Redhead Genomics: Immune Perks But Gluten-Linked Health Tradeoffs

Harvard Medical School researchers analyzed 10,000 years of DNA from about 16,000 people and found that the genetic variants behind red hair and fair skin were favored by natural selection, with potential immune benefits (including HIV resistance and leprosy resistance) and lower risk of certain conditions, but these same genes may raise the risk of gluten-related autoimmune diseases such as Crohn’s disease and celiac disease, possibly linked to the advent of wheat farming; vitamin D production advantages were noted in earlier work.