We conducted additional analyses to attempt to localize the association depicted in Figure 2. Imputation (56) supported the directly typed SNP associations but did not yield an association p-value markedly more significant than any directly genotyped SNP (although 22 of the 25 most significant imputed associations in the genome were in this region). Haplotype analysis using 3-SNP sliding windows did not improve localization. Secondary analyses by sex, case ascertainment setting, and recurrent early-onset MDD (reoMDD, arguably the most heritable form of MDD) (16, 78) suggested that most of the signal was from females and from subjects with reoMDD (Supplemental Table 11). The findings for reoMDD were often stronger than the primary analyses, particularly for the most significant SNP (rs2715148) where the p-value decreased by 1.2 orders of magnitude to 9.5×10−8.
