Dihydropyrimidinase‐related protein 2 ( DRP‐2 ) gene and association to deficit and nondeficit schizophrenia

A previous study has shown an association between the *2236T > C allele polymorphism of the dihydropyrimidinase‐related protein 2 ( DRP‐2 ) gene and schizophrenia in a Japanese sample [Nakata et al. (2003); Biological Psychiatry 53:571–576]. DRP‐2 is an important molecule in guiding neuronal development and its gene is located in 8p21, a chromosomal region that was previously shown to have significant linkage to schizophrenia and to several deficit symptoms of schizophrenia. We compared the frequency of the DRP‐2 *2236T > C polymorphism between subjects with (n = 117) and without (n = 72) schizophrenia, and then further evaluated whether the association was specific for the deficit (n = 24) and nondeficit (n = 93) forms of schizophrenia. In both Caucasians and African‐Americans, the C allele occurred more frequently in schizophrenia cases than controls, with this difference achieving statistical significance in Caucasians (C allele frequency: 42.0% in cases vs. 25.0% in controls, P  = 0.014) but not African Americans (52.6% in cases vs. 50.0% in controls, P  = 0.93). In Caucasians, the frequency of the C allele was significantly higher in both the deficit (allele frequency 53.3%, P  = 0.009) and nondeficit (39.2%, P  =0.050) forms of schizophrenia compared to controls (allele frequency 25.0%). We conclude that the DRP‐2 *2236 C allele may mark another polymorphism in DRP‐2 , or in a nearby gene, that may influence susceptibility to schizophrenia. © 2005 Wiley‐Liss, Inc.