DIFFERENT HLA-DQ ARE POSITIVELY AND NEGATIVELY ASSOCIATED IN SWEDISH PATIENTS WITH MYASTHENIA-GRAVIS

The aim of this study was to determine the association between HLA-DQ and myasthenia gravis (MG) in 79 Swedish patients and 155 unrelated po pulation based controls. HLA genotyping was done using polymerase chai n reaction combined with sequence specific oligonucleotide probes, The DQB allele, DQB10201 was positively associated with MG, 39/79 (49%) patients and 43/152 (28%) controls (OR 2.47, Pc = 0.037). DQB1+0201 wa s observed more frequently in patients with an early onset of disease, below 30 years (Pc = 0.033). A negative association was found for DQA 10103, 7/78 (9%) patients and 38/154 (25%) controls (OR 0.30, Pc = 0. 037). DQA10501-DQB1*0201 and DQA1*0201-DQB1*0201 together was signifi cantly increased in patients when compared to controls (OR 2.68; Pc = 0.019). In conclusion, two different DQ2 haplotypes (DQA10501-DQB1*02 01 and DQA10201-DQB1*0201) were positively and the DQA1*0103 allele w as negatively associated with MG. Susceptibility and resistance to MG in Swedish patients is mediated by HLA-DQ.