ESTROGEN-RECEPTOR GENE POLYMORPHISM IN POSTMENOPAUSAL PRIMARY HYPERPARATHYROIDISM

Background. Estrogen and its receptor play a key role in calcium homeo stasis, with implications in both the development and treatment of pri mary hyperparathyroidism. Methods, Leukocyte DIVA was isolated from 10 1 postmenopausal female patients with primary hyperparathyroidism and age-matched female control subjects (n = 101). Polymorphic estrogen re ceptor alleles denoted P/p and X/x were detected by polymerase chain r eaction and restriction digestion with Pvu II and Xba 1. Results. Alle lic prevalences were similar in the patients and control subjects. In contrast to normocalcemic control subjects, patients with primary hype rthyroidism homozygous for alleles P and X displayed less elevated ser um calcium concentrations (mean, 2.63 and 2.66 mmol/L) versus those wi th Pp and pp (2.72 mmol/L; p < 0.01) and Xx and xx (2.71; p < 0.05), r espectively, as well as trends for higher intact serum parathyroid hor mone values (p = 0.09). The PP genotype was accompanied by lower bone mineral density in the lumbar spine (p < 0.05). Conclusions. Estrogen receptor gene polymorphisms are presumably not directly involved in th e parathyroid tumorigenesis. However, they seem to interact with the e xtent of biochemical derangements of primary hyperthyroidism by possib le influences on both the peripheral action of parathyroid hormone and calcium regulation of its secretion.