Endocrine Abstracts

Background: The enzymes 11beta-hydroxylase and aldosterone synthase are key control steps in regulation of cortisol and aldosterone synthesis. We have previously reported that polymorphic variation of the gene encoding aldosterone synthase (CYP11B2) is associated with altered efficiency of 11b-hydroxylation of the precursor of cortisol, deoxycortisol. In order to examine this relationship in greater detail, we have studied the pattern of steroid precursor metabolite excretion ...

Aldosterone synthase (CYP11B2) and 11beta-hydroxylase (CYP11B1) genes are highly homologous in their coding regions (95%), lie in tandem approximately 40kb apart in human chromosome 8, and may have arisen from gene duplication. The pattern of linkage disequilibrium (LD) of this region in a population is determined not only by the distribution of recombination events but also by demographic factors determining the amount of random genetic drift. There is suggestiv...

Background: Cortisol availability to target tissues represents a complex interplay of synthesis, secretion, metabolism and excretion. A number of these processes are regulated by enzymes that are encoded by genes that are key candidates in determining the metabolic and cardiovascular phenotype in man. Measurement of a range of corticosteroid metabolites allows the activity of these enzymes to be inferred. We have studied the pattern of cortisol metabolite excretion in a large ...

Recent studies in non-hypertensive patients have shown aldosterone renin ratio (ARR) to be heritable and associated with increased risk of blood pressure (BP) elevation. Furthermore, a raised ARR is present in 10% of hypertensive patients although the precise significance of this is unclear. The magnitude of heritability of ARR will indicate the influence of genetic determination of the phenotype. In this study, we estimated the heritabilities of the components of ARR and the ...