ABSTRACT
<p><b>BACKGROUND</b>Recent studies have suggested that susceptibility to major depressive disorder (MDD) might be related to the serotonin 1A receptor (5-HTR1A) C (-1019) G polymorphism. In this study, we aimed to assess the association between 5-HTR1A C (-1019) G polymorphism and MDD in the Northern Han ethnic group of China.</p><p><b>METHODS</b>The C (-1019) G of 5-HTR1A was detected with polymerase chain reaction (PCR) in 400 patients with MDD and 400 unrelated age- and sex-matched healthy control subjects. Association between the C (-1019) G and MDD was statistically analyzed.</p><p><b>RESULTS</b>There was a statistically significant difference between MDD patients and controls in both the genotype distribution (Chi(2) = 10.913, df = 2, P = 0.004) and the allele frequency (Chi(2) = 10.379, df = 1, P = 0.001), and a significant difference in the genotype distribution and the allele frequency was found both in the female subjects (Genotype distribution: Chi(2) = 15.406, df = 2, P = 0.000; allele frequency: Chi(2) = 15.552, df = 1, P = 0.000) and the late-onset subjects (Genotype distribution: Chi(2) = 7.771, df = 2, P = 0.021; allele frequency: Chi(2) = 8.007, df = 1, P = 0.005) in the two groups.</p><p><b>CONCLUSION</b>These results suggest that 5-HTR1A C (-1019) G polymorphism is probably associated with MDD and it is likely to be the susceptible gene locus for the female and late-onset MDD.</p>