a1b1a, K1a9, K2a2a, and N1b when referring to the four Jewish maternal lines. These were identified in the 2006 study by Dr. Behar, "The Matrilineal Ancestry of Ashkenazi Jewry: Portrait of a Recent Founder Event".

Bennett Greenspan of FTDNA explaining Jewish DNA to Dr. Gates

Bennett further explained that Maggie had "hit the jackpot" with about 150 exact matches in Family Tree DNA's mtDNA database.  Bill Hurst, Administrator of the mtDNA Haplogroup K Project and a leading expert on this haplogroup, theorizes that if Maggie's mtDNA haplogroup is K, she likely falls into the K1a1b1a ancestral haplotype. Hurst explains that this haplotype's match numbers most closely coincide with the those that Bennett cited from FTDNA's database. At the HRV1/HRV2 level of testing, this haplotype now has 194 exact matches, but at the time of filming may have had closer to 150. He also notes that K2a2a is now called K2a2a1 due to recent discoveries. (There are three levels of mtDNA testing offered by Family Tree DNA which you can read about here.)

At the end of the episode Professor Gates discussed the question of "nature versus nurture" with his guests and asked Robert Downey, Jr. if he feels that his ancestral past has shaped who he is today. In answer, RDJ insightfully commented, "I don't see how it couldn't...it's informing you whether you're conscious of it or not, so probably better to be conscious." The episode ended with RDJ expressing his feelings about this experience with Dr. Gates, explaining that he felt that this was just the beginning of his journey of self-discovery.

I hope this show has also inspired all of you to begin (or continue) the journey into your ancestral roots. See you next week when we review the genetics of Samuel Jackson, Condoleezza Rice and Ruth Simmons. The television listing says that the show will be using DNA to "determine which parts of Africa their ancestors came from." That sounds promising!


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

"Finding Your Roots with Henry Louis Gates Jr." - DNA in The Fifth Episode

The fifth episode of Finding Your Roots with Henry Louis Gates Jr., which featured religious leaders Rick Warren, Angela Buchdahl and Yasir Qadhi, aired last night on PBS. This means we are halfway through the miniseries! As we have progressed through the episodes it appears to me that Gates and his team are featuring DNA testing progressively less and less. This is a shame and I hope this trend will reverse itself in the second half of the season.

The DNA portion of the show last night comprised only about 5 minutes (starting at 44:55), but drew some interesting genetic comparisons between guests of different religious backgrounds, demonstrating again that DNA testing is "deconstructing the notion of race" (quote from Gates in an earlier episode). Qadhi's Y-DNA haplogroup or what Gates referred to as his "paternal haplogroup" which was inherited from his father's father's father, etc... is J2. This haplogroup is common among those with Indian ancestry like Qadhi, but also "reaches levels of about 20% in Ashkenazi Jews". Qadhi said that he didn't find this too surprising since "Muslims and Jews consider themselves cousins...(as) descendants of Abraham."

Yasir Qadhi reviewing his Y-DNA Haplogroup

Qadhi also had a surprising "matrilineal cousin" in a guest from an earlier episode -  Barbara Walters - with whom he shares his mtDNA haplogroup which was inherited from his/her mother's mother's mother, (etc...). Unfortunately this haplogroup was not revealed in either episode, so we can only guess what it may be. I would imagine that in each case, while sharing the major haplogroup, Qadhi of Indian ancestry may belong to a slightly different subclade than his Jewish cousins. (See the Y-Haplogroup J Project for details.)

Less surprising, Rabbi Buchdahl is also a distant cousin to Barbara Walters. Gates said that Buchdahl and Walters share a common ancestor within about the last 300 years. He mentioned "three segments" in common between them. This test was clearly an autosomal DNA test by 23andMe or Family Tree DNA's Family Finder. Normally three matching segments of DNA would imply a significantly closer relationship than distant cousins, but among the highly endogamous Ashkenazi Jewish population, this is not uncommon. I was pleased to see Gates team incorporating all three types of DNA used for genealogy in this segment.

Angela Buchdahl reviewing her father's Warnick Y-DNA (?)

In the voiceover starting at 46:15, Gates explains, "DNA Analysis can tell us...where our earliest ancestors originated thousands of years ago, to whom we might be related today and the percentages of our African, European and Asian ancestry over the past 500 years." I thought that this may have caught some viewers' interest, so I wanted to detail which tests he was referring to in that comment.

The first part of the quote - "where our earliest ancestors originated thousands of years ago" -  refers to deep ancestry that is revealed through our Y-DNA and mtDNA haplogroups, tracing the migration of mankind. You can learn your haplogroups from 23andMe's DNA test or by taking the Y-DNA STR test and/or the mtDNA test at FTDNA.

Next, "to whom we might be related today" refers to autosomal DNA tests that match you with cousins from your more recent ancestry by examining matching blocks of DNA between testers. These types of autosomal tests are currently only offered by 23andMe and FTDNA. 23andMe's "Relative Finder" feature is included in their single test and FTDNA's test for this purpose is called "Family Finder".

Lastly, "the percentages of our African, European and Asian ancestry over the past 500 years" refers to biogeographical ancestry analysis or admixture tools like 23andMe's Ancestry Painting or FTDNA's Population Finder. In this case, he was specifically referring to 23andMe's Ancestry Painting. This is the most basic of genetic ancestral origin tools only using the three populations mentioned. FTDNA's Population Finder breaks down genetic origins into more granular populations and 23andMe's Ancestry Finder feature does so as well, with a somewhat different approach.

Earlier episodes have shown the pie chart with the guests' ancestral origins or genetic admixture by percentages. In this episode, we caught a glimpse of Pastor Rick Warren's dark blue chart, signifying 100% European. While he and Gates laughed at this result, it isn't necessarily as boring as it might sound since, in this case, "European" encompasses ancestry from all over Europe including Russia, France, Germany, Finland, the British Isles, the Middle East, Scandinavia and many other countries.

It would have been interesting to see all of the guests' Ancestry Paintings in this episode because there would have been much commonality between them. As a person of Indian heritage, Qadhi would have likely possessed a large European component and a smaller Asian one and Buchdahl's chart, being half Jewish and half Korean, would have probably been equally split between Asian and European. (Upon further review of the episode, it appears that I was correct - see below.) The specific differences between the Asian and European ancestry among the guests would only be revealed with a more detailed breakdown, such as FTDNA's Population Finder or 23andMe's Ancestry Finder.

Angela Buchdahl looking at her "Ancestry Painting"

Next week we will be privy to details of the family trees (and hopefully DNA!) of movie stars Robert Downey Jr and Maggie Gyllenhaal. That sounds like fun! See you then...


I have been writing a review of the DNA testing used in each episode:
Week 1 - Episode 1 and 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