TSHBgene defects cause isolated congenital central hypothyroidism due to impaired synthesis of the β-subunit of thyroid-stimulating hormone (TSH). The β-subunit confers biological specificity to TSH; loss-of-function variants result in biologically inactive or absent TSH despite an anatomically intact thyroid gland. Autosomal recessive inheritance is the norm; disease typically manifests in homozygotes or compound heterozygotes.
TSHB