title: The brain-derived neurotrophic factor gene in suicidal behaviour: a meta-analysis.
abstract: Suicide is a prominent public health problem. Its aetiology is complex, and the brain-derived neurotrophic factor (BDNF) has been implicated. We performed the first meta-analysis of the functional BDNF marker Val⁶⁶Met (rs6265, 196G>A) in suicidal behaviour using data from 11 previously published samples plus our present sample (total n=3352 subjects, 1202 with history of suicidal behaviour. The meta-analysis including all 12 studies showed a trend for the Met-carrying genotypes and Met allele conferring risk for suicide (random-effects model p=0.096; ORMet-carrier=1.13, 95% CI 0.98-1.30, and random-effects model p=0.032; ORMet=1.16, 95% CI 1.01-1.32, respectively). Furthermore, we found the Met allele and the Met allele-carrying genotypes to be associated with history of suicide attempt (eight studies; allelic meta-analysis--random-effects model: p=0.013; fixed-effects model: p=0.006; genotypic meta-analysis--random-effects model: p=0.017; fixed-effects model: p=0.008). Taken together, the results from our study suggest that BDNF Val⁶⁶Met is involved in suicidality. Further studies are required to elucidate its role in suicidal behaviour.
authors.affiliation: Neurogenetics Section, Centre for Addiction and Mental Health, Toronto, ON, Canada. clement_zai@camh.net
authors.forename: Clement C
authors.initials: CC
authors.lastname: Zai
authors.forename: Mirko
authors.initials: M
authors.lastname: Manchia
authors.forename: Vincenzo
authors.initials: V
authors.lastname: De Luca
authors.forename: Arun K
authors.initials: AK
authors.lastname: Tiwari
authors.forename: Nabilah I
authors.initials: NI
authors.lastname: Chowdhury
authors.forename: Gwyneth C
authors.initials: GC
authors.lastname: Zai
authors.forename: Ryan P
authors.initials: RP
authors.lastname: Tong
authors.forename: Zeynep
authors.initials: Z
authors.lastname: Yilmaz
authors.forename: Sajid A
authors.initials: SA
authors.lastname: Shaikh
authors.forename: John
authors.initials: J
authors.lastname: Strauss
authors.forename: James L
authors.initials: JL
authors.lastname: Kennedy
mesh_terms: D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D008715:Methionine / Q000235:genetics; D016017:Odds Ratio; D013405:Suicide; D014633:Valine / Q000235:genetics
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D008715:Methionine; D014633:Valine