The dopamine, serotonin and glutamate systems are jointly involved in the pathogenesis and pharmacotherapy of schizophrenia. We formulated a hypothesis that polymorphic variants of the GRIN2A, GRM3, and GRM7 genes may be associated with the development of hyperprolactinemia in patients with schizophrenia taking conventional and atypical antipsychotics as basic treatment. 432 Caucasian patients diagnosed with schizophrenia were examined. DNA was isolated from peripheral blood leukocytes using the standard phenol-chloroform method. For pilot genotyping, 12 SNPs in the GRIN2A gene, 4 SNPs in the GRM3 gene, and 6 SNPs in the GRM7 gene were selected. Allelic variants of the studied polymorphisms were determined by real-time PCR. The level of prolactin was determined by enzyme immunoassay. Among persons taking conventional antipsychotics, there were statistically significant differences in the distribution of genotype and allele frequencies in groups of patients with normal and elevated prolactin levels for the GRIN2A rs9989388 and GRIN2A rs7192557 polymorphic variants, as well as differences in serum prolactin levels depending on the genotype of the GRM7 rs3749380 polymorphic variant. Among persons taking atypical antipsychotics, statistically significant differences were found in the frequencies of genotypes and alleles of the GRM3 rs6465084 polymorphic variant. An association of polymorphic variants of the GRIN2A, GRM3, and GRM7 genes with the development of hyperprolactinemia in patients with schizophrenia taking conventional and atypical antipsychotics has been established for the first time. The identified associations of polymorphic variants of the GRIN2A, GRM3 and GRM7 genes with the development of hyperprolactinemia in patients with schizophrenia taking conventional and atypical antipsychotics have been established for the first time. These associations not only confirm the close connection of the dopaminergic, serotonergic, and glutamatergic systems in the development of schizophrenia, but also demonstrate the potential of taking into account the genetic component during therapy.
Keywords: ELISA; antipsychotics; glutamate; human; molecular genetics; prolactin; real-time PCR; schizophrenia; single nucleotide polymorphisms.