Study On The Association Of Gene Ploymorphism Of N^5,10-Methylenetetrahydrofolate Reductase （MTHFR） And Essential Hypertension Between Hui And Han People In Ningxia

Objective To study distributional characteristics of gene ploymorphism ofN5,10-methylenetetrahydrofolate reductase (MTHFR) between Hui and Han nationalities inNingxia and the relationship between the polymorphism and essential hypertension.Methods The study was performed in146Hui patients and155Han patients withessential hypertensive(EH) and was performed in112Hui peoples and140Han peoples withnormal tensive(NT). MTHFR gene polymorphism was detected by polymerase chainreaction-restriction fragment length polymorphism (PCR-RFLP). We collected generalinformation from all subjects，including sex，age，nation and so on. We also measured bloodurea nitrogen(BUN)，creatinine(Cr)，fasting serum glucose，uric acid，triglyceride(TG)，totalcholesterol(TC)，high-density lipoprotein cholesterol(HDL-C) and low-density lipoproteincholesterol(LDL-C) in all subject. All statistical analyses were performed using SPSS17.0statistical analysis software. The Hardy-Weinberg equilibrium of ploymorphism was assessedby Pearson’s χ~2test. Differences in the frequencies of alleles and genotypes were alsoanalyzed by Pearson’s χ~2test. Differences of measurement data between two groups werecompared by t-test. If equal variances not assumed，differences of measurement data betweentwo groups were compared by t，-test. Differences of measurement data among many groupswere compared by the single-factor analysis of variance，the mean differences between two ofthe various samples were compared with LSD-t test. The risk factors，for example genotypes， were analyzed by binary stepwise logistic regression and odds ratio(OR) and95%confidenceinterval(CI)were calculated.Results (1) The distribution of genotypes in the Hui and Han people were in line withHardy-Weinberg genetic equilibrium equation(P>0.05).(2) The frequencies of TT genotype and T allele inHui patients with hypertension were of no difference with those in Han patients(P>0.05). There were alsono significant differences between Hui NT group and Han NT group(P>0.05). The frequencies of677TTgenotype and T allele in Hui patients with EH were higher than those of Hui NT group(P<0.05). Thefrequencies of677TT genotype had no statistics difference between Han EH group and Han NT group(P>0.05). But comparing with allele carrierCT+TT genotype frequencies，statistics difference had beenshowed between two groups((P<0.01).The frequencies of CT+TT genotype and T allele in Han patientswith EH were both higher than those of control(P<0.05).(3) The comparative results of clinical datashowed that systolic blood pressure，diastolic blood pressure，pulse pressure and mean arterial pressure hadsignificant difference among three genotype groups(P<0.05). The mean differences between two of thevarious comparison showed that systolic blood pressure，diastolic blood pressure and mean arterial pressurein CT genotype group were higher than those of CC genotype group，there was significant differencebetween two groups(P<0.05). Systolic blood pressure，pulse pressure and mean arterial pressure in TTgenotype group were higher than those of CC genotype group，there was significant difference between twogroups(P<0.05). Blood pressure had no significant difference between CT genotype group and TT genotypegroup(P>0.05).(4) Binary stepwise logistic regression analysis showed that after adjusting otherconfounding factors，CT and TT genotypes of MTHFR gene were significantly associated with essentialhypertension（CT：OR1.952，95%CI1.263~3.016，P=0.003；TT：OR2.433，95%CI1.371~4.318，P=0.002）. CT genetype，TT genetype，age，body mass index，blood urea nitrogen(BUN)，furic acid，triglyceride(TG) and low-density lipoprotein cholesterol(LDL-C) were risk factors for essentialhypertension.Conclusions There does not exist racial difference between Hui and Han nationalitieswith MTHFR C677T gene polymorphism. The polymorphism has a correlation with EH between Hui and Han nationalities in Ningxia. T allele maybe a susceptible gene for EH inNingxia people.