Genetic abnormalities in parathyroid nodules of uremic patients.

The molecular pathway of autonomous growth of the parathyroid glands in uremic patients is poorly understood. We have analyzed 71 parathyroid lesions from 24 patients with refractory hyperparathyroidism for allelic loss at chromosomes 1, 3, 6, 9, 11, 12, 13, 15, and 17 and at the X chromosome. Microsatellite analysis was performed using 24 highly polymorphic markers. Deletions at chromosomes 1, 3, 6, 11, 12, and 13 and at the X chromosome were detected in only 10 of 67 nodules (15%). No allelic loss of the p16 and p53 tumor suppressor genes or the extracellular calcium receptor gene was found. The X-chromosome inactivation assay revealed a monoclonal pattern in 58% of hyperplastic nodules in females. Our results indicate monoclonal growth in the majority of hyperplastic nodules and suggest that some of these lesions might be considered precursors for adenoma development.