Sclerosteosis 1 (SOST1) [MIM:269500]: An autosomal recessive sclerosing bone dysplasia characterized by a generalized hyperostosis and sclerosis leading to a markedly thickened skull, with mandible, ribs, clavicles and all long bones also being affected. Due to narrowing of the foramina of the cranial nerves, facial nerve palsy, hearing loss and atrophy of the optic nerves can occur. Sclerosteosis is clinically and radiologically very similar to van Buchem disease, mainly differentiated by hand malformations and a large stature in sclerosteosis patients. {ECO:0000269|PubMed:11179006, ECO:0000269|PubMed:11181578, ECO:0000269|PubMed:20583295}. Note=The disease is caused by mutations affecting the gene represented in this entry.; Van Buchem disease (VBCH) [MIM:239100]: VBCH is an autosomal recessive sclerosing bone dysplasia characterized by endosteal hyperostosis of the mandible, skull, ribs, clavicles, and diaphyses of the long bones. Affected patients present a symmetrically increased thickness of bones, most frequently found as an enlarged jawbone, but also an enlargement of the skull, ribs, diaphysis of long bones, as well as tubular bones of hands and feet. The clinical consequence of increased thickness of the skull include facial nerve palsy causing hearing loss, visual problems, neurological pain, and, very rarely, blindness as a consequence of optic atrophy. Serum alkaline phosphatase levels are elevated. {ECO:0000269|PubMed:11836356}. Note=The disease is caused by mutations affecting the gene represented in this entry. A 52 kb deletion downstream of SOST results in SOST transcription suppression causing van Buchem disease.; Craniodiaphyseal dysplasia autosomal dominant (CDD) [MIM:122860]: A severe bone dysplasia characterized by massive generalized hyperostosis and sclerosis, especially involving the skull and facial bones. The sclerosis is so severe that the resulting facial distortion is referred to as 'leontiasis ossea' (leonine faces) and the bone deposition results in progressive stenosis of craniofacial foramina. Respiratory obstruction due to choanal stenosis compromises the clinical outcomes of affected patients. {ECO:0000269|PubMed:21221996}. Note=The disease is caused by mutations affecting the gene represented in this entry. Heterozygous mutations located in the secretion signal of the SOST gene prevent sclerostin secretion and can be responsible for craniodiaphyseal dysplasia.