Within the non-IPF ILD subgroup, significant differences were observed between the groups, (One-way Anova test: p= 0.04) and in particular RA-ILD and NSIP, showed significantly increased COL1A1 mRNA expression relative to healthy individuals following pairwise comparisons (t-test, p=0.035 and p=0.024 respectively) (Figure 1, B). This evidence concerns the gene COL1A1 and rheumatoid arthritis.