A routine assay for the direct analysis of HLA-DR-related shared epitope and B27 alleles in chronic inflammatory arthritis

Knowledge of the genetic background of patients with inflammatory arthritis may be useful for disease management. The main markers are the HLA-DR-asso ciated Shared Epitope (SE) for Rheumatoid Arthritis (RA) and HLA-B27 for an kylosing spondylitis. We have developed a simple molecular biology-based te st to provide this essential information. HLA targets are amplified by poly merase chain reaction (PCR), then simultaneously analyzed using 16 individu al hybridization reactions in two 8-well ELISA strips with colorimetric det ection. Concordance was evaluated using a cohort of RA patients with known genotype. Using this new assay, 100% concordance was observed with conventi onal genotyping in RA patients both for HLA-DR SE and B27 genotypes. Sevent y-three percent of the patients with destructive RA had at least one suscep tible allele within SE, compared to 38% of those patients with Don-destruct ive disease. This new assay, which requires minute amount of blood, could b e used to determine the genetic background of inflammatory arthritis, parti cularly in non-specialized settings and for large-scale clinical trials. (C ) 2001 Elsevier Science BN. All rights reserved.