INFLUENCE OF THE HLA-DRB1 LOCUS ON SUSCEPTIBILITY AND SEVERITY IN RHEUMATOID-ARTHRITIS INFLUENCE OF THE HLA-DRB1 LOCUS ON SUSCEPTIBILITY AND SEVERITY IN RHEUMATOID-ARTHRITIS

We examined HLA-DR genotype risks in 288 patients with rheumatoid arth ritis who were carefully categorized for disease severity. Five hundre d ethnically-matched bone-marrow donors were controls. A hierarchy of positive allelic associations was noted with DRB10401(p<10(-38)), *04 04,8 (p<10(-43)), 0405 (p<10(-8)), *10 (p<10(-3)) and *0101,2 (p<10(- 2)), while DRB10403 was negatively associated (p=0.02). The DRB1 geno type relative risks (and 95% Cls) for RA were: 0404,5,8/*0404,5,8 = 3 6.2 (15-87), 0401/*0404,5,8=31.3 (18-55), *0401/*0401=18.8 (11-35), * 0101,2/0404,5,8=6.0 (2-14), 0101,2/*0401=6.4 (3-12), *0101,2/*0101,2= 1.3 (0.3-6), 10/*0404,5,8=27.8 (5-148), *10/*0401=20.8 (5-89), *10/*0 101,2=22.3 (5-96), 0404,5,8/DRX=5.0 (3-8), *0401/DRX=4.7 (3-7), *0101 ,2/DRX=2.3 (1.4-4), 10/DRX=3.4 (0.8-14). No significant correlation o f DRB1 genotypes was found with severity of RA as judged by nodules or articular erosions.