The most robust pairs of genes and miRNAs, collagen, type III, alpha 1 (COL3A1) and Rho guanine nucleotide exchange factor 7 (ARHGEF7), and miR-99b and miR-21*, could perfectly discriminate the ILD samples from controls in this set (see Additional file 5). Here, ARHGEF7 is linked to interstitial lung disease.