[The incidence of antithyroid antibodies in relatives of patients with thyroid disorders (author's transl)].

In order to elucidate a predisposition for so-called autoimmune thyroid disorders such as Graves' disease, chronic thyroiditis and myxedema, the incidence of thyroid antibodies was studied in relatives of patients with thyroid disorders. The relatives studied were all limited within a two degree relationship of the patients. Serum antibodies to thyroglobulin and thyroid microsome were determined by susing the method of a hemagglutination test. The following results were obtained; 1) Thirty six of 103 relatives (35%) were found to have such antibodies, and sixteen (7.0%) of 230 hospital controls were positive. This difference was significant (P less than 0.001). 2) There was no difference in the incidence among relatives of patients with Graves' disease and those chronic thyroiditis. 3) With regard to age, the incidence in the more than 20 years old group was significantly greater than that in the under 19 years old group. 4) There was no difference in the incidence between male and female. These results suggested that the relatives of patients with so-called autoimmune thyroid disorders may have a predisposition for thyroid disorders.