SLC6A3 and congenital primary aphakia: High physical aggression was associated with clustered and genome-wide variations in promoter methylation. Within the plenty, 227 gene loci were significantly more methylated in the control group (including 10 micro RNA promoters) and 171 were significantly more methylated in the CPA group (including 2 microRNA promoters). Five of the genes were already described to be linked with aggression: AVPR1A, HTR1D, GRM5 were less methylated in the CPA group and DRD1 and SLC6A3 were hypermethylated.