We utilized a three-stage design consisting of a GWAS meta-analysis (Stage 1), a follow-up of 1,500 SNPs (Stage 2), and a focused follow-up of the three novel loci (Stage 3). Stage 1 included results from 36GWAS of 39,144 men and women of African ancestry (37,956 African American and 1,188 African; Supplementary Table 1). We took forward the 1,500 most significantly associated SNPs (p-value <0.0003) for examination in 6,817 additional men and women of African ancestry from seven GWAS (Stage 2, all African American). The three SNPs that reached genome-wide significance (p<5×10−8) after the meta-analysis of Stage 1 and Stage 2 results were taken forward for further confirmation in 25,451 additional African ancestry subjects from twelve studies. All participants in these studies provided written informed consent for the research, and approval for the study was obtained from the ethics review boards at all institutions. A description of each participating study as well as details regarding the measurement and collection of height and weight data are provided in the Supplementary Note.
