Study Of The Relationship Between Apolipoprotein E Gene Polymorphism And Cerebral Atherosclerosis In The Patients With Cerebral Infarction

ObjectiveTo investigate the relationship between apolipoprotein E gene polymorphism and cerebral atherosclerosis in the patients with cerebral Infarction. It will provide bases of effective prevention and treatment from these results in the high risk group of cerebral infarction during the early clinical.Methods1.Case selecting Patients with cerebral Infarction are selected stochastically in ShanXi Medical University No.1 Hospital from May,2009 to December,2009. All these add up to 245 cases.They are all Han people,without blood relationship. Their final diagnosis according to CT or MRA of head. Around 7:00 am in the second day of hospitalization,2ml fasting peripheral blood samples were collected into vacuum tubes containing anticoagulants ETDA from every patients, stored at-80 temperature. And to collect the age, gender, history of hypertension, smoking, drinking, to detect lipids, glycosylated hemoglobin, homocysteine information, etc. Use the high blood pressure value before hospitalize as the sufferer's common blood pressure. For the patients who sick with cardiogenic embolism, takayasu arteritis, or use the lipid-lowering drugs within the 2 weeks before hospitalize be removed.All selected patients were tested by MRA/CTA examination, carotid ultrasound and ApoE gene polymorphism.2. Groups According to the results of carotid ultrasound,MRA/CTA examination, all cases were divided into 2 groups:non-cerebral artery atherosclerosis group and cerebral artery atherosclerosis group. In order to distinguish the different effect of alleles s2 and s4, according to the PCR results,they were further divided into E2 (E2/2 and E2/3) group, E3 (E3/3) group and E4 (E3/4 and E4/4) group.3. Experimental methods To analyze the differences between patients with cerebral infarction atherosclerosis group and non-cerebral artery atherosclerosis group in ApoE polymorphism distribution by the method of amplification refractory mutation system polymerase chain reaction (ARMS-PCR), and analyze differences between the subgroup of ApoE genotype, and analyze the related risk factors between ApoE genotype of cerebral infarction, by means of removing the confounding factors.4. Statistical methods To establish a database with Microsoft Excel 2003, and to use SPSS 13.0 statistical package to analysis experimental data. Count data were showed by the frequency that differents count data between groups were analyzed by using chi-square test. Measurement data were showed by mean±standard deviation (X±S) and that measurement data in different groups were analyzed by using one-factor analysis of variance. The factors of the patients with cerebral infarction in cerebral atherosclerosis by logistic regression analysis. P<0.05 was significant statistically.Result1. Genotype and allelomorph Six genotypes were detected, which include E2/2, E2/3, E2/4, E3/3, E3/4, and E4/4. E3/3 was the major genotype in both cerebral atherosclerosis group and non-cerebral atherosclerosis group,accounting for 52.33% and 53.84%.In all selected patients, the cerebral atherosclerosis group occupied 21.22%, the cerebral atherosclerosis patients were 3.712 times than that non-cerebral atherosclerosis patients.According to the statistical analysis, there was significant difference in the genotypic frequency of E3/4 (P<0.05). In the group of non-cerebral atherosclerosis, allele frequencyε2,ε3, andε4 accounted for 14.42%,69.23%, and 16.35%, respectively. In the cerebral atherosclerosis group,ε2,ε3, andε4 accounted for 7.77%,70.47%, and 21.76%, respectively. On allele frequency distribution, there was no statistically significant in the two groups(p>0.05).2. The analysis of serum lipids in the two cerebral infarction groups In the two groups,the E4 subgroup had a apparently higher level of TC,LDL-C than those subgroup with E2,E3 (p<0.05),while the E3 subgroup had a significantly higher level of LDL-C than the E2 subgroup (p<0.05). Furthermore,in the cerebral atherosclerosis patients, the E2 subgroup had a apparently lower level of TC than the E4 subgroup (p<0.05).3. The influential factors of cerebral atherosclerosis in cerebral infarction subjects By using logistic regression, we analyzed possible influential factors of cerebral atherosclerosis in cerebral infarction subjects,including gender, age, hypertension, glycosylated hemoglobin, TC, TG, HDL-C, LDL-C,ApoE genotype, homocysteine, smoking, and drinking.These factors had been included in influential factors, such as age, hypertension, glycosylated hemoglobin, TC,LDL-C,ApoE genotype,and smoking history. With the older, the higher levels of glycosylated hemoglobin, total cholesterol and low density lipoprotein in the effluent, the greater possibility of cerebral atherosclerosis would happedd. On the ApoE genotype analysis shows, the patients with genotype E2/2 and E2/4 have a lower probability of brain atherosclerosis than the genotype E3/4 and E4/4. The incidence of cerebral atherosclerosis in hypertension patients were 9.675 times than that in patients with non-hypertension patients,and the incidence of cerebral atherosclerosis in smoking patients were 10.91 times than that in patients with non-smokers. Conclusion1. E 3/4 genotype is the risk factor of cerebral atherosclerosis in the patients with cerebral infarction.2. ApoEε4 carriers have a higher chance to increase serum levels of TC, and LDL-C.3. The influencing factor of cerebral atherosclerosis include age, glycosylated hemoglobin, TC, LDL-C, hypertension,ApoE genotype, and smoking history.4. On cerebral infarction patients,It is possible that ApoEε2 has protective effect to cerebral atherosclerosis,and ApoEε4 carrier has higher risk of cerebral atherosclerosis.