title: DRD2 haplotype is associated with dyskinesia induced by levodopa therapy in Parkinson's disease patients.
abstract: OBJECTIVE
  Dyskinesia and motor fluctuation are frequent and serious complications of chronic levodopa therapy in patients with Parkinson's disease. Since genetic factors could play a role in determining the occurrence of these problems, the aim of the present study was to investigate whether possible functional polymorphisms among DRD2 and ANKK1 genes are associated with the risk of developing dyskinesia and motor fluctuations in Parkinson's disease patients.
  
  
  METHODS
  One hundred and ninety nine patients in treatment with levodopa were genotyped for the -141CIns/Del, rs2283265, rs1076560, C957T, TaqIA and rs2734849 polymorphisms at the DRD2/ANKK1 gene region.
  
  
  RESULTS
  Carriers of the TTCTA haplotype showed an increased risk for the presence of dyskinesia (p = 0.007; 1.538 [95% CI: 1.126-2.101]).
  
  
  CONCLUSIONS
  Our data suggest an influence of the DRD2/ANKK1 gene region on levodopa-induced dyskinesia.
authors.affiliation: Departamento de Genética, Instituto de Biociências, Universidade Federal do Rio Grande do Sul, Caixa Postal 15053, 91501-970 Porto Alegre, RS, Brazil.
authors.forename: Mariana
authors.initials: M
authors.lastname: Rieck
authors.forename: Artur F
authors.initials: AF
authors.lastname: Schumacher-Schuh
authors.forename: Vivian
authors.initials: V
authors.lastname: Altmann
authors.forename: Carolina Lm
authors.initials: CL
authors.lastname: Francisconi
authors.forename: Paulo Tb
authors.initials: PT
authors.lastname: Fagundes
authors.forename: Thaís L
authors.initials: TL
authors.lastname: Monte
authors.forename: Sidia M
authors.initials: SM
authors.lastname: Callegari-Jacques
authors.forename: Carlos Rm
authors.initials: CR
authors.lastname: Rieder
authors.forename: Mara H
authors.initials: MH
authors.lastname: Hutz
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004409:Dyskinesia, Drug-Induced / Q000201:enzymology / Q000209:etiology* / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D006239:Haplotypes; D006801:Humans; D007980:Levodopa / Q000009:adverse effects* / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000188:drug therapy* / Q000235:genetics*; D011110:Polymorphism, Genetic; D017346:Protein Serine-Threonine Kinases / Q000235:genetics; D017448:Receptors, Dopamine D2 / Q000235:genetics*
chemical_list: C581293:DRD2 protein, human; D017448:Receptors, Dopamine D2; D007980:Levodopa; C489948:ANKK1 protein, human; D017346:Protein Serine-Threonine Kinases