Genetic factors in Hashimoto's struma.

It has previously been established that there is a significant history of thyroid disorders in families of patients with Hashimoto's struma or chronic thyroiditis. In the present study, 99 relatives of 20 patients with Hashimoto's struma or chronic thyroiditis were studied with regard to the incidence of circulating thyroid autoantibodies; 42 of these 99 relatives were found to have such antibodies. Twenty of the 99 relatives were shown to have thyroid abnormalities (chiefly goitre); of this group of 20, antibodies were found in 12. In the remaining 79 persons (who had no clinical evidence of thyroid disease), 30 were found to have circulating antithyroid antibodies. The incidence of such antibodies among these relatives is very significantly greater than in the general population.From these and other similar studies, there is strong evidence favouring a genetic predisposition for Hashimoto's struma and chronic thyroiditis. The mode of inheritance is not yet established, and the pathogenesis of the disease has not yet been elucidated.