A case control study investigating the methylation levels of GHRL and GHSR genes in alcohol use disorder

Background Alcohol use disorder (AUD) is a relapsing disease described as excessive use of alcohol. Evidence of the role of DNA methylation in addiction is accumulating. Ghrelin is an important peptide known as appetite hormone and its role in addictive behavior has been identified. Here we aimed to determine the methylation levels of two crucial genes ( GHRL and GHSR ) in ghrelin signaling and further investigate the association between methylation ratios and plasma ghrelin levels. Methods Individuals diagnosed with ( n = 71) and without ( n = 82) AUD were recruited in this study. DNA methylation levels were measured through methylation-sensitive high-resolution melting (MS-HRM). Acylated ghrelin levels were detected by ELISA. The GHRL rs696217 polymorphism was analyzed by the standard PCR-RFLP method. Results GHRL was significantly hypermethylated ( P