OMIM ID:
Spondyloepiphyseal Dysplasia Congenita
Alternate Names
Defective Genes
Clinical Characteristics
Ocular Features
Patients characteristically have vitreous abnormalities described as veils or stands. The central vitreous may undergo liquefaction and the peripheral vitreous sometimes creates traction on the retina. High myopia with progression is common and a significant proportion of patients suffer detachments of the retina even in the absence of myopia. Lattice degeneration is frequently seen. Most patients have 20/50 or better vision.
Systemic Features
Dwarfism with kyphosis and a barrel chest are characteristic. The vertebrae are often flattened and malformed and the neck is short. Delayed ossification in the epiphyses and the os pubis is common. The disorder can be evident at birth but the full syndrome may not be evident until 3 or 4 years of age. Radiologic studies are important in making the diagnosis.
Genetics
Inheritance
This is generally considered an autosomal dominant disorder secondary to mutations in the COL2A1 gene impacting type II collagen. This type of collagen is found primarily in cartilage and vitreous and a number of type II collagenopathy disorders are associated with vitreoretinopathy and joint disease of which Stickler syndrome type I (609508, 108300) is the most common. Other disorders in this database caused by mutations in COL2A1 are: Kniest dysplasia (156550), Stickler syndromes type I (609508, 108300 ) and II (604841), vitreoretinopathy with epiphyseal dysplasia (120140), and spondyloepiphyseal dysplasia congenita (183900).
Pedigree
Autosomal dominant
Autosomal dominant disorders require only one mutation for the disease to be expressed. Since an affected parent has two chromosomes, only one of which has the mutant gene, parents can expect that half (50%) of their children will receive that one and inherit the disease. It is common for individuals that inherit the mutation, however, to not have evidence of the disease (nonpenetrance).
Autosomal dominant inheritance leads to a vertical pattern of transmission