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07/31/2007: "Genetics reveals humans radically different from chimps"
As Sikela and co-workers explain in a paper published online 31 July in Genome Research, they compared the DNA from more than 24,000 known human genes to the DNA from chimpanzees, gorillas, bonobos, orangutans, gibbons, macaques, baboons, lemurs, and marmosets. Applying CGH, researchers take one stretch of DNA as a target--in this case, each human gene--and then check which complementary strands of DNA will stick to it. "We don't think anyone has looked this comprehensively at gene gain and loss over time," says Sikela.
All told, the researchers found more than 4000 genes that showed lineage-specific changes in copy number, with the numbers steadily increasing over evolutionary time. Humans, for example, only had 84
genes with increased copy numbers over those of our closet relatives. In contrast, lemurs, which have evolved for 60 million years, have 1180 genes with extra copies. "This is further evidence that genomic
differences between humans and other primates is far, far more complex than we originally imagined they might be," says Ajit Varki, who studies human/chimpanzee differences at the University of California, San Diego. "However, many of the differences may or may not be relevant for explaining 'humanness.'"
[ It's good we found hard science for explaining the obvious. Next we'll find out that differences between races, and then ethnic groups within them, are bigger than we've been told. The scientists who rarely get headlines are the ones who labor for truth, but the ones who get big financial reward are those who take a popular attitude and edit science to support it. Dishonest, but so is this time. ]
http://sciencenow.sciencemag.org/cgi/content/full/2007/730/4