Smelly T-shirts

Individuals' ability to distinguish different smells may reside in their distinct genetic make-up. In the February issue of Nature Genetics, Suma Jacob and researchers at the University of Chicago report their studies of the genetic basis for smell preference (Nature Genetics 2002, 30:175-179). They studied personal odours associated with the major histocompatibility complex (MHC) locus, which have been linked to human behaviour. They chose 49 unmarried women from an isolated community with limited MHC haplotypes, took men of different cultural backgrounds, and presumably with different body odours (they were Jewish, Dutch, German, Polish, Scottish, Sikh or Spanish), and asked them to wear the same T-shirt on two consecutive nights. They then tested the odour choices of the women (who were unaware that they were smelling men's dirty T-shirts). They were asked to rank the smells according to familiarity, intensity, pleasantness and spiciness. The women consistently preferred smells from men with whom they shared the same MHC genes. Further analysis revealed that the MHC-associated odour choices were related to the paternally-inherited MHC allele.