Spondyloepiphyseal dysplasia congenita (SEDC) is a rare genetic disorder characterized by deformities that begin before birth (prenatally), including skeletal and joint malformations involving the spine, hips and knees and abnormalities affecting the eyes.

Such growth deformities lead to children being shorter than normally would be expected based upon their age and gender (short stature or dwarfism). Some individuals may develop hearing and vision problems. Additional findings can occur in some cases. Intelligence is unaffected. SEDC is caused by mutations in the type II collagen (COL2A1) gene. The disorder is inherited in an autosomal dominant manner, but most cases occur due to a new (de novo) mutation with no previous family history.

Spondyloepiphyseal dysplasia is a form of skeletal dysplasia (osteochondrodysplasia), a broad term for a group of disorders characterized by abnormal growth or development of cartilage or bone. SEDC is characterized by distinctive skeletal malformations affecting the long bones of the arms and legs as well as the bones of the spine (vertebrae). Characteristic involvement includes underdevelopment and fragmentation of the bone and cartilage of the epiphyses, which are the rounded ends or "heads" of the long bones, and underdevelopment or malformation of the vertebrae. There are two main forms of spondyloepiphyseal dysplasia, SEDC and spondyloepiphyseal dysplasia tarda (SEDT).

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