These analyses evaluated genomic influences on alcohol problems in ALSPAC, a population-based sample of emerging adults. Results from GCTA suggest that such influences are modest in this sample, accounting for ~5% of the variance in an alcohol problems factor score. Although only one individual polymorphism met genome-wide significance criteria, several genes surpassed a stringent multiple testing threshold, two of which (NLRP12 and SLC2A2) have putative roles in immune function. Furthermore, gene ontologies related to immune and nervous system processes were statistically over-represented, along with categories that warrant further consideration. Bioinformatic analyses suggest that SNPs meeting increasingly stringent p-value thresholds are generally more likely than is expected by chance to map to regulatory regions; tissue derived from monocytes and spinal cord exhibited the most striking evidence of such enrichment. Our findings provide potential insight into the biological context of genomic influences on this complex behavior, and suggest that environmental factors remain strongly influential on liability to alcohol problems in this sample.
