When stratifying the data from individuals prior to the onset of symptoms of RA according to having the various ACPA specificities, a gene-environment additive interaction for development of RA was found for seropositivity as well as seronegativity; however, there was at least a doubled OR for ACPA-fine specificity-positive individuals, with the exception of anti-Fibα580-600 and anti-Vim60-75 antibodies (Table 5). The gene discussed is PRTN3; the disease is rheumatoid arthritis.