Methylation of APC2, NR3C1, and DRD2 gene promoters in turkish patients with tobacco use disorder.

Abstract

Many studies have investigated the association of the methylation of gene and tobacco use disorders (TUD), but results remain ambiguous. This study evaluated the relationship between methylation of Adenomatosis Polyposis Coli (APC), Nuclear Receptor subfamily 3 group C member 1 (NR3C1), Dopamine D2 receptor (DRD2) gene promoters, and its effect on TUD. We recruited 154 active smokers and 111 healthy non-smoker controls. PCR based methods on genomic DNA characterized the methylation of APC2, NR3C1, and DRD2 gene promoters. We have found a significant difference in methylation of APC2 for TUD compared to healthy controls (P < 0.001). The partial methylation ratio was about an eight-fold increase in smokers compared to healthy controls. NR3C1 methylation was slightly higher in TUD patients compared to the control group, but the difference was not significant between the two groups (%95.33 vs. 91.08, P = 0.269). DRD2 methylation ratio was not significant between TUD patients and healthy control groups (P = 0.894). We think that it is important to detect APC2 methylated cases earlier and to advise them to quit smoking.