Abstract: Objective To investigate the possible relationship between the methylenetetrahydrofolate reductase(MTHFR) gene C677T polymorphism and renal damage caused by essential hypertension(EH) and renal parenchymal hypertension. Methods The technology of polymerase chain reaction-restriction fragment length polymorphism(PCR-RELP) was used to detect the distribution of frequencies of MTHFR gene C677T mutation in healthy controls,EH patients with normal renal function,EH patients with renal failure and renal parenchymal hypertension.Results The systolic and diastolic blood pressures in EH patients with renal failure and renal parenchymal hypertension were both significantly higher than that in EH patients withnormalrenal function(P<0.05).The frequency of MTHFR T allele in EH patients with renal failure was significantly higher than that in healthy controls and in EH patients with normal renal function(42.1% vs 18.3% and 19.2%,P<0.05).There was no difference in other two groups(P>0.05).There was also no difference in the distribution of the frequencies of MTHFR C/C,(C/T) and T/T genotypes in any two groups.Conclusion MTHFR T allele is probably one of the predisposing factors for EH patients associated with chronic renal failure in north Hans.

Key words: methylenetetrahydrofolate reductase gene, essential hypertension, renal parenchymal hypertension