title: Investigation of the genetic interaction between BDNF and DRD3 genes in suicidical behaviour in psychiatric disorders.
abstract: OBJECTIVE
  Suicide is a serious public health concern, and it is partly genetic. The brain-derived neurotrophic factor (BDNF) gene has been a strong candidate in genetic studies of suicide (Dwivedi et al., Arch Gen Psychiatry 2010;60:804-815; Zai et al., Prog Neuropsychopharmacol Biol Psychiatry 2012;34:1412-1418) and BDNF regulates the expression of the dopamine D3 receptor.
  
  
  OBJECTIVE
  We examined the role of the BDNF and DRD3 genes in suicide.
  
  
  METHODS
  We analysed four tag single-nucleotide polymorphisms (SNPs) in BDNF and 15 SNPs in the D3 receptor gene DRD3 for possible association with suicide attempt history in our Canadian sample of Schizophrenia (SCZ) patients of European ancestry (N = 188).
  
  
  RESULTS
  In this sample, we found a possible interaction between the BDNF Val66Met and DRD3 Ser9Gly SNPs in increasing the risk of suicide attempt(s) in our SCZ sample. Specifically, a larger proportion of SCZ patients who were carrying at least one copy of the minor allele at each of the Val66Met and Ser9Gly functional markers have attempted suicides compared to patients with other genotypes (Bonferroni P < 0.05). However, we could not replicate this finding in samples from other psychiatric populations.
  
  
  CONCLUSIONS
  Taken together, the results from the present study suggest that an interaction between BDNF and DRD3 may not play a major role in the risk for suicide attempt, though further studies, especially in SCZ, are required.
authors.affiliation: Neurogenetics Section, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health (CAMH) , Toronto, Ontario , Canada.
authors.forename: Clement C
authors.initials: CC
authors.lastname: Zai
authors.forename: Mirko
authors.initials: M
authors.lastname: Manchia
authors.forename: Ida Elken
authors.initials: IE
authors.lastname: Sønderby
authors.forename: Zeynep
authors.initials: Z
authors.lastname: Yilmaz
authors.forename: Vincenzo
authors.initials: V
authors.lastname: De Luca
authors.forename: Arun K
authors.initials: AK
authors.lastname: Tiwari
authors.forename: Alessio
authors.initials: A
authors.lastname: Squassina
authors.forename: Gwyneth C
authors.initials: GC
authors.lastname: Zai
authors.forename: Sajid A
authors.initials: SA
authors.lastname: Shaikh
authors.forename: John
authors.initials: J
authors.lastname: Strauss
authors.forename: Nicole
authors.initials: N
authors.lastname: King
authors.forename: Bernard
authors.initials: B
authors.lastname: Le Foll
authors.forename: Allan S
authors.initials: AS
authors.lastname: Kaplan
authors.forename: Per I
authors.initials: PI
authors.lastname: Finseth
authors.forename: Arne E
authors.initials: AE
authors.lastname: Vaaler
authors.forename: Srdjan
authors.initials: S
authors.lastname: Djurovic
authors.forename: Ole A
authors.initials: OA
authors.lastname: Andreassen
authors.forename: John B
authors.initials: JB
authors.lastname: Vincent
authors.forename: James L
authors.initials: JL
authors.lastname: Kennedy
mesh_terms: D000328:Adult; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D002170:Canada; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D050637:Receptors, Dopamine D3 / Q000235:genetics*; D012307:Risk Factors; D012559:Schizophrenia / Q000235:genetics*; D013406:Suicide, Attempted / Q000523:psychology*
chemical_list: D019208:Brain-Derived Neurotrophic Factor; C493593:DRD3 protein, human; D050637:Receptors, Dopamine D3; C579455:BDNF protein, human
keywords: brain-derived neurotrophic factor; dopamine receptor DRD3; genetics; schizophrenia; suicide