Abstract
This study was conducted to explore the possibility of association between the single-nucleotide polymorphisms rs6264 of BDNF, rs5443 of GNB3, and rs1801133 of MTHFR; the In/Del polymorphism of ACE; and the ε2 allele of APOE and major depressive disorder (MDD) and recurrent depressive disorder (RDD) in an East Slavic population. Generalized multifactor dimensionality reduction (GMDR) method was applied to detect gene-gene interactions. One hundred fifty patients with RDD (101 females and 49 males) and 208 patients with MDD (115 females and 93 males) were included in the study. The comparison group consisted of 200 unrelated individuals. There was no significant difference in genotype distributions or allele frequencies between the controls and any of the diagnostic groups. Nevertheless, the frequency of the G allele of rs1801133 of MTHFR was higher in the RDD group and the frequency of the C allele of rs6264 of BDNF was higher in the MDD group. The difference between the controls and specific disease groups almost reached statistical significance (P = 0.08). A GMDR did not reveal optimal two- and three-dimensional models with significant prediction accuracies (P ˃ 0.05) for the MDD or RDD groups.