OI, Type IIB (medical condition)

A rare, recessively inherited, lethal form of a genetic connective tissue disorder characterized by fragile bones, blue sclerae and facial and tooth abnormalities. Type IIB has a different origin of the genetic mutation but the clinical features are similar. Type IIB involves a defect on the CRTAP gene on chromosome 3p22. The main difference is that type IIA tends to involve a small head and white or light blue eyes. See also Osteogenesis imperfecta, type IIB