COL1A1 and osteogenesis imperfecta: Mutations in the type I collagen coding genes (COL1A1 and COL1A2) affecting collagen quantity or structure count for approximately 85% of osteogenesis imperfecta (OI) cases (Marini et al., 2017; Tournis and Dede, 2018; Peng et al., 2021).