COL1A2 and osteogenesis imperfecta: Mutation of COL1A2 (fetuses 25 and 26) is thought to be associated with osteogenesis imperfecta, a congenital disease characterized by fragile bones, multiple fractures, blue sclera, dentinogenesis imperfecta, and deafness (Marini et al., 2017; Zhang et al., 2016).