27 June 2013

DNA USA paints a genetic picture but misses its mark

Bryan Sykes, DNA USA: A Genetic Portrait of America (New York: Liveright Publishing Co., 2012)

In the last 10 years or so, genealogists have studied the mysteries of DNA and its potential for furthering family research. Collected from males, Y-DNA takes us down the surname path from our father’s father’s father and so on, while mtDNA travels back from our mother’s mother’s mother. 

In DNA USA, Bryan Sykes has a new test, the chromosome paintings or profiles done by the personal genome company, 23andMe. Instead of using the X and Y chromosomes, this test splits the 22 pairs of autosomes in half, separating the two copies of each chromosome, and then highlighting which DNA segments correspond to one of three continental origins (Europe, Africa, Asia). The results can be further analyzed by marking 146 genes on the chromosome portrait to show which continental origins contributed to 11 different body systems (such as pigmentation, eyes, digestion, and immune system).

In three months, Sykes tours cross-country, stopping here and there to interview people working in the field of genetics, such as Bennett Greenspan of FamilyTreeDNA and Dr. Rick Kittles of African Ancestry. The interviews are often on-target to probe deeper into a subject, such as Ashkenazi DNA, but it does seem to be a balancing act so the book wouldn’t sound like an advertisement for 23andMe. (Sykes, a professor of human genetics at Oxford University, also founded his own commercial company, Oxford Ancestors, as an offshoot of private genome research.)

His travelogue, peppered with American movie references, takes him from Boston to Chicago, Denver, Salt Lake City, and San Francisco by train, with a few side trips along the way. Although he writes like a great adventurer, his route is not as random as it sounds. He has specific goals and stories to tell in his book, and his travels correspond to them. However, Sykes chooses to bypass the Southeastern states because he was able to pick up DNA samples from two African-American women from Atlanta at a hotel convention in California. Later, though, he regrets not being able to sample DNA from a Ku Klux Klan member to reiterate his point that many European Americans from the South show traces of African DNA.

The Faces of DNA

On his excursions, Sykes collects DNA samples from 25 individuals. Yes, out of 316 million people (U.S. Census Bureau) living in the 3.7 million miles that make up the United States, Sykes chose only 25 people for his genetic portrait, saying that to do more would be ridiculously expensive. And so, he chose to backfill our genetic story with previous research, both his own as well as others in the field. After all, America is the melting pot, a cross-section of the continents. Sykes already covered Europe in the bestselling The Seven Daughters of Eve (2001) and, more specifically, the British in Saxons, Vikings, and Celts (2007). When he rehashes his previous books, Sykes is not as engaged in the storyline and tends to add more travelogue and movie references. But with new material, particularly the chapters on the Jews and the Africans, his interest is piqued again and it shows.

America's story starts with Native Americans. Due to other scientists' prior unsanctioned medical research and the legal backlash that followed, however, Sykes avoids collecting DNA from them. He relies on earlier research, shored up with his Polynesian studies. When he travels to tribal lands, Sykes judiciously leaves his DNA kits behind, knowing the scientist in him could overwhelm common courtesy. In the book, he acknowledges the spiritual beliefs of the Native American creation stories and at the same time, he wants to prove their genetic profiles tell a different story.

Finding an Audience

Like his other books, DNA USA is written not for the scientific community but for a popular audience—including genealogists, some of whom are featured in the book. These genealogists prepared ancestral charts, told detailed stories of their forebears, and provided DNA for Sykes to analyze. He admits “not being a genealogist” (p. 75), though “the speed and enthusiasm with which the American genealogy community has embraced genetics has been truly astounding” (p. 72).  

So, if DNA USA was written for a focus group, it is the American genealogist. That’s why it’s disconcerting that throughout the book Sykes repeatedly refers to the New England Historic Genealogical Society (NEHGS) by the wrong name. Although this may seem a trivial point, the mistake suggests potentially sloppy research and fact-checking in other parts of the book. (DNA USA could have used more proofreading to pick up other typographical errors as well.) In addition, there are no footnotes or a bibliography—another pet peeve of genealogists.

However, thumbing through the chromosome paintings and recognizing faces from the DNA volunteers—with their high-level pedigree-researching skills—prove how fascinating and potentially useful genetic testing is for genealogy.