Conversely, a subset of SNP:probe pairs reached significance in the brain samples but not in blood (Figs. 3A,B and Supplementary Table 1). For example, rs713586, which was nominated for association with body mass index (PMID: 20935630), was significantly associated with the expression of ILMN_1676893 in cerebellum (FDR corrected P = 6.09x10− 5) and frontal cortex (FDR corrected P = 1.53 × 10− 8) but showed no association in blood (FDR corrected P = 0.89). This probe maps to the adenylate cyclase gene ADCY3 on chromosome 2 (Fig. 4A). Interestingly, variation in ADCY3 has been nominated in a number of GWAS including for alcohol dependence (Edenberg et al., 2010) and major depression (Wray et al., 2010).
