Examining the evidence for major histocompatibility complex-dependent mate selection in humans and nonhuman primates

Abstract

Compounds of the major histocompatibility complex (MHC) are integral for effective vertebrate adaptive immune response, and are also implicated as cues for sexual selection. The evidence for this is supportive of MHC-based preference for diverse and dissimilar mating partners, in a range of vertebrates from fish to nonhuman primates. However, the evidence for a similar role of these genes and the evolutionary benefits of their diversity in human mate choice has been more controversial. Here, we review the results of 34 primary studies on MHC-mediated mate choice in humans and nonhuman primates in an effort to understand what processes may underscore, or belie, such differences. Both human and nonhuman primate studies show evidence of mate selection for MHC-dissimilarity and diversity, with fewer results in support of mate selection for optimal diversity or for specific "good gene". In general, stronger support comes from female-choice studies as opposed to male-choice studies (though male preferences and choice are investigated less often). This review suggests that the majority of mate choice results from contemporary human studies are consistent with our evolutionary history, but also reveals that only in humans do we find evidence for preference for mates with similar MHC composition. Overall, we show that contextual nuances, namely, population structure, multiple sensory cues that signal different information, and hormonal influences may explain the conflicting results observed for the role of MHC in human sexual preference, and argue for the exploration of such caveats in less well-studied systems to discern between general patterns and qualities unique to humans.

Patterns ofMHC‐dependent mate selection in humans and nonhuman primates: a meta‐analysis

“…Another methodological source of heterogeneity we tested was choice cue because preferences based on different stimuli could show different patterns, but we found no strong evidence of this and other studies have found positive correlation between facial and scent attractiveness (Thornhill & Gangestad 1999;Thornhill et al 2003). Additional methodological differences between human studies and their implications for results have been thoroughly discussed elsewhere (Wedekind et al 2002;Havlicek & Roberts 2009;Derti et al 2010;Winternitz & Abbate 2015). We note that we cannot unanimously differentiate whether the differences between study outcomes are caused by methodology or biology, and it is likely that both types of mechanisms are in effect.…”

“…; Havlicek & Roberts ; Derti et al . ; Winternitz & Abbate ). We note that we cannot unanimously differentiate whether the differences between study outcomes are caused by methodology or biology, and it is likely that both types of mechanisms are in effect.…”

“…Data set compilation methods are described in detail in Winternitz & Abbate (). Briefly, studies were compiled from the reviews by Havlicek & Roberts () and Setchell & Huchard (), from the meta‐analysis by Kamiya et al .…”

“…Data set compilation methods are described in detail in Winternitz & Abbate (2015). Briefly, studies were compiled from the reviews by Havlicek & Roberts (2009) and Setchell & Huchard (2010), from the meta-analysis by Kamiya et al (2014), and additional studies were identified up from 2009 to January 2015 via Web of Science using the topic 'MHC' and 'Major Histocompatibility Complex' and 'mate choice' or 'mate selection' or 'mate preference' and searching within results for 'human' and 'primate'.…”

“…Lastly, it may sometimes be difficult to standardize experimental designs between studies when using human subjects and these methodological differences can also confound results (Havlicek & Roberts 2009). Several recent reviews have discussed these issues in attempts to reconcile significant and nonsignificant results from over three decades of human MHC mate choice research (Havlicek & Roberts 2009;Winternitz & Abbate 2015). However, only quantitative assessment that explores the magnitude and precision of effects can reveal the ultimate biological importance of phenomena (Nakagawa & Cuthill 2007).…”