Identifying population differences in genes that affect body mass index

Genomic regions of interest can be narrowed by studying populations that have patterns of low linkage disequilibrium. A recent study of body mass index in African Americans demonstrated this point and, through cross-population analyses, revealed additional genomic associations. This comparative analysis showed how rare alleles that associate with traits in specific populations can be detected in cohorts where the same alleles are not rare, and highlights how population diversity can aid genetic analyses.