Case Report: A Novel Homozygous Variant of the Gene in Rare Osteogenesis Imperfecta Type VI.

Osteogenesis imperfecta (OI) is a group of connective tissue disorders with different types of inheritance. OI is characterized by bone fragility and deformities, frequent fractures, low bone-mineral density, and impaired bone micro-architectonics. We described here a case of a one-year-old Tuvan patient with multiple fractures. The disease manifestation occurred first at 12 weeks of age as a shoulder joint bruise, and during the year, the patient sustained 27 fractures. Genetic testing revealed a novel homozygous mutation, c.259_260insCGGCC (p.T87fs), in the gene. This insertion leads to an open-reading frameshift, and the mutation is not represented in the databases. Mutations in lead to type VI OI, the clinical picture of which is similar to the disease phenotype manifestation of the patient. Thus, the patient's diagnosis was established by finding a novel pathogenic variant in the gene.