To investigate whether the therapeutic response of rheumatoid arthritis (RA) patients to D-penicillamine is associated with polymorphisms in genes of the glutathione S-transferase (GST) supergene family.
Disease activity in 81 patients with RA treated with D-penicillamine monotherapy was assessed using the Stoke Index, a validated index of disease activity, prior to treatment and at 6 months. GST typing was performed using a polymerase chain reaction-based approach and a logistic regression model was used to investigate any possible association between the therapeutic response to D-penicillamine and the GST genotype.
A poor therapeutic response was associated with the GSTM1 null genotype [odds ratio (OR) 3.94], and in particular with the GSTM1*0/GSTM3*A haplotype (OR 7.63).
Our results suggest that GST polymorphisms may influence the response to D-penicillamine in RA, and that patients in possession of the GSTM1*0/GSTM3*A haplotype are significantly less likely to show a beneficial response to the drug.