Association of ACE gene haplotype with essential hypertension

Angiotensin-converting enzyme gene polymorphisms and hypertension in occupational noise exposure in Egypt

BACKGROUND

The gene-environment interaction in the pathogenesis of hypertension has not been extensively studied in occupational noise.

OBJECTIVES

The aim of this study was to determine the relationship between noise and hypertension in Egyptian workers, the interaction of angiotensin-converting enzyme (ACE) gene polymorphisms as modifiers, and the possible relationship between noise hearing impairment and hypertension.

METHODS

Study subjects were divided into two groups depending on noise exposure level. The control group (n = 161) was exposed to noise intensity <85 dB and the exposed group (n = 217) was exposed to noise intensity ≧85 dB. A polymerase chain reaction was used to differentiate the various genotypes of ACE insertion/deletion (I/D) and ACE G2350A.

RESULTS

Noise significantly increased the likelihood of hypertension. Carriers of the genotypes AG, GG, and DD were vulnerable to hypertension on noise exposure. No association between hypertension and hearing impairment or noise-induced hearing loss (NIHL) was found.

CONCLUSION

Our results support the association between ACE gene polymorphisms and occurrence of hypertension in noise-exposed workers.

Association between genetic polymorphisms of ACE & eNOS and diabetic nephropathy

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease, with multiple genetic and environmental factors involving in its etiology. ACE and eNOS gene were considered to have important roles in the development and progression of DN. In this study, a case-control study was carried out to investigate the effects of 7 SNPs in ACE gene and 2 SNPs in eNOS gene in the development of DN in Northern China.7 SNPs including A240T, A2350G, A5466C, A2215G, T3892C, C1237T and C3409T of ACE gene and 2 SNPs (G894T and T786C) of eNOS gene were genotyped by polymerase chain reaction restriction fragment length polymorphism method. 431 type 2 diabetic patients with nephropathy (cases) were compared to 420 type 2 diabetic patients without nephropathy (controls) in the study. Data were analyzed by SPSS 17.0 and HaploView software. The frequency distribution of A2350G, 4 haplotyps in ACE gene and G894T in eNOS gene were demonstrated to be different between case and control groups significantly. Whereas other SNPs and haplotypes had no differences in two cohorts. The results revealed that variations of ACE and eNOS gene had association with DN, which indicated ACE and eNOS gene may play an important role in pathogenesis of DN in Northern Chinese Han population.

Effect of ACE polymorphisms on the association between noise and hypertension in a Pakistani population

Introduction: This study investigates the effect of angiotensin converting enzyme (ACE) polymorphisms on the association between noise and hypertension.

Subjects and methods: A cross sectional study was conducted involving 385 male volunteers. In the control group 156 participants were exposed to a sound level of ≤80 dB; in the exposed group 229 individuals were exposed to a sound level ≥80 dB. Both groups were subdivided into categories on the basis of blood pressure. A polymerase chain reaction (PCR)-based strategy was used to differentiate the various genotypes of ACE ID and ACE G2350A. Association of noise with genotypes as modifiers was estimated after adjustment of data for age and body mass index.

Results: These showed the following odds ratios (OR) with 95% confidence interval (CI) indicating that noise is associated with hypertension in a Pakistani population (OR: 3.196; CI: 1.803–5.666). ACE ID and ACE G2350A polymorphism affects this association. ID (OR: 2.844: CI: 1.32–6.110) and DD allele carriers (OR: 4.487; CI: 1.549–12.99) were at increased risk of hypertension. GG (OR: 3.970; CI: 1.628–9.681) and GA (OR: 3.705; CI: 1.407–9.758) carriers were also at increased risk of hypertension associated with noise. However II and AA allele carriers were not found to be at increased risk of hypertension.

Conclusion: ACE ID polymorphism and ACE G2350A polymorphism modulates the effects of noise on blood pressure.