HLA-DPB1 POLYMORPHISMS IN PATIENTS WITH HYPERTHYROID GRAVES-DISEASE AND EARLY-ONSET MYASTHENIA-GRAVIS

Using the technique of in vitro enzymatic DNA amplification and dot bl ot hybridization with sequence-specific oligonucleotide (SSO) probes, a study of genetic polymorphism of HLA-DPB1 was performed in 83 unrela ted patients with Graves' disease (GD), 48 patients with early onset m yasthenia gravis (EOMG) and 100 normal British caucasoid subjects who were also tissue typed for HLA-A, B and DR antigens. HLA-DPB1()0401 w as the commonest allele in both patient and control groups with gene f requencies of 0.380, 0.333 and 0.445 for GD, EOMG and controls, respec tively. No significant independent association was found with any HLA- DPB1 allele. As expected, HLA-DR17 is significantly associated with Gr aves' disease (p(c) < 8 x 10(-3), RR = 2.9), while both HLA-B8 and DR1 7 are significantly associated with EOMG (p(c) < 2 x 10(-7), RR = 10.3 and p(c) < 0.02, RR = 3.4, respectively) HLA-DR2 is also significant ly increased in EOMG patients who were negative for HLA-DR17 (p(c) < 0 .02, RR = 6.4). In addition, the co-occurrence of HLA-BS with DPB1()0 402 was significantly commoner in patients with GD (p < 0.021, RR = 6. 2) and EOMG (p < 0.0007, RR = 10.8) than in controls, although the HLA -DPB1()0402 by itself showed no significant increase.