Camurati-Engelmann disease (CAEND, OMIM 131300) is a rare autosomal dominant, progressive diaphyseal dysplasia, which is characterized by hyperosteosis and sclerosis of the diaphyses of long bones. Estimated number of patients with CAEND in Japan is approximately 50-60 by our epidemiological survey. We have reported that domain-specific mutations in transforming growth factor-β1 gene(TGFB1) cause CAEND. Mutations in latency associated peptide(LAP) domain of TGF-β1 destabilize the complex and may hyperactivate TGF signal pathway. We tried to establish CAEND model mice by gene-targeting, but could not because of spermatogenesis defects in chimera mice. We also failed using CRISPR/Cas9 system. Alternatively, we established CAEND patient-derived iPS cells, and are advancing research with them to develop novel therapeutic agents for CAEND.