More than skin deep: Major histocompatibility complex (MHC)-based attraction among Asian American speed-daters

Facial attractiveness is only weakly linked to genome-wide heterozygosity

Introduction

It has been frequently suggested that overall genomic heterozygosity and, particularly, heterozygosity of loci on the so-called major histocompatibility complex (MHC), which is responsible for the recognition of foreign substances/ pathogens and the recognition of self and non-self, is associated with better health and better resistance to infections and parasites. It has further been speculated that such a potentially beneficial heterozygosity can be detected through body odor and facial attractiveness.

Methods

On the basis of genome wide SNP data (713,014 SNPs) of participants from the Wisconsin Longitudinal Study, we therefore investigated whether homozygosity either on the MHC (measured as inbreeding coefficient) or genome-wide (measured as runs of homozygosity and inbreeding coefficient) is associated with rated facial attractiveness.

Results

Although we found that the genome-wide average length of homozygous segments and the genome-wide inbreeding coefficient are significantly negatively associated with some measures of facial attractiveness, if corrected for multiple testing, any significant association was no longer formally significant after correction. In addition, the variance in facial attractiveness explained by the genome wide homozygosity is very low (<0.15%). We did not find any significant association between the inbreeding coefficient on the MHC and facial attractiveness.

Discussion

We only find a weak association of genome- wide heterozygosity and facial attractiveness.

Handsome or Rugged? : A Speed-Dating Study of Ovulatory Shifts in Women's Preferences for Masculinity in Men

We tested the good genes ovulatory shift hypothesis through speed-dating, an ecologically valid paradigm with real life consequences. Fifteen speed-dating sessions of 262 single Asian Americans were held. We analyzed 850 speed-dates involving 132 men and 100 normally ovulating women, finding ovulatory shifts in the desirability of men with more masculine facial measurements (smaller eye-mouth-eye angle, larger lower face to full face height ratio, and smaller facial width to lower face height ratio) in the predicted direction. However, there was no support for ovulatory shifts in preferences for men's self-reported height. In addition, the expected shifts were not found for women's second date offers to men. Therefore, with natural stimuli and in a competitive dating scenario, we partially replicated previously documented ovulatory shifts in women's preferences for men.

No evidence for a relationship between MHC heterozygosity and life history strategy in a sample of North American undergraduates

Although allelic diversity at the major histocompatibility complex (MHC) has implications for adaptive immunity, mate choice, and social signalling, how diversity at the MHC influences the calibration of life history strategies remains largely uninvestigated. The current study investigated whether greater MHC heterozygosity was associated with markers of slower life history strategies in a sample of 789 North American undergraduates. Contrary to preregistered predictions and to previously published findings, MHC heterozygosity was not related to any of the psychological life history-relevant variables measured (including short- vs. long-term sexual strategy, temporal discounting, the Arizona life history battery, past and current health, disgust sensitivity, and Big Five personality traits). Further, no meaningful effects emerged when analysing women and men separately. Possible reasons for why the current results are inconsistent with previous work are discussed.

'Our life is pointless … ': Exploring discrimination, violence and mental health challenges among sexual and gender minorities from Brazil

Worldwide, Brazil has the highest prevalence of violence and hate crimes against sexual and gender minorities (SGMs) among countries with available data. To explore the impact of this scenario, we conducted a qualitative study with 50 SGMs from Rio de Janeiro, Brazil. Among the participants, 66% screened positive for generalised anxiety disorder, 46% for major depressive disorder and 39% for PTSD. A third reported low self-esteem (32%) and one quarter low social support (26%). Experiences of interpersonal discrimination were highly prevalent (>60%), while institutional discrimination related to employment or healthcare was reported by 46% of participants. Verbal abuse is very common (80%), followed by physical assault (40%). Sexual violence is highly frequent among women. Focus groups analysis highlighted three major domains: (1) stigma and discrimination (family, friends and partners, in schools and health services, influencing social isolation); (2) violence (bullying, harassment, physical and sexual violence); and (3) mental suffering (alcohol and drug abuse, depression, suicidality, anxiety). Our findings suggest a close synergy between experiences of discrimination and violence with selected mental disorders. This complex synergy might be better addressed by longer-term individual and group-level interventions that could foster social solidarity among the different groups that comprise SGMs.