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 factors 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.