Association between major depressive disorder and the -1438A/G polymorphism of the serotonin 2A receptor gene.

This study investigated the possible effect of the -1438A/G single-nucleotide polymorphism in the promoter region of the serotonin 2A receptor (5-HTR2A) gene on major depressive disorder (MDD) in a Korean population. This polymorphism was analyzed in 189 patients with MDD and in 148 unrelated healthy controls using a case-control design, which revealed a significant difference in the genotype distributions (chi(2) = 10.78, d.f. = 2, p = 0.005). The frequency of the -1438G allele was also much higher in MDD patients than in normal controls (chi(2) = 7.20, p = 0.007; OR = 1.52, 95% CI 1.12-2.06). We also found significantly more carriers of the G allele (GG+AG genotypes) in MDD patients than in normal controls (chi(2) = 10.18, p = 0.001; OR = 2.46, 95% CI 1.40-4.32). Our results support the hypothesis that the -1438A/G polymorphism of the promoter region of the 5-HTR2A gene is associated with MDD patients in a Korean population.