Epigenetic differences between chimps and humans
Soojin Yi and her colleagues at Georgia Tech may have found an explanation for why humans are so different from chimps, even though we share 96 per cent of our DNA with our furry friends. Publishing in the American Journal of Human Genetics, the researchers studied samples of brain tissue from both species, looking at levels of DNA methylation - an epigenetic mark that can switch genes off. They found hundreds of places where methylation levels were significantly lower in humans than in chimps, with an unusually high proportion in genes related to diseases such as autism, alcoholism and other addictions and even cancer.
Intriguingly, chimps have a lower risk of cancer than humans, something the researchers think may be linked to the difference in methylation. Although it's still early days for this research and a lot more work needs to be done to show how significant these differences are, the findings hint that epigenetic differences arising during evolution could have implications for a range of human diseases.