COL1A2 (p.Gly322Ser) Mutation Causes Late-Onset Osteogenesis Imperfecta: A Case Report

Osteogenesis imperfecta (OI) is a genetically inherited disorder that mainly affects the bones and causes a generalized decrease in bone mass. OI has a broad clinical spectrum ranging from the most severe form of OI which may cause in-utero death or stillbirth to the milder form. Clinical manifestations normally mitigate with an increase in age. We report a case of a healthy 12-year-old male who presented with a spontaneous fracture of the femur without trauma. The patient has no previous history of fractures, bone deformities or systemic conditions. The initial physical examination was unremarkable except for a bilateral subtle grayish sclera. Calcium, phosphorus, vitamin D, blood urea nitrogen (BUN), creatinine, and parathyroid hormone (PTH) values were within normal range. After genetic testing, the patient was diagnosed with OI due to a pathogenic COL1A2 (c.964G>A [p.Gly322Ser]) mutation. The first manifestation was at 12 years of age with a femur spontaneous fracture, which brings to the fact that the patient has a late onset of OI.