Collagen Type I Alpha 1 Mutation Causes Osteogenesis Imperfecta from Mild to Perinatal Death in a Chinese Family

IntRoductIon Osteogenesis imperfecta (OI), also known as brittle bone disease or Lobstein syndrome, is characterized by blue or gray sclerae, variable short stature, dentinogenesis imperfecta, hearing loss, and recurrent fractures. Based on clinical, genetic, and radiological features, Sillence et al.[1] classified the OI into four subtypes including type I: Mild, common, with blue sclera; type II: Perinatal lethal form; type III: Severe and age‐related progressive deformity, with normal sclera; and type IV: Moderate severity with normal sclera. Based on mutated genes and inheritance patterns, the four subtypes are further classified into 15 types of OI in Online Mendelian Inheritance in Man. More than 90% of the patients with OI have mutations in collagen type I alpha (COL1A) 1 and COL1A2.[2]