Patients with Graves' disease (n = 105) had an increased frequency of HLA-B8 (40%) and a reduced frequency of HLA-B12 (24.8%) when compared with random controls (n = 117; 24.8% and 40.2% respectively). Comparison of patients with their first degree relatives (n = 118) shows the frequency deviations in these antigens to be characteristic of the families from which patients with Graves' disease are drawn, rather than of the disease itself. The haplotypes, identified in eight-six patients and 113 relatives, indicate that the excess of HLA-B8 in patients and their relatives is primarily due to the halpotype 1-8. The relative risk for an HLA-B8 individual of developing Graves' disease is 2.02, whilst the relative risk for an individual of haplotype 1-8 is 4.23. No significant associations were found between the incidence of any HLA antigen or combination thereof and the presence or absence of thyroglobulin and thyroid microsomal antibodies, or antibodies which interact with the TSH receptor.

Triiodothyronine (T3) suppression and thyrotropin-releasing hormone (TRH) tests were used to study thyroid function in 50 patients with thyroid disease. The results of the thyroid function tests were compared with the levels of serum thyroid-stimulating immunoglobulins (TSI) measured by a radio-receptor assay. In euthyroid and hyperthyroid patients, the presence of TSI corresponded with the absence of TSH control of thyroid function. However, in two hypothyroid patients with serum TSI levels readily detectable in the receptor assay, T3 suppression and TRH tests indicated that thyroid function was under TSH control.