COL1A2 and osteogenesis imperfecta: According to the inheritance pattern of pathogenic gene mutation, OI patients were divided into autosomal dominant (AD) inheritance, including COL1A1, COL1A2, IFITM5 mutation, and the autosomal recessive (AR) inheritance, including mutations of FKBP10, WNT1, TMEM38B, PLOD2, SERPINF1, BMP1, P3H1, SERPINH1, and CRTAP. Since the patients with autosomal recessive inheritance were quite few, we summarize them into one group.