Monarch Disease Ontology id MONDO_0010078 (spondyloperipheral dysplasia) is a condition caused by by truncating mutations in the C-propeptide of COL2A1. Like other type II collagen disorders it is characterized by short stature, platyspondyly and epiphyseal dysplasia. A distinguishing feature is the presence of brachydactyly with a prominent first toe. Also known as: spondyloperipheral dysplasia-short ulna syndrome.