title: Association of Catechol-O-Methyltransferase and monoamine oxidase B gene polymorphisms with motor complications in parkinson's disease in a Chinese population.
abstract: BACKGROUND
  Catechol-O-Methyltransferase (COMT) and Monoamine oxidase B (MAO-B) are the main enzymes that metabolize dopamine in the brain. The polymorphisms of the COMT gene and MAO-B gene are associated with high, intermediate and low levels of activity. This may influence the prevalence of motor complications in Parkinson's Disease (PD).
  
  
  METHODS
  The study enrolled 1087 Chinese PD patients throughout the country. Sanger dideoxynucleotide chain termination methods were used for COMT and MAO-B genotyping. The researchers compared the association between presence of motor complications and COMT and MAO-B gene polymorphisms, both separately and in combination.
  
  
  RESULTS
  Comparison of the allele frequencies revealed that COMT (GG) was significantly more common among PD patients who exhibited wearing-off compared to PD patients without wearing-off (P < 0.05). A statistically higher frequency of the MAO-B (AG) genotype in PD patients with dyskinesias was found (P < 0.05). Although these differences were not significant after Bonferroni's correction. The combined haplotype of the MAO-B and COMT showed no increase (p < 0.05) in the risk of wearing-off and dyskinesias.
  
  
  CONCLUSIONS
  Our findings suggest that polymorphisms in COMT and MAO-B may increase the risk of wearing-off and dyskinesias. COMT (GG) genotype may be the risk factor of wearing-off. While MAO-B (AG) genotype may be the risk factor of dyskinesias.
authors.affiliation: Department of Neurology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
authors.forename: Hongying
authors.initials: H
authors.lastname: Hao
authors.affiliation: Department of Neurologic Rehabilitation, Rehabilitation Hospital of Sichuan Province, Chengdu, China. Electronic address: yimshao@gmail.com.
authors.forename: Ming
authors.initials: M
authors.lastname: Shao
authors.affiliation: Department of Neurobiology and Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China.
authors.forename: Jing
authors.initials: J
authors.lastname: An
authors.affiliation: Department of Neurology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
authors.forename: Chushuang
authors.initials: C
authors.lastname: Chen
authors.affiliation: Chinese National Human Genome Center of Beijing(CHGB), Beijing, China.
authors.forename: Xiuli
authors.initials: X
authors.lastname: Feng
authors.affiliation: Chinese National Human Genome Center of Beijing(CHGB), Beijing, China.
authors.forename: Shu
authors.initials: S
authors.lastname: Xie
authors.affiliation: Chinese National Human Genome Center of Beijing(CHGB), Beijing, China.
authors.forename: Zhuqin
authors.initials: Z
authors.lastname: Gu
authors.affiliation: Department of Neurobiology and Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China; Beijing Key Laboratory on Parkinson's Disease and Beijing Institute for Brain Disorders, Beijing, China.
authors.forename: Piu
authors.initials: P
authors.lastname: Chan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People / Q000235:genetics; D002394:Catechol O-Methyltransferase / Q000235:genetics*; D020820:Dyskinesias / Q000235:genetics / Q000503:physiopathology; D005260:Female; D005787:Gene Frequency; D056726:Genetic Association Studies; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D008995:Monoamine Oxidase / Q000235:genetics*; D009043:Motor Activity / Q000235:genetics*; D010300:Parkinson Disease / Q000235:genetics* / Q000503:physiopathology*; D011110:Polymorphism, Genetic / Q000235:genetics*; D012720:Severity of Illness Index
chemical_list: D008995:Monoamine Oxidase; C588010:COMT protein, human; D002394:Catechol O-Methyltransferase
keywords: COMT; Dyskinesias; MAO-B; Parkinson's disease; Wearing-off