Discover the answers to your family history mysteries using the most-cutting edge tool available to genealogists. This plain-English guide, newly revised and expanded, is a one-stop resource on genetic genealogy for family historians. Inside, you'll learn what DNA tests are available, with up-to-date pros and cons of the major testing companies (including AncestryDNA) and advice on choosing the right test to answer your specific questions. For those who've already taken DNA tests, this guide will demystify and explain how to interpret DNA test results, including how to understand ethnicity estimates and haplogroup designations, navigate suggested cousin matches, and use third-party tools like GEDmatch to further analyze data. Inside, you'll find: Colorful diagrams and expert definitions that explain key DNA terms and concepts, such as haplogroups and DNA inheritance patterns Detailed guides to each of the major kinds of DNA tests: autosomal-DNA (atDNA), mitochondrial-DNA (mtDNA), Y-chromosomal DNA (Y-DNA), and X-chromosomal DNA (X-DNA) Tips for selecting the DNA test that can best help solve your family mysteries, with case studies showing how each test can be useful in research Information about third-party tools you can use to more thoroughly analyze your test results once you've received them Test companion guides and research forms to help you select the most appropriate DNA test and organize your results and research once you've been tested