ABSTRACT
<p><b>OBJECTIVE</b>To explore the molecular genetic mechanism of complicating depression in asthma by detecting two gene polymorphisms of 5-hydroxytryptamine transporter (5-HTTLPR/Stin2) gene.</p><p><b>METHODS</b>One hundred fifty-six adults with asthma were collected, and divided into group of asthma with depression (HAMD score > or = 8) and group of asthma without depression or single asthma (HAMD score <8) according to the score of Hamilton depression scale (HAMD). A total of 508 adults with depression alone and 433 healthy individuals were enrolled as controls. The target gene fragments containing the polymorphic regions of 5-HTTLPR and Stin2 were amplified by polymerase chain reaction (PCR). The amplified fragments were then analyzed using agarose gel electrophoresis (AGE) and motored molecular imaging system.</p><p><b>RESULTS</b>The frequencies of genotype and allele distribution of the Stin2 polymorphism showed that males with genotype Stin2.12/Stin2.10 and allele Stin2.10 had higher risk for asthma than the others (Stin2.12/Stin2.10: OR = 2.291, 95% CI: 1.195 and 4.390; Stin2.10: OR = 1.942, 95% CI: 1.069-3.527). No significant difference was found in the frequencies of genotype and allele distribution of the 5-HTTLPR locus between the asthma and healthy control groups and the two stratified by gender.</p><p><b>CONCLUSION</b>The Stin2 polymorphism may play a role in the onset of male asthma. There might be association between the genetic pathogenesis of asthma and depression.</p>