The majority of patients (about 90%) with a clinical diagnosis of OI have a mutation in the COL1A1 or COL1A2 genes, which shows an autosomal dominant pattern of inheritance. Six other genes, CRTAP, LEPRE1, FKBP10, PP1B, SP7/Osterix (OSX), and SERPINH1, are associated with autosomal recessive forms of OI.