Identification of eight new mutations in the c-erbA beta gene of patients with resistance to thyroid hormone

Resistance to thyroid hormone (RTH) is a rare genetic disorder, usually ass ociated with different mutations in the c-erbA beta gene that encodes the b eta type receptor of thyroid hormone (TR beta). It is characterized by elev ated serum thyroid hormone and inappropriate TSH secretion. The numerous mu tations so far detected are clustered in three hot spot areas in the ligand binding domain of TR beta. In the context of a national survey we have det ected 16 different mutations in the c-erbA beta gene, in 22 families presen ting with RTH. Eight of these mutations had not been described previously. Two are located in an area not known to harbor naturally occuring mutations . This observation could lead to define a fourth cluster of mutations in th e c-erbA beta gene.