Multiple common risk alleles have been identified as reproducibly associated with risk of type 2 diabetes (T2D) [1]–[13]. With the exception of the KCNQ1 locus which was identified in the Japanese population [1], [2], all of the well-replicated risk variants were first identified in populations of Northern European ancestry [3]–[13]. T2D morbidity varies widely across racial/ethnic groups; the prevalence is more than twice as high among African Americans, Japanese Americans, Latinos and Native Hawaiians as European Americans [14], [15]. It is important to evaluate whether and how genetic variation may contribute to health disparities between populations. For example, genetic variation at 8q24 may contribute to population differences in risk of prostate cancer [16], [17], and genetic variation at MYH9 contributes substantially to the higher rates of kidney disease in African Americans [18].
