Table 1 Overview of OI classification and phenotypes
From: Mesenchymal stem cells in the treatment of osteogenesis imperfecta
Forlino Group | Defect | Sillence Type | Gene Symbol | OMIM # | Mode of Inheritance | Severity | Clinical Characteristics |
|---|---|---|---|---|---|---|---|
Group A | Collagen synthesis, structure, or processing | I | COL1A1 or COL1A2 | 166,200 | AD | Mild or non-deforming | Triangular face, minimal bone deformity, tinted sclera, fractures before puberty, hearing loss possible |
II | COL1A1 or COL1A2 | 166,210 | AD | Perinatal lethal | Numerous fractures, severe deformity, underdeveloped lungs, collagen improperly formed | ||
III | COL1A1 or COL1A2 | 259,420 | AD | Severe | Fractures present at birth, tinted sclera, triangular face and spinal curvature, loose joints, poorly developed muscles, aberrant collagen, hearing loss, and respiratory problems | ||
IV | COL1A1 or COL1A2 | 166,220 | AD | Moderate | Short stature, fractures occur before puberty, brittle teeth and hearing loss possible, sclera normal in color, barrel shaped rib cage, collagen improperly formed | ||
XIII | SP7/Osterix | 614,856 | AR | Mild to severe | Joint hyperextensibility | ||
Group B | Collagen modification | VII | CRTAP | 610,682 | AR | Moderate to severe | Clinically similarly to type IV and II, short stature, short humorous and femur, coxa vara is common |
VIII | LEPRE1 | 610,915 | AR | Moderate to severe | Resembles lethal types II and III in appearance and symptom, normal sclera, deficiency of P3HI, skeletal under mineralization, fractures | ||
IX | PPIB | 259,440 | AR | Moderate to severe | Scoliosis, short lower limbs, blue sclera, bowing of limbs, flattened vertebrae, fractures. Similar to types II or III | ||
XIV | TMEM38B | 615,066 | AR | Moderate to severe | Multiple fractures, osteopenia, normal dentition, normal sclera, normal hearing | ||
Group C | Collagen chaperones | X | SERPINH1 | 613,848 | AR | Severe | Short limbs, bowing at the thigh, blue sclera, fractures, triangular face, dentinogenesis imperfecta, respiratory distress, bone deforming, multiple fractures, osteopenia |
XI | FKBP10 | 610,968 | AR | Moderate to severe | Progressive malformation, bone fractures, joint contractures, and kyphoscoliosis, no dentinogenesis imperfecta | ||
Group D | Mineralization | V | IFITM5 | 610,967 | AD | Moderate | Clinically similarly to type IV, large calluses at sites of fractures, calcification of membrane between radius and ulna |
VI | SERPINF1 | 613,982 | AR | Moderate to severe | Clinically similar to type III or IV, alkaline phosphatase activity is slightly elevated | ||
Group E | Osteoblast differentiation | XII | SP7 | 613,849 | AR | Mild to moderate | Bowing of extremities, delayed teeth eruption, poor bone mineralization, hyperextensible joints, low bone density, recurrent fractures, osteoporosis, normal hearing, normal sclera |
XV | WNT1 | 615,220 | AR/AD | Moderate to severe | Short stature, low bone density, early onset fractures, vertebral compression and long bone fractures, bluish sclerae, no dentinogenesis imperfecta | ||
XVI | CREB3L1 | 616,229 | AR | Mild to severe | Prenatal onset of fractures, blue sclerae, bone demineralization, hyperextensibility, decreased ossification of the skull |