The mitochondrial DNA genealogy is the study of a person’s mother’s family line of maternal ancestors. This DNA is passed down from mother to each of her children exactly as she has it, with no mutations, except in the very rare instances.
Because of the traditions in our society of the wife taking her husband’s last name, a surname genealogy trace of the female line of the family tree is more difficult. On the flip side, since this DNA strand is more stable than the Y DNA, more conclusive results can be determined for the testing of it.
The mt-DNA is sometimes referred to as the Full Genomic Sequence (FGS). Since this DNA changes or mutates so rarely and slowly over time, a perfect match to an ancestor can be found who lived several hundred years ago.
The mtDNA of a person is not located in the nucleus of the sample cell but in the cytoplasm. This is the cellular material that is passed down from generation to generation. For those that wish to test this strand of DNA, they must be aware of one fact. The males receive this strand from their mothers, but that is where it ends.
Males pass on only the Y DNA chromosome. Because of this, a male has no genetic marker from their grandfather’s on their mother’s side. For this part of a family tree to be traced, a sample from a close relative, like a male sibling of the mother, would need to be obtained.
For this reason, the old saying that sons were the only carriers of the family blood line is more accurately stated as the only ones passing down the family DNA line. The mitochondrial DNA genealogy is only for determining the mother’s side of the family from child to female.