Genetic genealogy is the combining of the science of genetics to traditional genealogy. Genealogy is the study of family history. which traditionally has relied on tracing back through the records of your family descent. a chart showing genealogical descent is a pedigree and many people in the old world countries like europe and in newer countries like USA, Canada or Australia have attempted to trace their own family tree from such records in their believed country of origin of their ancestors. Genetic genealogy combines DNA testing with traditional charting methods to help determine and substantiate the level of genetic relationship between people but also analysing Mitochondrial DNA, Mitochondrial Eve, Y chromosomal Adam and Ancient Migrations. For example, because your autosomal DNA is inherited from both parents, but Y-chromosomal DNA (Y-DNA) is inherited only from father to son, and mitochondrial DNA (mtDNA) is inherited only from our mother this helps to track down both sides of your ancestry . MtDNA also passes down nearly unchanged through generation to generation. So you share the same mtDNA-type as your mother, your maternal grandmother, your maternal great-grandmother and so on. The exact same mtDNA code thus can trace your direct genetic line back to the point at which a natural mutation in the mtDNA code occurred. In this way, e DNA Services use advances in genetic understanding and laboratory techniques in order to help identify your maternal lineage through a mtDNA tracing service. By analysing and comparing your own distinct mtDNA within their database of many thousands of other mtDNA samples from all over the world, they are able to find out much more about your ancestry. For example family genealogists trying to discover whether 2 people with the same surname are related, may use Y chromosomal tests. This is possible because in many cultures, family names or surnames are passed down by the father just like the Y chromosome, and so by comparing yours with theirs to see if they match a relationship can be confirmed or disproved.. .