Aldosterone Synthase Gene Polymorphism Research Articles

Aldosterone synthase (CYP11B2) gene polymorphism and cerebral white matter hyperintensities.

The association between aldosterone synthase (CYP11B2) gene polymorphism and white matter hyperintensities seen on cerebral MRI was studied in a population-based sample of 829 individuals aged 63 to 75 years. The T allele was associated with the risk of severe white matter hyperintensities. Compared with the CC genotype, the adjusted OR for severe white matter hyperintensities was 4.61 (95% CI, 1.46 to 14.55) for the TT genotype and 2.45 (95% CI, 0.81 to 7.46) for the TC genotype in men. This association was independent of hypertension.

Aldosterone synthase gene polymorphisms in primary aldosteronism

Aldosterone synthase gene polymorphisms in primary aldosteronism

Evaluation of the Aldosterone Synthase (CYP11B2) Gene Polymorphism in Patients With Myocardial Infarction

Left ventricular remodeling after myocardial infarction involves activation of the renin-angiotensin-aldosterone system. Recently, the biallelic -344T/C polymorphism of the aldosterone synthase gene was associated with increased aldosterone levels, arterial hypertension, diastolic dysfunction, and left ventricular dilatation. We hypothesized that this polymorphism may also affect left ventricular geometry and function after myocardial infarction. By using a standardized questionnaire, as well as anthropometric and echocardiographic measurements, we thus studied 606 patients (533 men and 73 women) who had a myocardial infarction before the age of 60 years. The aldosterone synthase gene polymorphism was analyzed after polymerase chain reaction amplification and restriction enzyme digestion. The results demonstrated that there was no association of the aldosterone synthase gene polymorphism with echocardiographically determined left ventricular dimensions, wall thicknesses, or indexes of systolic or diastolic function. Furthermore, anthropometric data, including blood pressure levels, were balanced between the different genotypes. Finally, the allele frequency was similar for patients with myocardial infarction and a sample group from the normal population (n=1675). The data indicate that the allele status of the aldosterone synthase gene polymorphism is not useful for the identification of patients with myocardial infarction who have impaired left ventricular function or unfavorable remodeling.

Associations between aldosterone synthase gene polymorphism and the adrenocortical function in males.

Two diallelic polymorphisms, one in the transcriptional regulatory region (promoter) and the other in the second intron, have been identified in the aldosterone synthase (CYP11B2) gene encoding aldosterone synthase, the enzyme catalysing the last steps of aldosterone biosynthesis. We have examined the associations between these genetic variations and adrenocortical function in a cohort of Finnish males. A cross-sectional study. Helsinki University Central Hospital, Finland. Ninety-two males aged 30-55 years. Basal adrenocortical function was assessed by measuring urinary excretion of aldosterone and cortisol. Functional activity was determined by responses of several adrenal steroids to dexamethasone suppression followed by ACTH stimulation. Polymerase chain reactions were used to identify the polymorphisms in the CYP11B2 gene. The -344TT genotype group in the CYP11B2 promoter had lower systolic blood pressures (P=0.039), but higher urinary aldosterone excretion (P=0.016), and 11-deoxycortisol responses to ACTH stimulation (P=0.021) than the-344CC genotype group. Urinary aldosterone excretion (P=0.033), 11-deoxycortisol (P=0.026), and aldosterone (P=0.013) responses to ACTH were higher in the intron 2 conversion than the nonconversion genotype groups. Polymorphisms in or near the aldosterone synthase gene are associated with variations in aldosterone and 11-deoxycortisol production in males. This may modulate the activity of the renin-angiotensin system and thereby contribute to blood pressure regulation.

Associations between human aldosterone synthase (CYP11B2) gene polymorphisms and left ventricular size, mass, and function.

Aldosterone has direct and indirect effects on the heart, and genetic variations in aldosterone synthesis could therefore influence cardiac structure and function. Such variations might be associated with polymorphisms in the gene encoding aldosterone synthase (CYP11B2), the enzyme catalyzing the last steps of aldosterone biosynthesis. A Finnish population sample of 84 persons (44 women) aged 36 to 37 years was studied by M-mode and Doppler echocardiography to assess left ventricular size, mass, and function. Subjects were genotyped through the use of the polymerase chain reaction for two diallelic polymorphisms in CYP11B2: one in the transcriptional regulatory region (promoter) and the other in the second intron. In multiple regression analyses, the CYP11B2 promoter genotype predicted statistically significant variations in left ventricular end-diastolic diameter (beta=.40, P<.0001), end-systolic diameter (beta=.33, P=.0009), and mass (beta=.17, P=.023). These effects were independent of potentially confounding factors, including sex, body size, blood pressure, physical activity, smoking, and ethanol consumption. Genotype groups also differed in a measure of left ventricular diastolic function, the heart rate-adjusted atrial filling fraction (P=.018). Increased dietary salt, which is known to predict increased left ventricular mass, had this effect only in association with certain CYP11B2 genotypes (P<.001). Genetic variations in or near the aldosterone synthase (CYP11B2) gene strongly affect left ventricular size and mass in young adults free of clinical heart disease. These polymorphisms may also influence the response of the left ventricle to increases in dietary salt.