Freshly brewed coffee, rancid meat, the scent of a mother, an alarming waft of smoke—good or bad, smell is a powerful sense, capable of rousing remote memories, guiding behaviors and influencing moods. Scientists have long suspected that the immense diversity in human olfactory experience results at least partly from heredity, and now a research team has shown that the perception of specific odors can indeed be traced to one’s genes. Beyond connecting the dots between genes and odors, these findings raise intriguing questions about human evolution. Our repertoire of functional olfactory genes has been shrinking over evolutionary time—and no one knows why.
Scientists at the Rockefeller University and Duke University have demonstrated that chemicals secreted in male sweat can smell like stale urine to one person, sweet flowers or vanilla to the next, or nothing at all to another, depending in part on which variant of an odorant receptor they have in their noses. The sweat chemicals investigated, androstenone and androstadienone, are particularly sexy odors because they are degradation products of the hormone testosterone.