Schizophrenia is a debilitating disorder caused by the interaction of genetic and environmental factors. In this study, we identified candidate genes and single nucleotide polymorphisms from two genome-wide association studies, GAIN and CATIE. Nine SNPs representing four candidate genes were selected for replication studies with our Irish samples: Irish Case-Control Study of Schizophrenia (ICCSS), the Irish Study of High-Density Schizophrenia Families (ISHDSF), and the Irish Trio Study of Schizophrenia (ITRIO). In the ITRIO sample, rs4704591 (CMYA5 gene) showed nominal significance (p = 0.0447947). Combining ICCSS, ISHDSF, and ITRIO samples for rs4704591 increased sample size and power and yielded a p-value of 0.00388. This marker remained significant after Bonferroni correction for 9 markers genotyped in this study. CMYA5 gene binds to dysbindin protein in muscle. The dysbindin gene may influence glutamatergic neurotransmission, which has been suspected of being a mechanism by which the pathophysiology of schizophrenia is manifest. Our data suggest CMYA5 gene may be associated with schizophrenia in Caucasian subjects
