Thursday, September 01, 2005

Chimpanzee Genome Mapped

Scientists have complete genetic maps of humans, mice, and rats, and now they one for chimpanzees, our closest relatives.

Their genome is 3 billion base pairs long. There are 40 million differences from humans. 35 million small variations (believed to be tiny random mutations) and 5 million larger differences. While that's a 4% difference from humans, it's believed 3/4 of the diffs are in junk DNA so we're only 1% different. In looking at the different genes, some have been postualated to be involved in brain development and some for language, which would match up nicely to the real differences between us. But the biggest diffs they've found are in how the genes are regulated.

I didn't realized this: "Chimpanzees have repeatedly toppled conceptions about the ways in which humans are purportedly unique. They fashion and use tools, including hammers, anvils, probes for fishing termites from the ground and seats to rest on, though unlike humans, they make all their tools by modifying found objects and never by putting complementary pieces together. Chimps also medicate themselves, swallowing rough leaves and chewing on bitter stems to treat a type of intestinal infection. And in perhaps their cheekiest aping of humanity, chimpanzees display remarkable political acumen. They form complex alliances and trade grooming services, sex and food. Like many denizens of the world's great cities, they lobby, demand bribes, repay favors and, when crossed, extract revenge."

Apparently the differences also match some mathematical corollaries of the theory of evolution. "I can't imagine Darwin hoping for a stronger confirmation of his ideas," said Robert H. Waterston, who led the Washington University team. As Opus would say: "PPHPHPT!"

1 comment:

Anonymous said...

The term "junk DNA" used in the reference article is misleading, although much of the genome probably is junk. As more organisms are sequenced, we are discovering that significant sections of non-coding DNA (that is, DNA that doesn't code for proteins) is conserved among species, suggesting it has some function.

If interested, see:

http://www.genome.gov/11007524