title: Association of the Brain-derived Neurotrophic Factor Gene and Clinical Features of Bipolar Disorder in Korea.
abstract: OBJECTIVE
  Brain-derived neurotrophic factor (BDNF) plays an important role in cell survival, differentiation, and cell death as well as in neural plasticity. Recent studies have suggested that BDNF is involved in the pathogenesis of bipolar disorder. The aim of this study was to investigate the association of the genetic variations of the BDNF gene with bipolar disorder in Korea. We also studied the possible association of these genetic variants with clinical features.
  
  
  METHODS
  The allelic and genotypic distributions of Val66Met polymorphism of the BDNF gene were analyzed using a polymerase chain reaction-based method in 184 bipolar patients and 214 controls. Analysis was performed to investigate an association of the Val66Met polymorphism of the BDNF gene and the clinical features in bipolar patients.
  
  
  RESULTS
  No significant difference was found between bipolar patients and controls in the genotype and allele frequencies for the investigated BDNF polymorphism. However, the age of onset of bipolar disorder among the Val/Val (25.57), Val/Met (30.42) and Met/Met (32.45) genotype groups were significantly different (p=0.037).
  
  
  CONCLUSIONS
  This study suggests that Val66Met polymorphisms are unlikely to contribution to the genetic predisposition to bipolar disorder as a whole. But Val66Met polymorphism may be associated with age of onset of the disorder, further studies designed to investigate the relationship in a larger population may be warranted.
authors: Department of Psychiatry, Hallym University College of Medicine, Anyang, Korea.
authors: Hye Ji
authors: HJ
authors: Min
authors: Hyun-Sang
authors: HS
authors: Cho
authors: Se Joo
authors: SJ
authors: Kim
authors: Jeong-Ho
authors: JH
authors: Seok
authors: Eun
authors: E
authors: Lee
authors: Duk-In
authors: DI
authors: Jon
keywords: Age of onset; Bipolar disorder; Brain-derived neurotrophic factor; Polymorphism