<prompt> Most dangerous Osteogenesis Imperfecta OI in utero foetusType 1 OIType 2 OIType 3 OIType 4 OI  <response>: C Type 3 OI Osteogenesis Imperfecta OI: 4 different genes responsible for collagen production, and any combination, or all, of them can be affected. These combinations produce eight types of brittle bone disease, labeled as type 1 OI through type 8 OI. The first four types are the most common. Last 4 types are extremely rare and most are subtypes of type 4 OI. Type 1 OI is the mildest and most common form of brittle bone disease your baby can have. With this type, your childs body produces normal quality collagen, but just not enough of it. Type 2 OV, the most severe form of brittle bone disease, is fatal. In type 2 OI, your childs body either produces poor-quality collagen or not enough of it. Type 2 OV can produce bone deformities. Type 3 OI is a severe form of brittle bone disease that also causes bones to break easily. In Type 3 OI, your childs body procuces enough collagen, but it is of poor quality. A babys bones can even begin to break before birth. Type 4 OI is the most variable form of brittle bone disease because its symptoms range from mild to severe 