NON-AUTOIMME HYPERTHYROIDISM

ANALYSIS OF EXON10 OF THE TSHR GENE

Non-autoimmune hyperthyroidism is transmitted as an autosomal dominant trait and is characterised by the presence and signs of hyperthyroidism and diffuse goiter (low TSH levels and elevated T3 and T4 levels) without evidence of an autoimmune etiology.  The age of onset is highly variable as is the size of the goiter, which can be minimal or absent in young patients.

Germline gain-of-function variants in the TSHR gene are cause non-autoimmune hyperthyroidism.  Approximately 95% of cases have a variant in exon 10 of the TSHR gene (Hebrant et al. 2010 Eur J Endocrinol 164:1-9).

Loss-of-function variants in the TSHR gene cause Thyroid Stimulating Hormone (TSH) resistance (Congenital Hypothyroidism), characterised by elevated TSH levels and decreased or normal thyroid hormone (T3 and T4) levels. Disease-causing variants are located throughout the TSHR gene (Persani et al. 2010 Mol Cell Endocrinol 322:72-82).

The laboratory participates in the European Molecular Genetics Quality Network (EMQN) sequencing scheme.