Men's preferences for women's body odours are not associated with human leucocyte antigen

Abstract

Body odours reportedly portray information about an individual's genotype at the major histocompatibility complex (MHC, called human leucocyte antigen, HLA, in humans). While there is strong experimental support for MHC-associated mating behaviour in animals, the situation in humans is more complex. A lot of effort has been spent on testing HLA-associated odour preferences of women. To date, only very few studies have looked at HLA-linked olfactory preferences in men and these studies have revealed inconsistent results. Here, we investigate men's HLA-associated preferences for women's body odours. Importantly, and in contrast to previous studies, these odours were gathered at peak fertility (i.e. just before ovulation) when any HLA-associated odour preferences should be strongest. We scrutinized whether men's preference for women's body odours is influenced by (i) the number of shared HLA alleles between men and women, (ii) HLA heterozygosity, and (iii) the frequency of rare HLA alleles. We found that men could readily differentiate between odours they found attractive and odours they found less attractive, but that these preferences were not associated with HLA. Specifically, men did not prefer odours from women who are HLA dissimilar, HLA heterozygous, or who have rare HLA alleles. Together, these findings suggest that HLA has no effect on men's odour preferences.

The scent of attractiveness: levels of reproductive hormones explain individual differences in women's body odour

“…The pads were thawed three hours before the respective rating session started and were placed in separate 500 ml opaque glass jars (cf. [1,41,42]). Three research assistants smelled the pads and confirmed that none was contaminated with extraneous odours (e.g.…”

“…To assess the odour preferences we closely followed the procedures reported in [1,41]. To prepare for the rating session, odour raters (all male) were asked not to eat and to refrain from drinking caffeinated or alcoholic beverages for one hour before testing, as these activities are known to affect smelling ability.…”

Accumulating evidence suggests that men do not find body odours of human leucocyte antigen-dissimilar women more attractive

“…In our recent study published in Proceedings of the Royal Society B [1], we investigated the effects of major histocompatibility complex (MHC; or human leucocyte antigen system, HLA in humans) on men's preferences for women's body odours. Using rigorous methods, we found no evidence that men find body odours of HLA-dissimilar women more attractive than odours of HLAsimilar women.…”

“…So, it is conceivable that men rely less on HLA-mediated odour cues when choosing their mates than women. We note that apart from our study [1], only four studies have included men as odour raters. Two of these studies report no preference HLA-dissimilar women [13,14], and two suggest that men show a preference for body odours of HLAdissimilar women [6,15] (note that Wedekind & Furi included odours of only two women).…”

“…So, if not controlling for menstrual cycle, cyclic effects of odour attractiveness are likely to overwrite any putative HLA-effects. In our recent study [1], we controlled for menstrual cycle phase. We also included a large number of female odour donors (n ¼ 49) and collected ratings of 94 men.…”