Recent meta-analyses confirmed a small but reliable association between schizophrenia and the cysteine-coding allele of the Cys311Ser polymorphism of DRD2.
Of the 183 SNPs successfully genotyped, only 1 SNP, rs6277 (C957T) in the DRD2 gene (P=0.0010, odds ratio=1.76), was considered to be significantly associated with schizophrenia after the replication study using independent sample sets.
Though no association was found between the TaqIA polymorphism and schizophrenia, a haplotype-wise analysis revealed a lower frequency of the T-C (C957T-TaqIA) haplotype in patients (p=0.02).
We propose that an interaction of the DRD2 C957T and COMT Val158Met may be involved in the generation of some working memory deficits in schizophrenia.
This work has implications for a number of psychiatric conditions in which dopamine signaling and variation in C957T status have been implicated, including schizophrenia and substance use disorders.
Our meta-analysis suggests an association of the DRD2 gene and the risk for schizophrenia, given that TaqI and C957T polymorphisms presented a protective effect against schizophrenia, and in the sub-analyses the C957T variant increased the risk for this disorder in the Chinese population.
In a cross-sectional study, we examined 2 dopamine D2 receptor (DRD2) single-nucleotide polymorphisms (SNPs) previously associated with schizophrenia (C939 T, rs6275 and C957 T, rs6277) along with fasting blood glucose and body mass index (BMI) in 207 antipsychotic-treated patients with schizophrenia.
Our results are in agreement with an earlier association study suggesting that the C957T C-allele plays a role in the genetic vulnerability for schizophrenia and support the involvement of the DRD2 gene in schizophrenia pathogenesis.
Remarkably, alleles of <i>COMT</i> rs165774 (G), <i>DRD2</i> rs6277 (T), and <i>DRD3</i> rs6280 (C) were associated with raised predisposition to schizophrenia (all <i>P</i><0.001).
Thus the aim of the present study was to investigate the possible association between the -141 Ins/Del (rs1799732) polymorphism of the dopamine receptor type 2 (DRD2) and schizophrenia.
A single nucleotide polymorphism, -141C insertion/deletion (Ins/Del) (rs1799732), in the promoter region of the dopamine D2 receptor gene has been linked to schizophrenia; however, the data are inconclusive.
To test the hypothesis that DRD2 polymorphisms are associated with schizophrenia, we investigated two DRD2-related polymorphisms (TaqI A1/A2 or rs1800497 and -141-C Ins/Del or rs1799732) in a Spanish population isolate from northern Spain consisting of 165 controls and 119 patients with schizophrenia.
Moreover, we found that rs1076560 T carrier/rs6314 CC individuals had better responses to antipsychotic treatment in two independent samples of patients with schizophrenia (n=63 and n=54, respectively), consistent with the previously reported separate effects of these genotypes.
Collectively, this work implicates rs1076560(T) as one possible risk factor for schizophrenia in the Han Chinese population, and suggests molecular mechanisms by which it may exert such influence.
In a cross-sectional study, we examined 2 dopamine D2 receptor (DRD2) single-nucleotide polymorphisms (SNPs) previously associated with schizophrenia (C939 T, rs6275 and C957 T, rs6277) along with fasting blood glucose and body mass index (BMI) in 207 antipsychotic-treated patients with schizophrenia.