Association study between MAO-A gene promoter VNTR polymorphisms and obsessive-compulsive disorder.

A functional variant in the mono-amine oxidase-A (MAO-A) gene has been shown to affect neural function related to several mental disorders. Therefore, we would like to ascertain if MAO-A could be a candidate gene for obsessive-compulsive disorder (OCD). We genotyped 414 healthy subjects and 240 OCD patients and found no significant difference not only in allele frequencies in male patients (χ(2) = 0.365, DF = 1, P = 0.545, odds ratio (OR) = 1.139, confidence interval (CI) = 0.75-1.74) but also in allele frequencies (χ(2) = 0.698, DF = 1, P = 0.404, OR = 0.849, CI = 0.579-1.246) or genotypic frequencies (χ(2)=0.933, DF = 2, P = 0.627) in female patients between OCD patients and controls. Given that this is the first investigation of this gene in OCD in a Chinese Han population, further studies are required to obtain more definitive conclusions in a larger number of subjects.