Journal Club - Genetic Ancestry and Natural Selection Drive Population Differences in Immune Responses to Pathogens

Post date: Nov 30, 2016 7:20:24 AM

Today's Journal Club paper was "Genetic Ancestry and Natural Selection Drive Population Differences in Immune Responses to Pathogens." The authors measure gene expression in macrophages derived from 171 American individuals of varying African ancestry, before and after challenging the cells with Salmonella or Listeria infection. Interestingly, the authors see that cells with greater African ancestry are more successful at clearing infection, and also have higher expression of immune-related genes. At least some of the effect of gene expression is mediated through local DNA polymorphisms. It would be a nice demonstration of directional selection if the variants that cause higher expression were found to be at higher frequency in the African-American population, much like Allen Orr's sign test.