What is the difference in Y-DNA and mtDNA?
A3. Both forms of DNA can be compared to a family crest — in that they are unique to that line. The mtDNA identifies the maternal line and the Y-DNA identifies the paternal line. Mitochondrial DNA is passed by a mother to her children. This makes it useful for tracing the maternal line — a person’s mother, her mother’s mother, her mother’s mother’s mother, and so on. Every woman descended from the same ancient female ancestor will carry virtually identical mtDNA. The Y chromosome is carried only by a man and the son receives a virtually identical copy from his father. Every man descended from the same male ancestor will have very similar Y-DNA though it changes more often than does the mtDNA.
