In EAs, 6 CpGs in 6 genes (HTR3A, NCAM1, DRD4, MBD3, HTR2B, and GRIN1) were hypermethylated in AD cases compared with controls (p ≤ 0.001); CpG cg08989585 in the HTR3A promoter region showed a significantly higher methylation level in EA cases than in EA controls after Bonferroni correction (p = 0.00007).
Apomorphine challenge tests measuring GH responses on 5 time points were performed on day 1 of alcohol detoxification in 43 patients with alcohol dependence; patients were genotyped for 11 polymorphisms including DRD2, ANKK1, NCAM1 and TTC12.
We conclude that risk for AD is attributable in part to variants in four regions within this cluster: exon 3 of TTC12, exon 12/intron13 of NCAM1 and exons 2 and 5 of ANKK1.