Angiotensin-converting enzyme gene polymorphism in patients with Essential hypertension

Abstract

Several genetic investigations have been attempted to elucidate the association of angiotensin-converting enzyme (ACE) gene polymorphism and essential hypertension. This study was conducted to investigate the frequency of ACE gene insertion/deletion (I/D) polymorphism in patients with essential hypertension (EH). The study included one hundred patients with essential hypertension and seventy age and sex matched healthy individuals as a control group. The patients and control group were subjected to routine investigations, assay of serum cholesterol, triglycerides, high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-cholesterol (LDL-C) and assay of ACE gene I/D polymorphism using real-time polymerase chain reaction (PCR). The results of the study showed that the frequency of DD,ID and II genotypes were 42%, 44% and 14 % respectively in hypertensive group and 30%, 50% and 14 % respectively in control group with significantly higher frequency of DD genotype in patients as compared to the control group (p<0.05). There was a significant association between DD genotype and hypertension, as there was significant increase in both systolic and diastolic blood pressure in patients with DD genotype as compared to other genotypes. Serum cholesterol , HDL-C and LDL –C levels showed significant increase in patients as compared to the control group (P <0.001, P <0.001 and P <0.001: respectively ) Also, serum Cholesterol and LDL-C levels showed significant increase in patients with DD and ID genotypes as compared to II genotype , while triglycerides and HDL-C didn’t show differences between the three genotypes. It was concluded that the DD genotype of ACE gene showed significantly higher frequency among patients with essential hypertension as compared to the normal subjects and that DD genotype was associated with significantly higher blood pressure as compared to ID and II genotypes. Also, DD genotype was associated with significantly higher serum cholesterol and LDL-C as compared to II genotype. This polymorphism in the ACE gene may contribute to the pathogenesis and severity of essential hypertension and may help in selection of anti-hypertensive drugs.