The Study On The Association Of Apolipoprotein E Gene Polymorphism With Alzheimer’s Disease And Mild Cognitive Impairment Among Han Elderly People In Jiangxi

Objective:By studying apolipoprotein E (ApoE) allele distribution in Jiangxi Han elderlypatients with Alzheimer’s disease (AD), mild cognitive impairment (MCI) patientsand normal control subjects to explore the association of Apolipoprotein E GenePolymorphism with AD and MCI among Han elderly people in Jiangxi province.Methods:110cases of patients with MCI and54cases of patients with sporadicAlzheimer’s disease as research groups were selected from psychosomatic medicineoutpatient of the First Affiliated Hospital of Nanchang University, February2012toJuly.114unrelated health examination people as normal control subjects matched withage, gender, ethnic, educational level, their background etc.in the same period.Allenrolled subjects agreed to join this study.2ml fasting peripheral blood were extractedfrom all of them and EDTA-Na2anticoagulant disposed.Using blood genomicminiprep kit extracted sample DNA,PCR amplified the ApoE gene sequence,anddirect sequencing method identified each sample ApoE gene alleles andgenotypes.Finally,we used Microsoft Excel and SPPS13.0statistic software toanalyze relevant statistical indicators,calculate the three groups of ApoE allele andgenotype frequencies.using Hardy-Weinberg genetic equilibrium tested goodness offit,enumeration data were analyzed by χ2test or Fisher’s exact test,multiple sets ofmeasurement data were analyzed by one-factor analysis of variance (ANOVA) test.Significance level α=0.05, two-sided test.Results:1.ApoE allele frequencies and genotype frequencies of AD patient group,MCIpatient group and normal control group are all in line with H-W genetic equilibrium(p>0.05).2.Among AD patient group,MCI patient group and normal control group,ApoEε3/3homozygote genotype had the highest rate, ε3/4and ε2/3genotype second, ε2/4,ε4/4and ε2/2genotype least; comparison between ApoE gene genotype in AD group,MCI group and normal control group,the differences were not statisticallysignificant (p>0.05).3.ApoEε4gene frequency of AD patient group was14.81%（16/108）,comparednormal control group7.89%（18/228）with a statistically significant difference (χ2=3.86,p<0.05);ApoEε4gene frequency of MCI patient group was14.09%（31/220）,compared normal control group also with a statistically significantdifference（χ2=4.41,p<0.05); ApoEε4gene frequency’s difference between AD groupand MCI group was not significant(p>0.05). ApoEε2,ε3allele frequencies of thethree groups,pairwise compared,the differences were not statistically significant (p>0.05).4.Compared with the normal control group, ApoE epsilon4allele increased therisk of AD onset（OR=2.029，p=0.049）;the association between epsilon2or epsilon3allele and the onset of AD was not significant.Similarly, ApoE epsilon4allele waspositively associated with the onset of MCI（OR=1.914，p=0.036）;epsilon2,epsilon3allele was not related to the incidence of MCI.While,there was no significantcorrelation between the ApoE epsilon4allele of AD onset and MCI onset.Conclusions:1.The study confirmed that allele ε4of the ApoE gene was a pathogenic riskfactor for sporadic AD.2.Among Han elderly people in Jiangxi province,MCI prevalence is alsoassociated with ApoE gene polymorphism and the ApoE ε4allele could be apathogenic risk factor for MCI.3.Carriers with the ApoE epsilon4allele risked2.029times of AD onset thannon-carriers,while carriers with the ApoE epsilon4allele risked1.914times of MCIonset than non-carriers.