title: Association of a polymorphism in intron 13 of the monoamine oxidase B gene with Parkinson disease.
abstract: Monoamine oxidase B (MAO-B) is an enzyme that has relevance for Parkinson disease (PD) because of its roles in catabolizing dopamine and potentially activating exogenous neurotoxicants. A polymorphism of the gene encoding MAO-B has been identified as a single base change (A or G) in intron 13 of the X chromosome. The A allele was previously associated with an approximately twofold risk of PD. The present study compared A and G allele frequencies between newly diagnosed idiopathic PD cases and a control group free of neurodegenerative diseases. All study subjects were Caucasian. Cases were 37 men and 25 women, age 37-80 years; controls were 50 men and 29 women, age 45-82 years. MAO-B genotype was determined by the allele-specific polymerase chain reaction on DNA extracted from peripheral lymphocytes. In complete contrast to previous studies, elevated risks were detected with the G allele. The age-adjusted odds ratio for the G allele in males was 1.87 ((95% confidence interval) 0.78-4.47). Among females the age-adjusted odds ratios were 5.00 ((95% confidence interval) 1.13-22.1) for the GA genotype and 5.60 ((95% confidence interval) 1.01-30.9) for the GG genotype. These findings, although of limited statistical precision, suggest that the G allele of this MAO-B polymorphism may relate to PD risk.
authors.affiliation: Department of Environmental Health, University of Washington, Seattle, Washington 98195-7234, USA.
authors.forename: P
authors.initials: P
authors.lastname: Costa
authors.forename: H
authors.initials: H
authors.lastname: Checkoway
authors.forename: D
authors.initials: D
authors.lastname: Levy
authors.forename: T
authors.initials: T
authors.lastname: Smith-Weller
authors.forename: G M
authors.initials: GM
authors.lastname: Franklin
authors.forename: P D
authors.initials: PD
authors.lastname: Swanson
authors.forename: L G
authors.initials: LG
authors.lastname: Costa
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D005260:Female; D005838:Genotype; D006801:Humans; D007438:Introns; D008297:Male; D008875:Middle Aged; D008995:Monoamine Oxidase / Q000235:genetics*; D010300:Parkinson Disease / Q000201:enzymology / Q000235:genetics*; D011110:Polymorphism, Genetic
chemical_list: D008995:Monoamine Oxidase