DNA Clues to Our Kind: Regulatory gene linked to human evolution

A gene that exerts wide-ranging effects on the brain works harder in people than it does in chimpanzees and other nonhuman primates, a DNA disparity that apparently contributed to the evolution of Homo sapiens, according to a new study.

The gene participates in production of prodynorphin, an opiumlike protein that serves as a building block for chemical messengers in the brain known as endorphins.