Dr. Rotimi's research focuses on the etiology of complex diseases and health disparities. His team studies interethnic differences in the distribution of genetic and environmental risk factors, with particular emphasis on populations of African ancestry.

The Africa America Diabetes Mellitus (AADM) study, developed under Dr. Rotimi's leadership, has enrolled over 6,500 related and unrelated type-2 diabetes (T2D) cases and ethnically matched controls from West (Nigeria and Ghana) and East (Kenya) Africa. Using this resource, his lab published the first genome-wide scan for T2D in Africans. In collaboration with deCODE Genetics, susceptibility loci for T2D were identified in three genes (TCF7L2, CDKAL1, and TCF2 [HNF1β]). Notably, the West African cohort has been useful for refining the association signals found in European and Asian ancestry populations; it has provided some of the earliest evidence for how relatively diverse populations might facilitate fine-mapping of loci originally identified in more homogeneous populations characterized by larger regions of strong linkage disequilibrium. CRGGH continues to use genomic data generated in African populations to refine and fine-map loci identified in European and Asian populations for multiple traits including glucose, uric acid, bilirubin, CRP and serum lipids.