We observed that the loss of one Prrx1 allele was not associated with any haploinsufficiency (Figure 6—figure supplement 2) and those Prrx1+/- +/- mice were not protected from lung fibrosis at day 14 after intratracheal instillation of bleomycin (Figure 6—figure supplement 2). This evidence concerns the gene PRRX1 and pulmonary fibrosis.