Extended report: Gene–environment interaction between HLA-DRB1 shared epitope and heavy cigarette smoking in predicting incident rheumatoid arthritis

摘要

Background:Previous studies have reported an interaction between ever cigarette smoking and the presence of the human leukocyte antigen (HLA)-DRB1 shared epitope (SE) genotype and rheumatoid arthritis (RA) risk. To address the effect of dosage, a case-control study nested within two prospective cohorts to determine the interaction between heavy smoking and the HLA-SE was conducted.