Objective: A recent report has demonstrated a stronger association between the HLA-DQA1*0501 allele and Graves' disease in Caucasian men than in women. Our aim was to confirm this association in a larger series of male Caucasian patients.
Design: Polymerase chain reaction/sequence specific oligonucleotide probing (PCR/SSOP).
Patients: Fifty men and 70 women with Graves' disease were studied as well as a control group consisting of 57 healthy, unrelated men and women.
Methods: Genomic DNA was derived from venous blood samples. Appropriately primed DNA was amplified by PCR and the products were subjected to SSOP. The presence of the allele was demonstrated by enhanced chemiluminescence.
Results: A significant association between HLA-DQA1*0501 and Graves' disease was demonstrated among both the men and women as well as in the combined disease cohort, with HLA-DQA1*0501 conferring a greater relative risk than HLA-DR3 in all three groups. This association persisted when the results from the DR3-negative Graves' patients were analysed in isolation. HLA-DQA1*0501 was heterogeneously distributed between the sexes with significantly more female Graves' patients carrying this allele.
Conclusions: There is a significant association between HLA-DQA1*0501 and Graves' disease which may be unrelated to the inheritance of this allele on an extended haplotype with HLA-DR3. In contrast to a recent report, HLA-DQA1*0501 was significantly more prevalent among women with Graves' disease than men.