Genomic DNA was isolated from blood using standard protocols. A genomic region containing sequence 5 kb upstream and 1 kb downstream of CRHBP was retrieved from NCBI Human Build 35.1. Haplotype-tagging SNPs, derived from the African HapMap sample, were identified using a previously described design pipeline (Hodgkinson et al., 2008). Eight CRHBP SNPs, listed in Table 1, were genotyped using the Illumina GoldenGate platform (Hodgkinson et al., 2008). Using the identical methodology, four CRH, nine CRHR1 and eleven CRHR2 haplotype-tagging SNPs were genotyped (Table 1). All SNPs were in Hardy–Weinberg equilibrium other than CRHBP rs32897 (p = 0.0001) that was excluded from analyses.
