Does genetic diversity predict health in humans?

Area of Science:

• Human genetics
• Evolutionary biology
• Immunogenetics

Background:

• Genetic diversity, particularly within the Major Histocompatibility Complex (MHC), is linked to disease resistance and fitness in many species.
• Recent studies suggest a connection between genetic diversity and human mate preferences.
• The adaptive significance of these preferences in relation to health outcomes remains largely unexplored.

Purpose of the Study:

• To investigate if genetic diversity at Major Histocompatibility Complex (MHC) and non-MHC loci predicts health status in humans.
• To determine if genetic diversity influences the likelihood of experiencing fewer health symptoms.

Main Methods:

• Assessed genetic diversity using heterozygosity and standardized mean d(2) at MHC and non-MHC microsatellite loci in 153 individuals.
• Correlated genetic diversity measures with self-reported health symptoms over a four-month period.

Main Results:

• Higher allelic diversity (d(2)) at non-MHC loci and one specific MHC locus (linked to HLA-DRB1) was associated with fewer reported health symptoms.
• No significant association was found between heterozygosity (at MHC or non-MHC loci) and health outcomes.
• Previous findings indicate non-MHC d(2) influences male preference for female faces.

Conclusions:

• Non-MHC genetic diversity, specifically allelic diversity (d(2)), may play a role in natural selection by predicting health status.
• This diversity may also be significant in sexual selection, potentially influencing mate choice based on health indicators.
• The findings suggest a dual role for non-MHC genetic diversity in human evolutionary processes.