Autoantibodies to thyroglobulin are antibodies to the iodized protein (thyroglobulin) from which thyroid hormones are formed. Their presence may indicate disorders of the thyroid gland, in particular, autoimmune processes.

In patients with suspected autoimmune thyroiditis, ATTG is detected in 70-80% of such cases, those with diffuse toxic goiter in 30-40% of cases also have ATTG, and people with non-autoimmune thyroid diseases in 10-15% of cases may have an increase in ATTG levels.