We measured suicidal ideation (SI) and suicide attempt (SA) history and the association of six gene polymorphisms with SB: COMT (rs4680), HTR1A (rs6295), TPH1 (rs1800532), BDNF (rs6265), SLC1A3 (rs2269272), and SLC1A2 (rs4755404).
We focused on the catechol-O-methyltransferase gene (COMT) and we performed: a review of studies investigating the association between COMT and both suicidal behavior and personality; a meta-analysis of studies investigating the association between suicidal behavior and COMT rs4680 polymorphism; an association study investigating the link between seven COMT polymorphisms (rs737865, rs5844402, rs5993883, rs4680, rs4633, rs165599 and rs9332377) and both personality traits and suicidal behavior.
In the present sample the triallelic 5-HTTLPR polymorphism (S, L(G), L(A)) was not associated with MAP-induced depressive disorder, MAP-induced psychotic disorder or suicidal behavior, but studies with larger sample sizes are warranted before excluding the role of the 5-HTTLPR polymorphisms in suicidal behavior among MAP abusers.
This study suggests that the 5-HTTLPR polymorphism is unlikely to have major relevance to the pathogenesis of suicidal behavior in adolescence but may contribute to violent behavior in this population.
We measured suicidal ideation (SI) and suicide attempt (SA) history and the association of six gene polymorphisms with SB: COMT (rs4680), HTR1A (rs6295), TPH1 (rs1800532), BDNF (rs6265), SLC1A3 (rs2269272), and SLC1A2 (rs4755404).
Except for the possible heterogeneity between inpatients with a first episode of suicidal behavior and those with more than one, the 5-HTT gene was unlikely to be associated with suicidal behavior of psychotic patient in Han Chinese.
The C allele of the T102C polymorphism of the 5-HT2A receptor gene may be associated with biological susceptibility for suicidal behavior or psychiatric conditions.
The findings support an association between the COMT gene and suicidal behaviour phenotypes with and without childhood maltreatment as environmental factor.
Significant interactions were observed between 5-HTTLPR genotype, SLEs and SSDs on both prevalence and incidence of suicidal ideation after adjustment for covariates.
Altogether, the baseline level and the changes in SLC6A4 mRNA expression during a MDE might predict the WSI and the occurrence of suicidal attempts and could be a useful biomarker in clinical practice.
The results for COMT support past literature that has found a relationship between suicidal behavior and COMT, and has also found that the relationship differs for males and females.
The main aim of the current study was to investigate epigenetic alterations in serotonin 2A receptor (HTR2A) exon I CpG sites as possible risk factors for suicidal behavior.
Six polymorphisms in four genes related to the serotonin system, including the HTTLPR and HTTVNTR in the SLC6A4 gene, rs6295 in the HTR1A gene, rs11568817 and rs130058 in the HTR1B gene, and rs6313 in the HTR2A gene, were studied in 420 patients with MD to investigate the relationship between these genes and suicidal ideation in MD.
Further research is necessary to understand how early life stress interacts with 5-HTT genotypes to confer risk for suicidal behavior through psychological mechanisms.
Thus, the genetically altered expression of the 5-HT transporter might be associated with more severe or violent suicidal behavior, but not with non-violent suicidal behavior.
The authors conclude that the A218C polymorphism of the TPH gene may not be a susceptibility factor for suicidal behavior in this group of psychiatric patients but confirm that a family suicidal behavior history increases the proband's suicide attempt risk.
Patients homozygous for the C allele of the T102Cserotonin (5-HT) 2a receptor polymorphism have shown increased suicidal ideation or behavior in some reports, but not in others.
However, our linkage disequilibrium analyses indicated that there may be a greater risk for suicidal behavior in carriers of the S10 and L12 alleles of 5-HTTLPR.