Association Study of Dopamine β-Hydroxylase Gene with Methamphetamine Psychosis

Dopamine is a key molecule in the pathophysiology of methamphetamine (METH) psychosis. We examined the association between METH psychosis and the dopamine β-hydroxylase (DBH) gene, which modulates dopaminergic cascades. Six polymorphisms, rs1989787, rs1611115, rs1108580, rs5320, rs1611125, and rs6271, of the DBH gene were genotyped. These polymorphisms were not associated with METH-seeking behaviors of patients with METH psychosis (N = 216) or healthy controls (N = 328), but rs1611125 affected one of the clinical phenotypes of METH psychosis. Individuals with the G/G homozygote of rs1611125 had a significant risk for spontaneous relapse of METH psychosis (P = .02, odds ratio = 2.2). In haplotype analyses, rs1108580-rs5320-rs1611125 was revealed to be associated with METH psychosis (P = .01). Having G-Ala-G was a significant risk factor, while A-Thr-A was a protective factor for METH psychosis (odds ratio were 9.9 and 0.16, resp.). Our present findings indicated that the DBH gene may play an important role in METH psychosis.