Monday, March 23, 2009


This is the codename of the point-mutation, in my mitochondrial DNA, which signals that I belong to the maternal haplogroup (or matrilineal line) known as H7. It means that, at the 4793rd position in my mitochondrial DNA (hightlighted in purple on the image below), instead of having a letter A (the DNA base, or building block, called adenine), my sequence contains another base, namely a guanine (or G). But that’s not the only ancestry-defining point-mutation which is present in my mitochondrial DNA, for it obviously also contains the series of mutations that accumulated, generation after generation, in my maternal ancestors’ genes since the so-called mitochondrial Eve (the mother of all modern human beings, who, experts agree, lived in Africa around 200,000 years ago) walked on this planet.

At 23andme, they tell me that the sequence of the point-mutations which, starting with A4793G (4793 for short) and travelling back in time, go from haplogroup H7 back to mitochondrial Eve, is as follows: 4793, 2706, 7028, 11719, 12705, 10398, 10873, 15301, 8701, 9540, 1018, 769, 13650, 16278, 3594, 4104, 7256, 7521, 10810, 15301, 16129, 16187, 16189, 825, 8655, 2758, 2885, 7146, 8468, 16230, 11914, 10589, 6185, 4312. (A soupful of numbers indeed!) Mutations at positions 2706 and 7028, for instance, define haplogroup H, of which H7 is a direct sub-haplogroup. Thus, going down the tree from the branches to the trunk, one goes through a series of increasingly ancient haplogroups: HV, R, N, L3, L2, L1, and on back to that single, primordial mother.

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