To understand how losartan-mediated reduction of TGF-β activity influenced molecular processes underlying disease progression in RDEB in general, we performed unbiased mass spectrometry-based proteomics analyses of whole skin of wild-type, C7-hypomorphic, and losartan-treated C7-hypomorphic mice. This evidence concerns the gene TGFB1 and recessive dystrophic epidermolysis bullosa.