In the introduction, Bettinger contrasts the imprecision of genealogical records with the scientific exactitude of DNA information. But he then points out that interpretation of DNA results is still very much in its infancy, and therefore can introduce errors and inconsistencies. Genealogists need to use both tools together to build the best picture available.
The book is organized into three sections:
- Getting started
- Selecting a test (mitochondrial, Y-chromosomal, autosomal, or x-chromosomal)
- Analyzing and applying test results
Additional information includes a glossary, and appendices:
- A Comparison Guide (flowchart and tables to help you decide which test and service to use)
- Research forms
- More resources (books, blogs, websites)
The book includes helpful features like summaries of the salient points of each chapter. The writing is clear, and the layout is colorful and pleasing. I especially liked the chapters on common misconceptions, and on analyzing complex problems with DNA. Case studies are used to illustrate uses of the different types of tests.
Bettinger reminds us that the first publicly available DNA testing was in this century (2000), though it was famously used before that in forensic tests on the remains of Tsar Nicholas's family, and in proving that Thomas Jefferson fathered children with his slave-mistress Sally Hemings. It was only in 2005 that both Ancestry's and 23 and me's databases reached the one-million mark. So DNA testing is very young and will continue to evolve. This book will be useful in getting you started on your DNA journey.