A new comparison of chimpanzee and human genomes has offered an early but tantalizing look into what makes the two species, nearly identical at the DNA level, so different.
Scientists found key differences in areas linked to cell differentiation and immune response — and that could be just the beginning.
"By looking at all the variations, we will get a catalog, and when we find a variation in a person with a disease, it will help us understand the function of that variation," said study co-author Richard Redon, a geneticist at the Wellcome Trust Sanger Institute. "It will help us understand better how our species emerged."
Researchers already know that humans and chimpanzees share about 98 percent of the same genes. But rather than searching for mutations, Redon's team looked at a relatively unstudied phenomenon known as copy number variation, or CNV, in which genes are redundantly duplicated.
These variations were ignored in the early days of genetics, but have recently been recognized as important: Mutations are more likely to accumulate in a given type of gene when multiple copies exist, and the simultaneous application of multiple genes can provide a functional boost.