The association of MPO gene promoter polymorphisms with Alzheimer’s disease risk in Chinese Han population

// Wenzhen Ji 1, * and Yu Zhang 2, * 1 Department of Neurology, Tianjin Huanhu Hospital, Tianjin Key Laboratory of Cerebrovascular and Neurodegenerative Diseases, Tianjin 300000, China 2 Division of Medical Affairs, Tianjin Huanhu Hospital, Tianjin Key Laboratory of Cerebrovascular and Neurodegenerative Diseases, Tianjin 300000, China * Co-first author: Wenzhen Ji and Yu Zhang Correspondence to: Wenzhen Ji, email: oiwdfg@yeah.net Yu Zhang, email: io23rdgd@126.com Keywords: Alzheimer’s disease; MPO ; polymorphisms; plasma concentration Received: June 22, 2017     Accepted: September 20, 2017     Published: November 06, 2017 ABSTRACT Aim: The objective of this study was to explore the genetic association of myeloperoxidase ( MPO ) gene polymorphisms with risk of Alzheimer’s disease (AD). Methods: Blood samples were collected from 116 AD patients and 134 age and gender matched healthy individuals. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was utilized to confirm MPO polymorphisms in promoter region. Plasma concentration of MPO was detected by enzyme-linked immuno sorbent assay. Genotype distributions of MPO polymorphisms were compared by χ 2 test between the two groups. The status of linkage disequilibrium between MPO two polymorphisms was detected using Haploview. MPO concentrations were analyzed by non-parametric test. Results: MPO rs2333227 polymorphism was positively associated with AD risk, especially under the AA+GA vs. GG and A vs. G genetic models ( P =0.042, OR=1.719, 95%CI=1.017-2.906; P =0.041, OR=1.582, 95%CI=1.016-2.463). While, rs34097845 polymorphism significantly decreased the risk of AD, particularly GA and AA+GA genotypes ( P =0.048, OR=0.555, 95%CI=0.308-0.998; P =0.042, OR=0.552, 95%CI=0.310-0.983). In addition, rs2333227 genotypes affected the plasma concentration of MPO. But for rs34097845 polymorphism, only GA genotype exhibited significant association with MPO concentration. Conclusion: Polymorphisms in the promoter region of MPO distinctly contribute to AD risk possibly through regulating MPO concentration. Present results should be confirmed by further studies.