Table 2 Comparison of phenotypes observed in zebrafish, mice and human due to loss of function of CCN2 gene.
From: Biallelic variants in CCN2 underlie an autosomal recessive kyphomelic dysplasia
Phenotypes observed due to loss of function of CCN2 | ccn2a knockout zebrafish | Ccn2 deficient mice | Individuals with biallelic CCN2 variants |
|---|---|---|---|
Craniofacial abnormalities | Underdeveloped ceratohyal arches, bent ceratobranchial arches and misshapen Meckel’s cartilage | Shortened mandibles, deformed Meckel’s cartilage and ethmoid bones, domed cranial vault, and secondary cleft palate | Bitemporal narrowing, posteriorly placed ears, deviated nasal septum, short/bifid uvula, crowded teeth, micrognathia, microstomia and retrognathia |
Vertebral/ ribs abnormalities | Altered body curvature | Short and bent sterna and kinked ribs | Platyspondyly, mild scoliosis and irregularities at vertebral ends |
Upper limb deformities | Not determined | Bends in radius, ulna | Radial head dislocation and bent radius and ulna |
Lower limb deformities | Bent or missing tail | Curved tibia and fibula | Kyphomelic femur, bent tibia and fibula, broad great toes, genu valgum and windswept deformity |
Epi-metaphyseal dysplasia | Not determined | Not determined | Irregular epiphyses and irregular and flared metaphyses |
References | Present study | Ivkovic et al., 2003 | Present study |
