September 19, 2007
- Molecular biology
Whether a man smells sweet or stinky is in the odorant receptor of the beholder
Genetic differences determine whether a component of male body odor smells like sweat, vanilla, or nothing at all, according to newly published research. The component is androstenone, a steroid derived from testosterone that is present in sweat.
To some people, androstenone smells pleasant, with a sweet, floral, or vanilla-like scent. Others find the compound's odor offensive and liken it to sweat or urine. A third group can't even smell the compound. The wide variability in people's perception of androstenone is due in large part to slight genetic variations that affect the odorant receptor OR7D4, report Leslie B. Vosshall, an associate professor who heads Rockefeller University's Laboratory of Neurogenetics & Behavior; Hiroaki Matsunami, an assistant professor of molecular genetics and microbiology at Duke University Medical Center; and their colleagues (Nature, DOI: 10.1038/nature06162).
The researchers determined that people who find androstenone unpleasant have two single-nucleotide polymorphisms in the gene for the receptor which is expressed in sensory cells in the nose. In vitro studies showed that these mutations severely impair the receptor's function.
Matsunami says the work represents the first demonstration of a link between the performance of a human odorant receptor and "how that odor is perceived.” He adds that "the sex-steroid odors that we tested in humans act as pheromones in pigs, and there has been debate whether these same chemicals act similarly in humans. There is evidence that smelling these odors can affect the mood and physiological state of both men and women.”