Allele polymorphism of genes and clinical indices in children and adolescents patients with

In the article the results of molecular-genetic research of 57 patients of schizophrenia with the early age at onset (under 15 years) are presented. Polymorphisms of the brain-derived neurotrophic factor gene, the serotonin transporter gene, the serotonin 2A receptor gene (5HTR2A), the dopamine D2 receptor gene (DRD2) are studied. The association of combinations of allelic variants with risk of disease development was found. There were significant differences between variant of genotype and age of disease onset. Patients with the Val/Val BDNF genotype and the T/T or C/T DRD2 genotype had earlier onset of disease compared to other genotypes. It was found that carriers of the Val/Val BDNF genotype had lower level of social functioning. The effect of genotype-environment interactions between the DRD2 gene and the level of social functioning was revealed. The index of the social functioning was significantly lower in patients with the CC genotype and birth trauma as compared to patients with the same genotype without birth trauma.