Balancing immunity: disease risk mutation can be beneficial.
An allelic variant of the autophagy gene ATG16L1 (T300A) is a genetic risk factor for Crohn's disease. However, over 50% of the global population carries at least one copy. Yao et al. have demonstrated a heterozygote advantage, where the pathogen-protective effect of one allele may outweigh the disease risk in homozygotes.
Humans↗