Association analysis between two functional dopamine D2 receptor gene polymorphisms and schizophrenia

The dopamine D2 receptor (DRD2) gene has been listed as one of the candidat e genes for susceptibility to schizophrenia. To date, a significant associa tion between schizophrenia and two functional DRD2 gene polymorphisms, Ser3 11Cys and -141C Ins/Del, in Japanese samples, has been reported by Arinami ct al, [1994: Lancet 343:703-704; 1997: Hum Mol Genet 6:577-582], In the pr esent study, we replicated the findings of Arinami ct al, [1994: Lancet 343 :703-704; 1997: Hum Mol Genet 6:577-582] in the same ethnic groups (Japanes e samples) with the same polymorphisms (Ser311Cys and -141C Ins/Del), We ge notyped these two polymorphisms for 241 patients and for 201 controls. Neit her polymorphism was associated with schizophrenia. Moreover, in a haplotyp e analysis of the present sample, combined pairs of two polymorphisms provi ded no evidence for the association of either haplotype with schizophrenia. Our findings indicate that an association between the two functional DRD2 gene polymorphisms, Ser311Cys and -141C Ins/ Del, and schizophrenia is unli kely. (C) 2001 Wiley-Liss, Inc.