Detection of Some Genetic Polymorphism and Serological Factors Associated with Rheumatoid Arthritis in Egyptian Patients

Abstract

Background: Rheumatoid arthritis is a chronic inflammatory autoimmune disease thatis characterized by destruction of cartilage and bone. PADI4 gene encoding the peptidyl arginine deiminase 4 citrullinating enzyme that has been found to be over expressed in rheumatoid arthritis patients. Objective: To investigate relation between PADI4 gene polymorphisms and anti–cyclic citrullinated peptide (Anti-CCP) autoantibody levels in sera of Egyptian rheumatoid arthritis patients, and to find its relevance to the disease activity(DAS28 score) and other inflammatory markers as Rheumatoid factor (RF). Methods: PADI4-89 andPADI4 -92 single nucleotide polymorphisms (SNPs) were analyzed in thirty RA patients and twenty healthy controls by polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) method. Serum anti-CCP levels were measured by enzyme-linked immunosorbent assay (ELISA). Results: PADI4-89 genotype A/G was present in RA patients at higher frequency compared to controls (P = 0.024). (G) allele frequency was significantly higher in RA patients than in controls (P= 0.047). Level of Anti – CCP was significantly higher in RA patients serum than in controls (P= 0.000).PADI4-89 A/G + G/G genotype and PADI4-92 C/G+GG genotype were associated with higher DAS28 score, Rheumatoid factor (RF), and anti-cyclic citrullinated protein (Anti – CCP). Significant positive correlation was found between serum level of Anti– CCP and DAS28 score (P= 0.023). Conclusion: The SNPs A/G and G/G of PADI4-89 were associated with RA susceptibility. Relation was found between both PADI4 polymorphism and anti-CCP levels.