Major Histocompatibility Complex genes, symmetry and body scent attractiveness in men and women
Thornhill, R., Gangstead, S. W., Miller, R. D., Scheyd, G., McCollough, J. K., and Franklin, M.
Abstract:
Previous research indicates that the scent of developmental stabilitylow fluctuat-ing asymmetry (FA)is attractive to women who are fertile (at high-conception risk points in their menstrual cycles), but not to other women or men. Prior research also indicates that the scent of dissimilarity in major histocompatibility complex (MHC) genes may play a role in human mate choice. We studied the scent attractiveness to the opposite sex of t-shirts worn for two nightsı sleep. Our results indicate that the two olfactory systems are independent. We repeated previous results from studies of the scent of symmetry. We repeated previous results from MHC research in part; men, but not women, showed a preference for t-shirts with the scent of MHC dissimilarity. Womenıs scent ratings of t-shirts were uncorrelated with the wearerıs MHC dissimilarity and allele frequency, but positively correlated with the wearerıs MHC heterozygosity. Fertile women did not exhibit any MHC trait preferences. Womenıs preference for the scent of men who were hetero-zy-gous for MHC alleles may be stronger in women who are at infertile cycle points. Men preferred the scent of common MHC alleles, which may function to avoid mates with rare alleles that exhibit gestational drive. Men also preferred the scent of women at fertile cycle points. The scent of facially attractive women, but not men, was preferred. Neither FA nor facial attractiveness in either sex correlated with MHC dissimilarity to others, MHC heterozygosity or MHC allelic rarity.