Chimps are not cancer prone unlike humans even though both share a genetic similarity. For that matter, chimps rarely develop cancer.
Georgia Tech's Soojin Yi, a biologist, looked at brain samples of the two species. She found that differences in the modification of certain DNA, called methylation, may contribute to such changes.
The results also hint that this process of DNA modification plays an important role in some disease-related phenotypes (composite of an organism's observable characteristics or traits) in humans, including cancer and autism, the American Journal of Human Genetics reports.
"Our study indicates that certain human diseases may have evolutionary epigenetic (the effect of environment on genes) origins. Such findings, in the long term, may help develop better therapeutic targets or means for some human diseases," says Yi, according to a Georgia Tech statement.
Yi and her team generated maps of modified DNA of the prefrontal cortex (front part of the brain, tied to personality, decision making and moderating social behaviour) of multiple humans and chimps. They found hundreds of genes (among humans) that "include disproportionately high numbers of those related to diseases," said Yi.
"They are linked to autism, neural tube (brain and spinal cord) birth-related defects and alcohol and other chemical dependencies," said Yi.