Korean J Pediatr.  2005 Mar;48(3):337-341.

Hyperthyroidism Caused by a Mutation in the Thyrotropin Receptor Gene in Two Brothers

• Kim JH
• Lee SS
• Lim JS
• Shin CH
• Yang SW

Abstract

Thyrotropin receptor(TSHR) mutations must be considered when congenital hyperthyroidism has persisted, but there has been no evidence for autoimmunity. TSHR mutations leading to constitutive activation of the thyroid gland were identified as the molecular cause of autosomal dominant nonautoimmune hyperthyroidism and sporadic congenital hyperthyroidism. We report two cases of hyperthyroidism caused by germline TSHR mutation who presented with exessive sweating and no evidence of autoimmune thyroid disease. They were brothers and their mother had undergone thyroidectomy because of hyperthyroidism. Direct sequencing of the polymerase chain reaction-amplified exon 10 of the TSHR genomic DNA revealed a transition of GCT to GTT, resulting in an exchange of alanine 627 to valine in the patients and their mother. This might be a novel mutation or polymorphism, but we did not perform any functional gene study. But considering the clinical profiles, we can conclude that hyperthyroidism of these two brothers might come from the point mutation described above.

Keyword

Hyperthyroidism; Thyrotropin receptor mutation

MeSH Terms

Alanine
Autoimmunity
DNA
Exons
Humans
Hyperthyroidism*
Mothers
Point Mutation
Receptors, Thyrotropin*
Siblings*
Sweat
Sweating
Thyroid Diseases
Thyroid Gland
Thyroidectomy
Thyrotropin*
Valine
Alanine
DNA
Receptors, Thyrotropin
Thyrotropin
Valine