SNAP25 is associated with schizophrenia and major depressive disorder in the Han Chinese population

Synaptosomal-associated protein of 25 kDa (SNAP25) is a member of the soluble N-ethylmaleimide-sensitive factor attachment receptor (SNARE) protein complex, which plays essential roles in the modulation of different voltage-gated calcium channels and neurotransmitter release. Many previous studies have reported the SNAP25 gene to be significantly associated with attention-deficit/hyperactivity disorder (ADHD). Recently, shared genetic variants have been demonstrated in 5 major psychiatric disorders, including schizophrenia, major depressive disorder, bipolar disorder, autism spectrum disorders, and ADHD. However, no compelling, convincing evidence has suggested an association between SNAP25 and schizophrenia or major depressive disorder. Thus, we investigated the association between SNAP25 and both schizophrenia and major depressive disorder in the Han Chinese population.

We performed a large-scale case-control study to test the association between SNAP25 and 2 major mental disorders, schizophrenia (DSM-IV criteria) and major depressive disorder (DSM-IV criteria), in the Han Chinese population. Seven single-nucleotide polymorphisms (SNPs) were genotyped in 1,330 schizophrenia patients, 1,045 major depressive disorder patients, and 1,520 healthy controls of Han Chinese origin.

Two SNPs, rs3787283 and rs3746544, were found to be associated with both schizophrenia (rs3746544, adjusted P = .00257) and major depressive disorder (rs3746544, adjusted P = .0485; rs3787283, adjusted P = .00387) in this study. The AG haplotype consisting of rs3787283 and rs3746544 was also significantly associated with both schizophrenia and major depressive disorder (schizophrenia: adjusted P = .0126; major depressive disorder: adjusted P = .000580). Additionally, we carried out a meta-analysis of the current data and published association results and further confirmed the association between rs3746544 and schizophrenia (Pmeta = .002, ORmeta = 1.213 [95% CI, 1.077-1.367]).

Our results indicated that SNPs in SNAP25 represented a common risk factor of both schizophrenia and major depressive disorder in the Han Chinese population.