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

The objective of this study was to explore the genetic association of myeloperoxidase (MPO) gene polymorphisms with risk of Alzheimer's disease (AD).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 χ2 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.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.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.