Introduction: Altered sensitivity against glucocorticoids is partly influenced by polymorphisms (SNP) of the glucocorticoid receptor gene (GR). The aim of the present study was to extend our earlier study by inclusion and evaluation the role of the BclI and A3669G polymorphisms of the GR in patients with hormonally inactive adrenal adenomas.
Description of methods: This is a retrospective, single-centre genetic association study The study included 99 patients with hormonally inactive (HI) adrenal adenomas discovered incidentally (incidentalomas) and 129 healthy controls. Hormonal evaluation of the hypothalamopituitaryadrenal axis, measurement of metabolic parameters was carried out in patients, and genetic analysis in all subjects. The BclI polymorphism was detected by allele specific PCR while the A3669G by Taqman allele discrimination assay.
Results: The prevalence of the BclI was lower in unilateral while the prevalence of the A3669G was lower in patients with bilateral HI than in healthy controls, (BclI: 21.8 vs 34.5%; A3669G: 10.8 vs 22.1% P<0.05). Patients who carried the BclI polymorphism had higher: systolic blood pressure, BMI, serum cholesterol level and ACTH level measured after methopyron test. The prevalence of obesity was also higher in BclI carriers, and this prevalence further increased when the A3669G SNP was present. Although lower prevalence of hyperlipidemia and plasma ACTH level was detected in the same group.
Conclusion: Our results confirm that behind the development of adrenal tumors especial in bilateral cases the polymorphic allele of the N363S and the wild type alleles of the BclI and A3669G represent genetic risk factors. Different mechanisms related to GR genetic variants alone or together may contribute to the morbidities found in these patients