Hongying Hao1, Ming Shao2, Jing An3, Chushuang Chen1, Xiuli Feng4, Shu Xie4, Zhuqin Gu4, Piu Chan5. 1. Department of Neurology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China. 2. Department of Neurologic Rehabilitation, Rehabilitation Hospital of Sichuan Province, Chengdu, China. Electronic address: yimshao@gmail.com. 3. Department of Neurobiology and Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China. 4. Chinese National Human Genome Center of Beijing(CHGB), Beijing, China. 5. 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.
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.
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 PDpatients 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 PDpatients who exhibited wearing-off compared to PDpatients without wearing-off (P < 0.05). A statistically higher frequency of the MAO-B (AG) genotype in PDpatients 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.