Herrinton et al., in their 2013 evaluation of methotrexate and anti-TNFα agents, reported an age/sex-standardized ILD incidence rate, per 1000 PY, of 2.1 (95 % CI 0.0–4.3), with incident ILD observed in 0.8 % of patients with RA treated with an anti-TNF agent and 0.7 % in the methotrexate step-up cohort [19]. This evidence concerns the gene TNF and rheumatoid arthritis.