Not Egyptian

Photo of me by Wesley Abney
Photo of me by Wesley Abney

At a party last night, a woman asked where I am from. I told her my hometown. She said, “No, no, no, where are your parents from.” I thought, “Oh, boy, I know where this is going.” So I told her my father is black and my mother white. She wanted to know what part of Africa he is from. I told her my father’s first cousin got the mitochondrial DNA tested and it was from Ghana, but both mDNA goes mother to child so his relationship to this cousin is through his father makes and in the amount of time since they probably left Africa, that would be one of a 128 to1024 ancestors [1] so not really relevant. She dismissed the latter part and said I really look Egyptian (as her husband is Egyptian). She says a number of Ghanaians have immigrated to Egypt. I must have had a weird look on my face because she said at that point if she was boring me we did not have to talk about it. Her main point is I look a lot like her husband. Enough for her to think I was Egyptian.

Since I look enough like any number of relatively brown skinned people from all over the world and sport a scarily bushy beard, some people make interesting first impressions about my background. I have heard Greek, Saudi, Persian, Indian, and other Middle Eastern. Egyptian fits nicely. Still not Egyptian.

Though I am amused.

1: The move out of Africa was probably 7 to 10 generations back.

Find Wesley Abney who took this photo on Flickr.

DNA For Everyone

So, 60 Minutes has broadcast a report on the tracing of DNA. Leslie made a statement, “The are just two bits of DNA which remain pure. The Y chromosome which passes directly from father to son. And something called mitochondrial DNA which passes unchanged from mother to child.” Logically speaking, if the mDNA really passes unchanged with every generation, then everyone has the exact same mDNA. However, that is not the case. A limited number of aberrations have occurred in the mDNA over time. Those changes are called markers and passed from mother to child. Identification of these markers and estimating when and which groups they occurred is the process behind identifying to whom an individual is related.

Leslie did make a really good point. As you trace back through the Y chromosome and mDNA, the further back one goes, the smaller the ratio of these markers can provide. So going back one generation, you can see info on both individuals. Going back to the second generation, you can only see 2 of 4 individuals, three see 2 of 8, eight see 2 of 256, etc.

Another fuzziness the report failed to explain is the testing really only matches individuals to currently living individuals who share similar markers. So, you don’t really see who your ancestors are. An African-American woman showcased, got back several matches to individuals belonging to tribes in Sierra Leone, Ivory Coast, and Senegal. I have first and second cousins all over the place. Is it right to assume only individuals taken from Africa and brought to the Americas are the ones who have left the tribe? It seems hard to believe family members left in Africa occupy the same huts as when we left.

A good book to read on Y chromosome and mDNA tracing to determine the origins of all the world’s population to common ancestors in Africa is The Journey of Man by Spencer Wells. That is a little further back.