ABSTRACT
A 6-month-oldgirl was admitted in Affiliated Children′s Hospital of Capital Institute of Pediatrics with the complaint of “Recurrent fractures within 3 months”. She presented with frequent fractures, skeletal deformities,and distinctive facial features, including wide forehead, ocular proptosis and a flat nose bridge. She was diagnosed as osteoporosis imperfecta based on the clinical characteristics and given pamidronate disodium treatment. The whole exon sequencing showed heterozygous mutation of P4HB gene c.1178A>G (p.Y393C), which leads to a rare type of osteoporosis imperfect a Cole-Carpenter syndrome-1. Eight cases of osteoporosis imperfecta affected by P4HB mutation involving 5 mutationsites were retrieved from literature review. Different mutation sites lead to different clinical manifestations and severity of disease. The genotype-phenotype correlation of osteoporosis imperfect may be associated with the domains of coding proteins.