Osteogenesis imperfecta with partial trisomy 15.

Osteogenesis imperfecta (OI) is the most common genetic cause of osteoporosis, which presents as multiple fractures of bone. Mutations in the loci COL1A1 on band 17q21 and COL1A2 on band 7q22 have been reported as the cause in most cases of OI, but partial trisomy 15 has not been reported previously as a possible cause. A 3-month-old child with OI with an unusual association of partial trisomy 15 is reported.