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 demonstrated initial significant associations of two SNPs for DRD2 (rs11608185, genotype: chi(2) = 6.29, p-value = 0.043; rs6275, genotype: chi(2) = 8.91, p-value = 0.011), and one SNP in the COMT gene (rs4680, genotype: chi(2) = 6.67, p-value = 0.035 and allele: chi(2) = 4.75, p-value = 0.029; odds ratio: 1.33, 95% confidence interval: 1.02-1.73), but not after correction for multiple comparisons indicating a weak association of individual markers of DRD2 and COMT with schizophrenia.
To replicate and extend previous findings, we conducted an association study of the C957T polymorphism and two additional SNPs (C939T and TaqIA) in 311 patients with a DSM-IV diagnosis of schizophrenia and 364 mentally healthy people from the Russian population as controls.