LD (r2 = 0.3–0.7) with several SNPs that have been identified as cis-eQTLs for SRD5A1 in post-mortem samples from cerebellum and parietal cortex [83]. Rs472402 is also in strong LD with rs248793 (r2 = 0.89), which has been associated with differences in SRD5A1 activity [84] and with risk for alcohol dependence [85]. Finally, SRD5A1 has also been suggested as a positional candidate gene based on a linkage study for cocaine dependence and major depressive episode [86]. Taken together these results suggest that SNPs in SRD5A1 could influence subjective positive affect by modulating both expression and enzymatic activity of SRD5A1 and thereby altering allopregnanolone levels in the brain.
