Point mutations of thyreotropin receptor as main cause of autonomously functioning thyroid nodules: Experiences in Styrian patients

Autonomously functioning thyroid nodules are frequently associated with mut ations of the thyrotropin receptor. We analyzed a part of exon 10 of the th yrotropin receptor gene (base pairs 1762-1976) by direct sequencing and fou nd missense mutations in 5 of 14 cases (codons 629, 631, 632, 633). Histolo gically, 3 of the 14 nodules were adenomas whereas 11 were hyperplasias. No dules with mutations did not show significant differences from nodules with out mutations with respect to age, histology, size, additional (non-functio nal) nodules and clinical symptomatology. Our results confirm that thyrotro pin receptor mutations are involved in the development of autonomously func tioning thyroid nodules. In this context, the terms hyperplasia and neoplas ia should be reevaluated.