Polymorphisms within the RANK and RANKL Encoding Genes in Patients with Rheumatoid Arthritis: Association with Disease Progression and Effectiveness of the Biological Treatment

This study enrolled 318 RA patients and 163 controls.RANK (rs8086340, C  >  G; rs1805034, C >  T) andRANKL (rs7325635, G  >  A; rs7988338 G >  A) alleles were determined by real-time PCR with melting curve analysis and related with clinical parameters. In addition, RANKL serum levels were measured by ELISA. TheRANK rs8086340-G allele was overrepresented among patients as compared to controls (OD  = 1.777,p = 0.038). C-reactive protein (CRP) levels were significantly (p <  0.05) associated withRANK rs8086340 polymorphism and were higher in theCC-homozygotes at the baseline while lower in theGG-carriers at the 12th week of the treatment. At the latter time pointRANKL rs7325635-GG-positive patients also showed significantly lower CRP concentrations. Higher alkaline phosphatase levels before induction of anti-TNF therapy were observed inRANK rs8086340 andRANK rs1805034CC homozygotes (p = 0.057 andp = 0.035, respectively). TheGG homozygosity of bothRANKL single nucleotide polymorphisms was significantly associated with the number of swollen joints (rs7988338 and rs7325635, before and at the 12th week of therapy, respectively,p <  0.05 in both cases). These results imply that polymorphisms within theRANK andRANKL genes affect RA susceptibility and anti-TNF treatment outcome.
Source: Archivum Immunologiae et Therapiae Experimentalis - Category: Allergy & Immunology Source Type: research