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(Ivanhoe Newswire) – It’s generally assumed that humans are becoming more alike, but a new study uses genomic technology and shows human evolution is actually speeding up. So, are we becoming more different?

“Our study denies the widely held assumption or belief that modern humans (those who widely adopted advanced tools and art) appeared 40,000 years ago, have not changed since and that we are all pretty much the same. We show that humans are changing relatively rapidly on a scale of centuries to millennia, and that these changes are different in different continental groups,” says Henry Harpending, professor of anthropology at the University of Utah.

For the study, researchers looked for genetic evidence of natural selection which is the evolution of favorable gene mutations during the past 80,000 years. They analyzed DNA from 270 individuals in the International HapMap Projects. They looked at what’s called SNPs which are single nucleotide polymorphisms. The SNPs is what are different between people in their DNA based pairs. The data included 3.9 million SNPs from 270 people in four different populations.

Over time, chromosomes randomly break and recombine to create new versions or variants of the chromosome. Researchers used that to see if the same chromosome from numerous people had a segment with an identical pattern of SNPs, then that means the chromosome has not broken up. Researcher say then they know the gene evolved recently, because if it had evolved a long time ago it would have broken up.

Using a computer, study authors say they found 7 percent of human genes are undergoing rapid, recent evolution. They also found a lot more diversity in the SNPs than expected. Study authors also point out that the increase of human population from millions to billions in the last 10,000 years accelerated the rate of evolution because there are new environments to which humans need to adapt.

SOURCE: Published online in the journal, Proceedings of the National Academy of Sciences on Dec. 10, 2007

This entry was posted on Wednesday, December 12th, 2007 at 12:12 pm and is filed under Medical News. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.