Group specific component (GC) phenotypes in rheumatoid arthritis: absence of an association

Abstract

Group Specific Component (GC) is a major vitamin D-binding protein in plasma. It mediates bone resorption by activating osteoclasts and also there is decreased expression of GC in Rheumatoid Arthritis (RA) patients. The current study tried to investigate any association between GC phenotypes and progress of RA in South Indian population. This study is conducted on 185 subjects of which 85 are RA patients and 100 age and sex matched controls. GC phenotypes were determined by using 7% polyacrylamide gels. All statistical analyses were done using SYSTAT 12 software and a probability value of <0.05 was considered statistically significant. The frequency of GC-1 allele is higher and GC-2 allele is lower in both patients and controls respectively. In both the subjects the frequency of 1-1 phenotype is high and 2-2 phenotype is low and there is equal distribution of 2-1 phenotype. GC phenotypes are also not associated with clinical parameters [Hb, ESR, TC and DC] and clinical features (Morning stiffness, Rheumatoid factor, Age of onset and Gender). There is no association between GC phenotypes and RA.