Evaluation of polymorphisms known to contribute to risk for diabetes in African and African-American populations

Purpose of review Populations of direct African ancestry have much greater genetic diversity than do other populations. African-American populations exhibit twice the prevalence of type 2 diabetes as compared with their Caucasian counterparts. African-American populations are likely to have unique genetic susceptibility to type 2 diabetes. This review addresses current knowledge of susceptibility genes that are shared with other groups and those that are unique to populations of African descent. Recent findings When compared with the plethora of Caucasian studies, relatively few studies have been conducted in African or African-American populations. The most exciting findings have been family-based linkage studies, which point to multiple regions that may harbor susceptibility genes. Recent work suggests that the major Caucasian locus, TCF7L2, plays a role in some African-based populations, whereas unique facors remain to be confirmed. Summary Although progress has been made in finding the genetic cause of type 2 diabetes in African and African-American populations, at this time no variant can be considered unequivocally confirmed as a diabetes susceptibility locus.