Inbreeding shaped the course of human evolution

[Judi Lynn]

Inbreeding shaped the course of human evolution
28 November 2013 by Michael Marshall

TALK about an inauspicious beginning. For thousands of years our ancestors lived in small, isolated populations, leaving them severely inbred, according to a new genetic analysis. The inbreeding may have caused a host of health problems, and it is likely that small populations were a barrier to the development of complex technologies.

In recent years, geneticists have read the genomes of long-dead humans and extinct relatives like Neanderthals. David Reich of Harvard Medical School in Boston has now sequenced the Neanderthal genome and that of another extinct human, the Denisovan, to an unprecedented degree of accuracy. He presented his findings at a Royal Society meeting on ancient DNA in London on 18 November.

Describing the genomes as "nearly error-free", Reich says both species were severely inbred due to small populations. "Archaic populations had low genetic diversity, really extraordinarily low," he said. "It's among the lowest diversity of any organism in the animal kingdom."

One Neanderthal, whose DNA Reich obtained from a toe bone, had almost no diversity in about one-eighth of the genome: both copies of each gene were identical. That suggests the individual's parents were half-siblings.

More:
http://www.newscientist.com/article/mg22029453.500-inbreeding-shaped-the-course-of-human-evolution.html?cmpid=RSS|NSNS|2012-GLOBAL|online-news#.UpruAurnb_R

[kickysnana]

1. One toe bone does not a sociology of a species make.