DNA USA: A Genetic Biography of America

I agree with other reviewers that there are some issues with this book, although I'm not sorry I picked it up. I won't belabor the point that the handful of people used to represent the rich genetic background of the US wasn't remotely representative.

What really bothered me was a section on page 158 of the hardcover version. Sykes proposes that all living homo sapiens descend from a “universal ancestor” who originated about 1,900 years ago. The model used to calculate this estimate is supposed to take the impact of cross-continent migration. So, the figure of 1,900 years wouldn't seem to support estimates related to the ancestry of Native Americans. If someone can explain why Sykes' theory is correct, I'd love to hear the explanation.

However, the book is enjoyable and does provide some interesting stories, such as the Scottish surname investigation and how mitochondrial DNA is passed.