Wednesday, August 31, 2005

Well I'll be a Monkey's Niece !


Scientists released several studies today comparing the genetic coding for humans and chimpanzees. The studies stated that 96 percent of our DNA sequences are identical. The other 4 percent appears to contain clues to how we became different from our closest relatives in the animal kingdom, they said. These were several key points of the study were:

•Small but crucial differences: The researchers said the results confirmed the common evolutionary origin of humans and chimpanzees. Out of the 3 billion base pairs in the DNA coding for chimps and humans, about 35 million show single-base differences, and another 5 million DNA sites are different because of insertions or deletions of genetic code. Waterston estimated that 1 million of those coding changes are responsible for the functional differences between humans and chimps — thus defining our humanness.

•Six new genetic frontiers: Scientists identified six regions of our DNA that appear to have evolved dramatically over the past 250,000 years — including a "gene desert" that may play a role in nervous system development and also has been linked to obesity. They said a seventh region that showed notable change contains the FOXP2 gene, which already has been linked to speech in humans.

•Brain genes key: A comparison of gene expression in various tissues indicated that most of the genetic changes occurring during the evolution of chimps and humans had neither a positive nor a negative effect. However, the testes in the males of both species showed strong evidence of a positive effect. Also, genes active in the brain showed much more accumulated change in humans than in chimps — suggesting that those genes played a special role in human evolution.

•Primates' risky business: Scientists compared the chimp and human genomes with those of mice and rats, and found that both primates carried a greater amount of potentially harmful genetic coding. They speculated that such coding may have made primates more prone to genetic diseases, but also more adaptable to environmental changes.

•Clues to diseases: The genomes contained hints that the chimpanzee genetic code has been attacked more frequently than humans by retroviral elements — such as those present in the HIV virus. Scientists also noted key differences between the genomes that may affect susceptibility to viruses, the workings of the immune system and the progression of diabetes and Alzheimer's disease in humans.

I wonder how the intelligent design people are going to feel about this? Hmmmmm got evolution?



Posted by @ 5:38 PM
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