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What is HLA associated with rhaumatoid ahritis and explain in detail?
HLA-DR4 (DR4) is an HLA-DR serotype that recognizes the DRB1*04 gene products. The DR4 serogroup is large and has a number of moderate frequency alleles spread over large regions of the worldDR4 is associated with extraaicularrheumatoid ahritis, hydralazine-induced female systemic lupus erythematosus, pemphigoid gestationis, pemphigus foliaceus, obstructive hyperophic cardiomyopathy, IgA nephropathy, 'shared syndrome'-systemic sclerosis/rheumatoid ahritis and polymyalgia rheumatica