COULD HLA-DRB1 BE THE PROTECTIVE LOCUS IN RHEUMATOID-ARTHRITIS

Extensive studies in different ethnic groups have associated the susceptibility to development of rheumatoid arthritis (RA) with the third hypervariable region of the major histocompatibility complex (MHC) HLA-DR beta 1 molecule. On the basis of recent findings in the experimental mouse model of collagen-induced arthritis, Eric Zanelli, Miguel Gonzalez-Gay and Chella David propose that the HLA-DR beta 1 locus is associated with protection to RA and that the actual arthritogenic peptide-presenting molecule is HLA-DQ. Thus, the development of RA would depend upon the expression of the susceptible DQ allele and the nonprotective DRB1 alleles, along with environmental factors that trigger the autoimmune process.