title: Brain-derived neurotrophic factor G196A polymorphism and clinical features in Parkinson's disease.
abstract: OBJECTIVE
  Parkinson's disease (PD) is characterized by the dopaminergic neuronal death in substantia nigra, and genetic factors appear to be involved in the pathophysiology of this disease. Brain-derived neurotrophic factor (BDNF) is widely expressed in the central nervous system and is necessary for the survival of dopaminergic neurons in substantia nigra. G196A, a common polymorphism of the BDNF gene, not only affects cognitive and motor processes, but also is associated with various psychiatric disorders. We evaluated whether G196A polymorphism is associated with PD and/or modifies clinical manifestations in PD patients.
  
  
  METHODS
  We included 193 PD patients and 300 control subjects. G196A polymorphism was screened by restriction fragment length polymorphism analysis. Clinical features of each patient were examined in detail. The possible association between genotype and clinical characteristics were determined by bivariate and multivariate analyses.
  
  
  RESULTS
  The distribution of G196A allele and genotype frequency was similar between PD and control subjects. Clinical characteristics, including Hoehn-Yahr stage, motor symptoms, non-motor symptoms (depression, cognitive dysfunction, psychiatric dysfunctions, and sleep behavior disorder), and dyskinesias, were not associated with this polymorphism.
  
  
  CONCLUSIONS
  G196A polymorphism is not a risk factor for PD and does not seem to modify clinical features in PD patients studied here.
authors.affiliation: Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Spain.
authors.forename: L
authors.initials: L
authors.lastname: Gao
authors.forename: F J
authors.initials: FJ
authors.lastname: Díaz-Corrales
authors.forename: F
authors.initials: F
authors.lastname: Carrillo
authors.forename: J
authors.initials: J
authors.lastname: Díaz-Martín
authors.forename: M T
authors.initials: MT
authors.lastname: Caceres-Redondo
authors.forename: M
authors.initials: M
authors.lastname: Carballo
authors.forename: A
authors.initials: A
authors.lastname: Palomino
authors.forename: J
authors.initials: J
authors.lastname: López-Barneo
authors.forename: P
authors.initials: P
authors.lastname: Mir
mesh_terms: D000368:Aged; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D016022:Case-Control Studies; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010300:Parkinson Disease / Q000235:genetics* / Q000503:physiopathology*; D012150:Polymorphism, Restriction Fragment Length
chemical_list: D019208:Brain-Derived Neurotrophic Factor