NCIt definition : Two ERBA proto-oncogenes located on separate chromosomes, encode ERBA alpha and ERBA
beta, which are thyroid hormone receptors in the nucleus and bind DNA to activate
transcription. Multiple thyroid hormone receptor (THR) genes may be encoded in the
human genome and perhaps as many as five loci with varying expression in different
tissues and stages of development. The ERBA1 gene at 17q11.2 encodes ERBA alpha-1,
ERBA alpha-2, and ERBA alpha-3, each produced by alternative splicing. All ERBA1 transcripts
are coordinately expressed. The ERBA2 gene at 3p24.3 encodes ERBA beta-1 and a neighboring
gene encodes ERBA beta-2. The TH receptor expressed in the mammalian CNS and most
other tissues (except liver) is encoded by ERBA1. The receptor present in liver (the
major TH-responsive organ) and some other tissues is encoded by ERBA2. Point mutations
in the ERBA2 gene are associated with generalized resistance to thyroid hormone.;