[bayourod]

Well isn't there something only passed from mom to daughter? I seem to remember some documentary about that being the way they trace migrations of races.

[SendShaqtoIraq]

"Well isn't there something only passed from mom to daughter?"

Common sense.

[PurVirgo]

yes, they have used mitochondrial DNA to trace race migration.

It's an extremely fascinating field of microbiology.

[Ichneumon]

Well isn't there something only passed from mom to daughter? I seem to remember some documentary about that being the way they trace migrations of races.

Well, you're almost there. Mitochondrial DNA is used to trace human migrations, but not exactly because it's "only passed from mom to daughter". It's passed from mom to daughter and/or son but it's *entirely* from the mother, none is contributed by the father.

So you sort of have it backwards -- it's not that it's passed only to daughters (it's not); the key point is that it's inherited only from mothers. So it's a lot easier to find undisturbed ancestral DNA markers from your mother's mother's mother's [...] mother, than it is to do similar traces with cellular DNA (because that keeps getting mixed and reshuffled every generation with 50/50 contributions from both maternal and paternal lines).

[BabsC]

The mitochondria DNA is only passed by the mother to her offspring. The mitochondria from the sperm is the propellant and is not absorbed into the ovum. The family line can be genetically traced more thoroughly through the female line not the male line.