Friday, 6 October 2006

Blood of the Isles: Book Review

With his previous international best seller, The Seven Daughters of Eve, Bryan Sykes gained a considerable reputation for popularization of genetics applied to human history. Blood of the Isles follows in the mould. The scope is the area geographically called the British Isles, which in order to assuage sensitivities he simply calls “The Isles.” It is based on Sykes' analysis of 50,000 DNA sequences, including many collected during the Oxford Genetic Atlas Project, which started in 1996.

The bulk of the book, chapters 8 - 17, takes Ireland, Scotland, Wales and England in turn, reviews geography, mythology, early writing and archaeological evidence, then reports DNA findings in that context. Sykes weaves in the personal story of collecting the DNA samples. Along the way you learn of the Neanderthal brothers of Tregaron, and where to get the best ice cream in Lampeter.

I personally found the liturgy of kings and nobles used as context uninspiring. Some of these men, Sykes claims, had an especially large number of descendants explaining some of the uniformity in DNA. On the other hand, I enjoyed two of the early chapters, about early surveys of physical characteristics; hair and eye colour, and blood type, which provide a nice response to FAQs.

One group likely to find this book thin gruel will be genetic genealogy enthusiasts. They may prefer to skip to the summary chapter 18 and the appendix. The basic data used is low resolution, less than the full range of the currently analyzed HVR1 for mitochondrial DNA, and mostly seven, sometimes ten, markers for Y-DNA. There is an appendix with summary tables, and a welcome web site with detailed data. I searched in vain for a listing of the marker profiles used to define groups.

These days, when much more detailed DNA analysis of mtDNA and Y-DNA is commonplace, this analysis seems rather broad brush, reflecting the state of the art in 2002 when the last samples appear to have been taken. It does show, in a non-technical presentation, that much insight can be gained from careful analysis of low resolution DNA data.