Ghrelin precursor gene polymorphism and methamphetamine dependence in the Korean population

Ghrelin is a recently isolated brain-gut peptide that has growth hormone-releasing and appetite-inducing activities. Several recent studies have suggested that ghrelin plays a major role in the pathophysiology of drug-seeking behavior and anxiety. Therefore, we assessed the effect of the ghrelin precursor polymorphism oil methalrphetamine dependence in the Korean Population. One hundred and eighteen patients with methamphetamine dependence, according to the Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) criteria, and the 144 healthy controls were enrolled in this study. Genotyping for the ghrelin precursor polymorphism was performed by the polymerase chain reaction-restriction fragment length polymorphism-based technique. The genotypic and allelic distributions of the ghrelin precursor polymorphism in the patients with methamphetamine dependence were not significantly different from those of the control subjects. However, the Met72 carriers were associated with the emotional problems of metharrpherainine dependence. The patients with the Met72 allele were more depressed and anxious than the homozygous patients with the wild Leu72 allele. The present study suggests that the ghrelin precursor polymorphisin may not confer a susceptibility to the development of methamplietamine dependence in the Korean population. However, the Let72Met polymorphism could have a potential role in the emotional problems that are associated with this disease. (c) 2005 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.