Jansen's metaphyseal chondrodysplasia (JMC) is a very rare autosomal dominant skeletal dysplasia characterized by short-limbed short stature (due to severe metaphyseal changes that are often discovered in childhood by imaging), waddling gait, bowed legs, contracture deformities of the joints, short hands with clubbed fingers, clinodactyly, prominent upper face and small mandible, as well as chronic parathyroid hormone-independent hypercalcemia, hypercalciuria, and mild hypophosphatemia. The disease is metaphyseal chondrodysplasia, Jansen type (Monarch Disease Ontology entry MONDO_0007982). Also known as: Jansen Type Metaphyseal Chondrodysplasia, Jansen disease, Jansen metaphyseal chondrodysplasia, Jansen metaphyseal dysostosis, Jansen type metaphyseal chondrodysplasia, Jansen's metaphyseal chondrodysplasia, metaphyseal chondrodysplasia murk Jansen type, metaphyseal chondrodysplasia, murk Jansen type.