A new polymorphic restriction site in the human 11 beta-hydroxysteroid dehydrogenase type 2 gene

Abstract

The 11 beta-hydroxysteroid dehydrogenase type II enzyme (11 beta HSD2) inactivates glucocorticoids in the kidney and thus prevents glucocorticoids from occupying the non-selective mineralocorticoid receptor in epithelial tissues. Mutations in the HSD11B2 gene have been found to cause the syndrome of apparent mineralocorticoid excess, a rare autosomal recessive disease characterized by severe hypertension. Thus, this locus could also be an ideal candidate involved in the etiology of primary hypertension. We identified a polymorphism in exon 3 characterized by a GAG to GAA transition at codon 178, with the loss of an Alu I restriction site and analysed it in an association study using end-stage renal disease patients, diabetic or essential hypertensive patients and control subjects. Two-hundred and eighty nine subjects and patients were analysed; the genotype was determined by amplification of genomic DNA and subsequent digestion with Alu I restriction enzyme. The prevalence of the Alu I allele was 8.6% in healthy control subjects (n = 116). This prevalence was lower (chi 2 P = 0.035 vs. controls) than the 18.0% in a group of renal transplant patients (n = 61). The corresponding values for patients with diabetes mellitus (n = 25), hypertension (n = 41) and patients on dialysis (n = 46) were 4.0%, 4.8% and 4.3%, respectively. There was no correlation between blood pressure and the marker in non-ESRD subjects. These data indicate the presence of a polymorphic marker in exon 3 of the HSD11B2 gene; this marker is associated with end-stage renal disease but not with essential hypertension in humans.