Thyroglobulin
Synonym(s)
DefinitionThis section has been translated automatically.
Thyroglobulin (TG) is a dimeric glycoprotein with a molecular mass of about 660 kDa synthesized and secreted by the epithelial cells of the thyroid (thyroocytes) under the influence of thyrotropin (TSH). Thyroglobulin is the main component of the colloid of the thyroid gland. The thyroid hormone synthesis of thyroxine and triiodothyronine as well as of biologically little or non-active iodothyronines takes place from thyroglobulin by proteolysis. In the synthesis of thyroid homones, the iodine atoms are bound to the tyrosine components of thyroglobulin (iodination).
Thyroglobin is not only present in the thyroid follicles, but also in small amounts in the serum of healthy individuals (reference range: <50ng/ml)Tg is below the detection limit (<1ng/ml) in thyroablative therapy of thyroid carcinoma. A renewed increase in the value indicates metastasis.
Elevated antibodies against thyroglobulin(Tg-AK/TAK) indicate an autoimmune disease of the thyroid gland such as chronic lymphocytic thyroiditis (Hashimoto's thyroiditis).
General informationThis section has been translated automatically.
Indications for the determination of Tg:
- tumour marker in different/netastatic thyroid carcinoma
- Follow-up after ablative therapy of differentiated thyroid carcinoma
- Marker for hyperthyroidism factitia (TG suppressed)
Note(s)This section has been translated automatically.
Mutations of the thyroglobin gene, which is located on chromosome 8q24, can lead to a goiter.