Using mtDNA in Genealogy

USING mtDNA in GENEALOGY

mtDNA

Passed from mother to children; however only daughters pass it on to their children

Mutates much more slowly than Y-DNA

Match on the high resolution test gives 50% probability that the MRCA is no more than 28 generations ago, or about 630 years ago

CONTRAST to Y-DNA:

Y-DNA: Donate a sample and wait for match with other sample donor(s)

"Shotgun approach" -- fire two or more "shotguns" at a target and eventually a bead from one will hit a bead from another

MUST be male donor (not adopted) descended from earliest known male ancestor. Same surname from oldest known ancestor to donor.

mtDNA: Need to have specific women to test & some idea of the relationship between them.

"Darts Approach" Known woman is the bull's eye. Specific samples are aimed at a match with her.

Donor can be male or female

Sample Case 1

Between 1800 and 1830 five girls marry in a certain county. During that period only three men with the same surname are present in the county that could possibly be the fathers of these women. Unless the men's wives are all sisters, the daughters of each couple will have different mtDNA. There is one known daughter of one man who has an alll female lineage to a descendant who is willing to donate a sample of mtDNA. There are all female lines of descent for the other women, but nobody knows which woman belongs to which couple.

Obtain a sample from the KNOWN daughter of Couple #1. We now have the mtDNA "signature" of the wife in Couple 1.

Obtain samples from the descendants of the other women. Compare them to the KNOWN daughter.

The 2 girls who match the known daughter should be her sisters

The other 3 girls who do match the known daughter, nor do they match each other. We also now know

1. These girls are not sisters to the KNOWN daughter, nor to each other.

2. There is one more unaccounted for set of parents. The most obvious explanation, of course, although it is not necessarily the case, is that one the girls was a sister of one of the men. If any of the men has a known sister with an all female lineage, one would wish to get a sample from that lineage and compare her DNA to the others. Alternatives: the daughter of a man who didn't stay in the area long. An adopted child. A cousin. The widow of an underage man.

Sample Case 2.

A daughter of a known name "disappears" between Censuses. Records of marriages are sparse. There is no record whether she married or died. A candidate is presented. Her mtDNA can be compared to that of a known daughter. While mtDNA cannot PROVE a woman IS the daughter, it can eliminate candidates.



			USING mtDNA in GENEALOGY

mtDNA Passed from mother to children; however only daughters pass it on to their children Mutates much more slowly than Y-DNA Match on the high resolution test gives 50% probability that the MRCA is no more than 28 generations ago, or about 630 years ago

		CONTRAST to Y-DNA: Y-DNA: Donate a sample and wait for match with other sample donor(s) "Shotgun approach" -- fire two or more "shotguns" at a target and eventually a bead from one will hit a bead from another MUST be male donor (not adopted) descended from earliest known male ancestor. Same surname from oldest known ancestor to donor. mtDNA: Need to have specific women to test & some idea of the relationship between them. "Darts Approach" Known woman is the bull's eye. Specific samples are aimed at a match with her. Donor can be male or female

		Sample Case 1 Between 1800 and 1830 five girls marry in a certain county. During that period only three men with the same surname are present in the county that could possibly be the fathers of these women. Unless the men's wives are all sisters, the daughters of each couple will have different mtDNA. There is one known daughter of one man who has an alll female lineage to a descendant who is willing to donate a sample of mtDNA. There are all female lines of descent for the other women, but nobody knows which woman belongs to which couple. Obtain a sample from the KNOWN daughter of Couple #1. We now have the mtDNA "signature" of the wife in Couple 1. Obtain samples from the descendants of the other women. Compare them to the KNOWN daughter. The 2 girls who match the known daughter should be her sisters . The other 3 girls who do match the known daughter, nor do they match each other. We also now know 1. These girls are not sisters to the KNOWN daughter, nor to each other. 2. There is one more unaccounted for set of parents. The most obvious explanation, of course, although it is not necessarily the case, is that one the girls was a sister of one of the men. If any of the men has a known sister with an all female lineage, one would wish to get a sample from that lineage and compare her DNA to the others. Alternatives: the daughter of a man who didn't stay in the area long. An adopted child. A cousin. The widow of an underage man.

	Sample Case 2. A daughter of a known name "disappears" between Censuses. Records of marriages are sparse. There is no record whether she married or died. A candidate is presented. Her mtDNA can be compared to that of a known daughter. While mtDNA cannot PROVE a woman IS the daughter, it can eliminate candidates.