Interaction between HTR2A rs3125 and negative life events in suicide attempts among patients with major depressive disorder: a cross-sectional study.

BACKGROUND: Both genetic and environmental factors play crucial roles in the development of major depressive disorder (MDD) and suicide attempts (SA). However, the interaction between both items remains unknown. This study aims to explore the interactions between the genetic variants of the serotonin 2 A receptor (HTR2A) and the nitric oxide synthase 1 (NOS1) and environmental factors in patients who experience MDD and SA. METHODS: A total of 334 patients with MDD and a history of SA (MDD-SA) were recruited alongside 518 patients with MDD with no history of SA (MDD-NSA), and 716 healthy controls (HC). The demographic data and clinical characteristics were collected. Sequenom mass spectrometry was used to detect eight tag-single nucleotide polymorphisms (tagSNPs) in HTR2A (rs1328683, rs17068986, and rs3125) and NOS1 (rs1123425, rs2682826, rs3741476, rs527590, and rs7959232). Generalized multifactor dimensionality reduction (GMDR) was used to analyze the gene-environment interactions. RESULTS: Four tagSNPs (rs17068986, rs3125, rs527590, and rs7959232) exhibited significant differences between the three groups. However, these differences were not significant between the MDD-SA and MDD-NSA groups after Bonferroni correction. A logistic regression analysis revealed that negative life events (OR = 1.495, 95%CI: 1.071-2.087, P = 0.018), self-guilt (OR = 2.263, 95%CI: 1.515-3.379, P < 0.001), and negative cognition (OR = 2.252, 95%CI: 1.264-4.013, P = 0.006) were all independently associated with SA in patients with MDD. Furthermore, GMDR analysis indicated a significant interaction between HTR2A rs3125 and negative life events. Negative life events in conjunction with the HTR2A rs3125 CG + GG genotype were associated with a higher SA risk in patients with MDD when compared to the absence of negative life events in conjunction with the CC genotype (OR = 2.547, 95% CI: 1.264-5.131, P = 0.009). CONCLUSION: Several risk factors and a potential interaction between HTR2A rs3125 and negative life events were identified in patients with SA and MDD. The observed interaction likely modulates the risk of MDD and SA, shedding light on the pathogenesis of SA in patients with MDD.

Association between T-182C, G1287A polymorphism in NET gene and suicidality in major depressive disorder in Chinese patients.

Objective: Previous studies have implicated norepinephrine transporter gene (NET) polymorphisms in the etiology of major depressive disorder (MDD). A functional NET T-182C polymorphism (rs2242446) in the promoter region and a synonymous polymorphisms G1287A in the exon 9 (rs5569) were associated with MDD in different populations. However, few studies have focused on the relationship between these polymorphisms and MDD patients with suicidality. The objective of the present study was to examine whether the two polymorphisms are associated with MDD patients with suicidality in the Han Chinese population. Methods: Two hundred and sixty-three suicidal depressed patients and 241 non-suicidal depressed patients who met DSM-IV criteria for MDD were recruited from our hospital. Three hundred and three unrelated, age- and sex-matched healthy control subjects participated in this case-control study. Suicidality was assessed using Mini International Neuropsychiatric Interview (MINI) and the Hamilton rating scale for depression (HAMD). Genotypes of T-182C polymorphism (rs2242446) and G1287A (rs5569) were screened by polymerase chain reaction. Results: No statistical significant differences between patients and controls were found for any of the analysed polymorphisms, either in the genotype or allele distribution. Conclusions: Our results suggest that the investigated polymorphisms are not major susceptibility factors in the etiology of MDD with suicidality. However, the results must be verified in larger samples and different ethnicities.