DNA USA: A Genetic Biography of America

America’s gorgeous mosaic emerges from its DNA in this fascinating if sometimes muddled treatise on genetics and genealogy. Oxford geneticist Sykes (The Seven Daughters of Eve) traveled across the United States collecting DNA samples, recording family histories, and gazing out the window of his train car. (His evocative landscapes are one of the book’s chief pleasures.) The resulting “chromosomal portraits,” painted by analyzing markers that correlate with African, European, or Asian–Native American populations, reveal DNA tell-tales of unsuspected centuries-old migrations and mixings: Mexican-American Catholics descended from Spanish Jews; white Southerners with substantial African-American ancestry; possible journeys from Europe to North America 10,000 years ago. Sykes gives lucid, entertaining explanations of new genetic techniques and their startling success at tracing familial ties across continents and millennia. But he often flounders in contradictory interpretations as he veers between deploring artificial ethnic categories and subtly endorsing them (“My pancreas functions on a combination of both African and European genes”)—his genetic testing company, Oxford Ancestors, helps British customers peg their forefathers as Viking, Saxon, or Celt. Still, Sykes’s history of hidden kinships and epic wanderings captures the imagination. Photos. Agent: Luigi Bonomi, Bonomi Associates (U.K.). (May)