Genetic predisposition to thyroid autoimmune disease: Introduction

The appearance of multiple cases of autoimmune disease in members of the same family has been taken as evidence for a genetic predisposition to autoimmunity. Sometimes related individuals have the same disease; more often they have several different autoimmune diseases. Generally, these families have a heightened incidence of either the systemic autoimmune diseases, such as lupus, erythematosus and rheumatoid arthritis, or the organ-specific autoimmune diseases, such as chronic thyroiditis, Graves' disease, insulin-dependent diabetes mellitus, and related autoimmune endocrinopathies; only a few have both. In this discussion, the authors concentrate on autoimmune thyroid disease, in an effort to delineate how genetics may influence the development of autoimmunity and to speculate about the types of genetic factors that may be involved in disease production. Three models of autoimmune thyroiditis are available for genetic studies. First, human chronic thyroiditis is a classic example of organ-specific autoimmunity. Second, many of the essential features of the disease can be reproduced in experimental animals by immunization with the principal thyroid antigen, thyroglobulin. Third, spontaneous forms of thyroditis occur in certain genetically predisposed animals, such as obese-strain chickens. Buffalo rats, and the Argonne colony of beagle dogs.