There are likely many factors contributing to underrepresentation of AA in genetic research. Within the general population, there are fewer AAs than EAs, making it more difficult to recruit the large numbers of individuals necessary for genetic research. Ancestral diversity significantly complicates genetic analyses,51 providing impetus for scientists to maintain genetic homogeneity in their studies. In addition, because of the history of eugenics associated with genetic research, recruiting and studying majority EA populations avoided the need to confront challenging issues raised by studying race and genetics.52,53 Furthermore, the majority of GWAS conducted in the United States have used existing cohorts. These cohorts were mostly created before there was an increased effort to include minority populations in biomedical research and therefore, only included persons of a single ancestral background, which was usually that of the majority European descent population.54
