Background rheumatoid arthritis (RA) is a complex polygenic disease. HLA-DRB1 alleles encoding the shared epitope (SE) are associated with RA susceptibility and severity. Recently HLA-DRB1 SE alleles has been reclassified into S1, S2, S3P and S3D groups.
Objectives assessed the impact of this new classification of the HLA-DRB1 SE+ in RA susceptibility and structural severity.
Methods serum and genomic DNA samples of 154 RA patients and 95 healthy controls were obtained. HLA-DRB1 genotyping and sub typing was performed by PCR- sequence specific probes (PCR-SSP). Rheumatoid factor (RF) and C-reactive protein (CRP) were quantified by nephelometry. ACPAs were detected by ELISA. Disease activity was assessed using the DAS28-VS and radiographic damage by Sharp Vander Heidje method
Results we found a positive association between RA susceptibility and S3P alleles (OR=2.94, 95% CI 1.82 to 4.84; p<7.10-5) and S2 alleles (OR=2.71, 95%CI 1.047 to 8.17; p<0.04). In opposite, a negative association was found for S1 alleles (OR =0.58, 95% CI 0.37 to 0.89, p<0.01) and X alleles (OR=0.59, 95% CI 0.40 to 0.86; p<5.10-3). No significant association was observed for the S3D class of alleles (13.9% vs 14.2%, p<0.93). Finally we didn’t observe any association between the HLA-DRB1 alleles and structural severity.
Conclusions According to the revised classification, RA susceptibility alleles in Algerian patients were S2 and S3P groups alleles but the protective alleles were S1 and X alleles. Our results support the hypothesis of a differential role played by different HLA-DRB1 allele groups in RA susceptibility and structural severity.
Disclosure of Interest None Declared
Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.