It is a shame to see such a lovely piece of research blown away by their own shoddy practice. Mitochondrial DNA is a good way to tell how closely related segments of the population are. In this case they have been "mining" mDNA of blue eyed people with no regard to whether the mDNA (which must by definition come from the mother) has come from a blue eyed parent.

This is the equivalent of drawing conclusions about lemons from studying a bowl of mixed citrus. (Sit down citrus, not you.)

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