They Are Here
Last summer my friend Phil was visiting me from California. I don't see him nearly often enough. We entertain each other way too much.
So, anyway, we were walking around my neighborhood one day and I commented that I thought a race of superhuman beings was slowly infiltrating us, gradually taking over the world. As evidence, I pointed out all the remarkably tall people walking past us. As we moved through the neighborhood, we began surreptitiously pointing them out to each other. "Look, there's one." A slight nudge to the ribs, a nod in a particular direction, knowing looks exchanged.
It turns out we may have been right. Well, maybe not about the tall people. But I feel certain They truly are among us. They're just being very quiet about it.
There is an article in pre-press now -- coming out in the February issue of Nature Genetics -- by scientists at deCODE Genetics of Reykjavik who (while searching for a gene that might cause or contribute to schizophrenia) discovered a region in the human genome that may give fertility and longevity boosts to some 20% of the European population.
Are we beyond the forces of evolution, or is natural selection still shaping us? A genomic study of modern Icelanders suggests modern humans are still a work in progress.
The finding comes from deCODE Genetics, a company based in Reykjavik, Iceland that is hunting for disease-associated genes. While analyzing DNA sequence from more than 29,000 Icelandic people, deCODE researchers discovered something intriguing. A section of chromosome 17, 900,000 base pairs long, is flipped into reverse order in about 20% of Europeans, but this flip is very rare among Africans and Asians. Inversions on a smaller scale happen frequently when chromosomes reshuffle themselves in the course of sexual reproduction. Usually, they flip back with the same frequency. Also striking was the fact that the two versions of the chromosomal section appear to have been around for some 3 million years, long before the appearance of modern Homo sapiens.
The fact that such an extended stretch of inverted DNA appears to have been maintained for so long and today is carried by 1 in 5 Europeans suggested that it must provide some kind of evolutionary advantage in the European environment. If natural selection played no role, one of the two versions would have likely dropped to a low frequency long ago.
[T]he DeCode researchers found that women carrying the flipped or inverted section tend to have slightly more children.
The chromosome 17 inversion... occurs at much higher frequency in women over 95 and in men over 90 than in the normal population. "It seems to confer on people the ability to live to extreme old age," Stefansson said.
Well, no use complaining, I guess. Whining didn't help the Neanderthals. I suppose the upside is we do still seem to be evolving in spite of improved health care, better education, and central air-conditioning ("better" as in "better than when we were confined to the prehistoric plains of the Serengeti", I mean). Who knows? Maybe we'll eventually evolve a brain.
And if Tall People really are here, that's okay too, I guess. More leg-room for shrimps like me. There's always a bright side even as your blossom on the Tree of Life turns brown.