The Genetic Genealogist

Randy Seaver at Genea-Musings (“I’m Puzzled by DNA Claims on ‘Faces of America’”) writes about the fourth and last episode of “Faces of America,” a PBS documentary series investigating the ancestry of several famous people in America. This fourth episode included several different types of genetic genealogy to examine the ancestral origins and relatedness of the show’s members.

1. Whole Genome Sequencing by Knome

The first type of genetic genealogy was whole-genome sequencing by Knome of Henry Louis Gates and his father. This analysis examined Henry’s (“Skip’s”) genome for medical conditions and physical traits, and also compared his DNA to his father’s, thereby allowing them to deduce the entire DNA contribution from his deceased mother. This segment was actually quite moving, as Dr. Gates was able to establish this intimate connection to the mother that he and his father obviously missed very much.

2. SNP Analysis by 23andMe

The second type of analysis was large-scale SNP analysis of everyone’s genome by 23andMe. The show primarily focused on the Ancestry Painting, which uses information from throughout the entire genome to determine a very rough estimate of your ancestry. Ancestry Painting breaks down the genome into three categories: Asian/Native American, European, and African. Stephen Colbert, for example, was 100% European, while Eva Longoria was 70% European, 27% Asian/indigenous, and 3% African. I don’t recall any mention or use of 23andMe’s medical or physical trait analysis in the show.

3. mtDNA and Y-DNA Haplogroups

The third type of genetic genealogy was haplogroup testing. In this segment, Dr. Gates spoke with Dr. Bryan Sykes of Oxford Ancestors, which was interesting because it was the first time I’ve ever seen him speak. There didn’t appear to be any surprises here.

4. Mysterious Genomic Comparisons

The fourth type of genetic genealogy testing in the episode is what has caused so much confusion among genealogists. Dr. Gates introduced David Altschuler and Mark Daily as “research geneticists at the Broad Institute.” According to Dr. Gates, Altschuler and Daily have “pioneered a new kind of genetic analysis that can determine if any two people share a common ancestor within the last several centuries.” Although Dr. Gates repeatedly said within the last “250 years”, the scientists repeatedly said “hundreds of years.” A slight difference perhaps, but I tended to disregard the “250 years” as more of a simplification by Gates for purposes of the show rather than any actual limit discussed by the scientists. Regardless, this doesn’t make their analysis any more clear.

Unfortunately, I have been unable to locate any discussion, literature, or publication by Altschuler or Daily (or anyone else) discussing this “new kind” of genetic analysis. If you’re familiar with one, please point it out in the comments so that we can understand their analysis.

Interestingly, the members of the series apparently did not match each other in 23andMe’s Family Finder, since the 23andMe system would have picked up on that, and further analysis would not have been necessary. And since it appeared that they did NOT undergo further testing, I imagine they used their 23andMe data for the analysis by Altschuler and Daily.

As an example of this comparison, according to Altschuler and Daily, Yo-Yo Ma (who was 100% Asian in his 23andMe Ancestry Painting) is related to Eva Longoria (who was 70% European, 27% Asian/indigenous, and 3% African) within the last few centuries. It obviously wasn’t through Native American DNA since any connection there was many, many thousands of years ago. Does Longoria have more recent Asian DNA perhaps? It seems unlikely (but is certainly not impossible). The fact that this was simply glossed over was an oversight.

I’m having a hard time understanding the results from Altschuler and Daily.  Can anyone else shed any light on their analysis?

Conclusion

Despite the confusion created by the fourth type of genetic analysis, I really enjoyed this episode of Faces of America. As always, it was interesting and entertaining to watch them receive their results and explore their ancestry.

What are your thoughts?