This is likely explained by the fact that CKD manifests at anolder age, when the reproductive period of the individual has already passed,exerting no significant natural selection disadvantage.47 Both variants have an unusual combination of high prevalenceand strong effect, resultant of selective pressure related to innate immunity.54 The APOL1 variants are anunusual example where the mutation in a single gene is associated with increasedrisk of a complex disease.24 The gene discussed is APOL1; the disease is chronic kidney disease.