A novel frameshift deletion in the COL1A1 gene identified in a Chinese family with osteogenesis imperfecta.

Osteogenesis imperfecta (OI) is a genetically heterogeneous group of disorders, characterized by abnormal bone fragility, blue sclera, deafness, joint laxity, and soft-tissue dysplasia. The purpose of this study was to elucidate the genetic or molecular basis for OI type IA in a Chinese family. We evaluated the members of a family, in which six individuals are affected with increased bone fragility and blue sclera. Results of exome sequencing revealed a novel 1-bp deletion (c.2329delG, p.A777fs) in exon 33 of the COL1A1 gene in two affected individuals, but not in a control family member without OI. The variation co-segregated with the disease in all the OI patients but not in the unaffected family members. The mutation caused a frameshift alteration after codon 777, leading to premature termination of the COL1A1 protein. Thus, our findings identified a novel frameshift deletion c.2329delG (p.A777fs) in the COL1A1 gene, which is associated with OI type IA in a Chinese family.