So - if my great grandmother was a Douglass - on my mother's side - if either she or I got tested it would only show Europe, not which clan, etc? I would have to find one of my great grandmother's brothers in order to get that information - correct?? Julie Pat Duncan <GenNutLdn@msn.com> wrote: This might help explain the differing values of Y-DNA vs mtDNA testing. >From the Family Tree DNA site: The Y chromosome is transmitted from father to son. Testing the Y chromosome provides information about the direct male line, meaning the father to his father and so on. The locations tested on the Y chromosome are called markers. Occasionally a mutation occurs at one of the markers in the Y chromosome. Mutations are simply small changes in the DNA sequence. They are natural occurrences and take place at random intervals. Overall, they are estimated to occur once every 500 generations per marker. Mutations can sometimes be valuable in identifying branches of a family tree. Y-DNA testing can be used to confirm the paper genealogical research for your family tree. It can determine which family trees with the same or variant surnames are related, and can provide clues to help you with your genealogy research. mtDNA is passed from mother to child. Since only females pass on their mtDNA, testing the mtDNA tells about the mother, to her mother, and so on along the direct maternal line. Both males and females receive mtDNA from their mothers, so both men and women can test their mtDNA. While mutations occur in mtDNA, the rate of mutation is relatively slow. Over thousands of years these mutations build up so that one female line will have a sequence distinguishable from another. As people spread throughout the world, mutations occasionally occurred in different populations over time. This allows us to test the mtDNA to identify the world origin of a person's lineage. mtDNA is tested and the result is compared to a reference sequence called the Cambridge Reference Sequence (CRS). By comparing an mtDNA sequence to the CRS, we can identify the ancient lineage to which you belong, called the haplogroup. Many haplogroups are continent-specific and some of their branches are region-specific. Pat Duncan GenNutLdn@msn.com --------------------------------- Choose the right car based on your needs. Check out Yahoo! Autos new Car Finder tool.