It is characterized by mild bone fragility and slight joint and ligament instability. Individuals with this condition are typically of average stature and display minimal limb deformities. Once growth is complete, the occurrence of fractures decreases substantially, but additional medical problems, such as early onset hearing loss and brittle teeth, may develop. This type of Osteogenesis Imperfecta is dominantly inherited from a parent or acquired as result of a spontaneous mutation. The genetic mutation affects the COL1A1 gene resulting in a decreased quantity of collagen (Fast Facts- Osteogenesis Imperfecta Foundation, …show more content…
A deformity of the hip, called coxa vara, is common within this subtype along with a varying degree of fracture incidences. Individuals with Type VII are typically of short stature and may have shortened humeri and femora. Unlike the previous six types of Osteogenesis Imperfecta, Type VII is recessively inherited and the CRTAP gene is affected. In order to be recessively inherited both parents must be carriers of the gene and the affected individual acquires two copies of the mutated allele. In this case, mutation of the CRTAP gene affects the maturation process of collagen (Fast Facts- Osteogenesis Imperfecta Foundation,