Beyond brittle bones: Genetic mechanisms underlying osteogenesis imperfecta (Review)

Osteogenesis imperfecta (OI) is a heritable genetic disorder characterized by osteoporosis, severe bone fragility and reduced bone mineral density. It is mostly caused by mutations in genes, such as collagen type I alpha 1 chain (<em>COL1A1</em>) and collagen type I alpha 2 chain (<em>COL1A2</em>), which are responsible for synthesizing type I collagen. Of note, 90% of cases of OI are caused by dominantly inherited genes, such as <em>COL1A1</em> or <em>COL1A2</em>, while only 10% of cases are caused by 23 recessive genes. The present review summarizes the genes associated with different types of OI. The present review also highlights the importance of cyclical bisphosphonate treatment for patients with OI for improving bone mineral mass, mobility score, reducing the fracture rate and decreasing pain episodes. The aim of the present review was to provide insight into management policies for the disease, providing knowledge for clinicians/researchers in classifying the types of OI and to ultimately search for more effective therapeutic strategies. Furthermore, the present review provides information that may prove useful for improving patient management, diagnostic accuracy and treatment plans for patients affected by OI, with the aim of enhancing their prognosis.