Spondyloepiphyseal dysplasia congenita with absent femoral head.
Spondyloepiphyseal dysplasia congenita (SEDC), an inherited chondrodysplasia, occurs through a mutation in the COL2A1 gene encoding the type II procollagen alpha1 chain, proalpha1 (II). Recently, the authors studied two Korean patients with SEDC. Both these patients had short stature, os odontoideum with or without atlantoaxial instability, platyspondyly, and epiphyseal dysplasia limited to the femoral heads. The more seriously affected patient had shorter height (125 cm), atlantoaxial instability associated with os odontoideum, flat feet, and cleft palate, absence of the femoral head on radiographic and magnetic resonance imaging (MRI), and dislocated proximal femur. The less seriously affected patient was taller (145 cm) and had no atlantoaxial instability, absence of the femoral head on radiography with visible cartilage anlage on MRI, and subluxated cartilaginous femoral head. A mutation analysis was performed using direct sequencing. Two novel dominant mutations were found in the COL2A1 gene of these two patients: G277V and G238S, respectively. Although glycine was substituted with valine and serine in the proalpha1 (II) of these two patients, their phenotypes were significantly different in physical and radiologic evaluations.
Jung
Sung-Chul
SC
Division of Genetic Disease, Department of Biomedical Science, National Institute of Health, Seoul, Korea.
Mathew
Santosh
S
Li
Qi-Wei
QW
Lee
Yong-Jun
YJ
Lee
Kwang-Soo
KS
Song
Hae-Ryong
HR
D000293:Adolescent; D000328:Adult; D001268:Atlanto-Axial Joint; D024043:Collagen Type II / Q000235:genetics*; D004252:DNA Mutational Analysis; D005270:Femur Head / Q000002:abnormalities*; D006621:Hip Joint / Q000000981:diagnostic imaging; D006801:Humans; D007593:Joint Instability / Q000235:genetics; D008297:Male; D020125:Mutation, Missense; D010009:Osteochondrodysplasias / Q000000981:diagnostic imaging / Q000235:genetics*; D010641:Phenotype; D017421:Sequence Analysis; D014057:Tomography, X-Ray Computed
C499177:COL2A1 protein, human; D024043:Collagen Type II