The Cytotoxic T lymphocyte antigen (CTLA-4) is one of the major susceptibility genes associated with autoimmune diseases. Susceptibility to rheumatoid arthritis (RA) is determined by both environmental and genetic factors. The genetic contribution approaches 50-60%. The association between RA with the +49A>G CTLA-4 polymorphism in the Mexican population was investigated.
The polymerase chain reaction-restriction fragment was used to amplify the +49A>G CTLA-4 polymorphism in RA patients and healthy subjects (HS).
We analyzed the association between the +49A>G CTLA-4 polymorphism and RA. The G allele frequency was higher in RA patients than HS (46.8 vs 37.7%, OR=1.45, p=0.01). RA patients carrying the A/G genotype were significantly more likely to be positive to CRP and RF. There was no evidence of an association between SNP genotypes and the clinical characteristics of rheumatoid arthritis.
The +49A>G CTLA-4 polymorphism is a genetic marker of susceptibility for RA in western Mexican population.