title: Variation in the BDNF Val66Met polymorphism and response to cognitive-behavior therapy in obsessive-compulsive disorder.
abstract: BACKGROUND
  Recent research suggests that the brain-derived neurotrophic factor (BDNF) may play a role in extinction learning. The goal of this study was to test whether variation in the BDNF Val66Met polymorphism is related to treatment response to exposure-based cognitive-behavior therapy (CBT), a form of extinction learning, in obsessive-compulsive disorder (OCD).
  
  
  METHODS
  One hundred and six OCD patients from a specialized clinic, who underwent a standardized CBT treatment after partial or non-response to a 12-week pharmacological trial, were genotyped for the BDNF Val66Met and the relationship between genotype and treatment response was analyzed.
  
  
  RESULTS
  Among 98 CBT completers, 36% of those carrying the BDNF Met allele were rated as CBT responders compared to 60% of nonMet allele carriers (P=0.027). When analyzing the different obsessive-compulsive symptom dimensions, in patients with contamination/cleaning symptoms, the Met allele was associated with a significantly worse CBT response (P<0.0001) and a lower obsessions severity decrease from pre- to posttreatment (P=0.046).
  
  
  CONCLUSIONS
  Genetic variation in BDNF may be associated with treatment response in exposure-based CBT in OCD, especially in those patients exhibiting contamination/cleaning symptoms.
authors.affiliation: Department of Psychological Medicine, Institute of Psychiatry, King's College London, United Kingdom. Miguel.Fullana@kcl.ac.uk
authors.forename: M A
authors.initials: MA
authors.lastname: Fullana
authors.forename: P
authors.initials: P
authors.lastname: Alonso
authors.forename: M
authors.initials: M
authors.lastname: Gratacòs
authors.forename: N
authors.initials: N
authors.lastname: Jaurrieta
authors.forename: S
authors.initials: S
authors.lastname: Jiménez-Murcia
authors.forename: C
authors.initials: C
authors.lastname: Segalàs
authors.forename: E
authors.initials: E
authors.lastname: Real
authors.forename: X
authors.initials: X
authors.lastname: Estivill
authors.forename: J M
authors.initials: JM
authors.lastname: Menchón
mesh_terms: D000328:Adult; D000483:Alleles; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D015928:Cognitive Behavioral Therapy; D005260:Female; D059647:Gene-Environment Interaction; D014644:Genetic Variation; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D009771:Obsessive-Compulsive Disorder / Q000235:genetics* / Q000523:psychology / Q000628:therapy*; D020641:Polymorphism, Single Nucleotide; D016896:Treatment Outcome
chemical_list: D019208:Brain-Derived Neurotrophic Factor