12-month-old boy is brought to the emergency room for examination of his right arm following a tumble at home. Radiologic examination of the limb reveals a recent fracture of the right ulna and evidence of additional healing fractures. The child is noted to have blue sclerae. This patient most likely carries a mutation in a gene that encodes which of the following proteins?

Osteogenesis imperfecta Affects synthesis of type I collagen. Type Iis characterized by a Normal appearance at bih, Fractures of many bones occur during infancy and at the time the child learns to walk. "Fragile as a China doll." Blue sclerae as a result of the deficiency in collagen fibres Incidence of hearing loss Fibrillin gene mutations (choice B) are found in patients with Marfan syndrome. Keratin gene mutations (choice C) are found in patients with epidermolytic hyperkeratosis.