The top novel nicotine dependence-associated variant was assessed for cis-acting regulatory effects, using previously published methylation quantitative trait locus (meQTL) and expression QTL (eQTL) studies of postmortem brain tissues (Supplementary Methods). We used meQTL results from 166 fetal brain samples in the Human Developmental Biology Resource and UK Medical Research Council Brain Banks network; these samples were not dissected further into different tissues.36 SNP genotypes were imputed using 1000G, and DNAm was measured using the Illumina HumanMethylation450 BeadChip. meQTL results were obtained at http://epigenetics.essex.ac.uk/mQTL/.
