COL2A1 Mutation in Spondylometaphyseal Dysplasia Algerian Type

Abstract

Spondylometaphyseal dysplasia Algerian type (SMD-A) is an autosomal dominant disorder that was first reported in an Algerian family by Kozlowski et al. [Pediatr Radiol 1988;18:221-226]. Kozlowski's group reported a sporadic case in a 12-year-old Polish boy. They proposed SMD-A as a distinctive skeletal dysplasia and also suggested that a case of SMD reported by Schmidt et al. [J Pediatr 1963;63:106-112] might have had the same disorder. Afterwards, however, no additional report has emerged to date. In addition, the question whether SMD-A belongs to type II collagenopathy (a group of disorders due to a heterozygous mutation of COL2A1) has been continuously under debate. Here we report a 7-year-old Japanese boy with a heterozygous missense mutation in COL2A1, 2582G>T (Gly861Val), whose phenotype matched that of SMD-A. Our observation supports the hypothesis that SMD-A is a variant of type II collagenopathy.

Keywords: COL2A1; Mutation; Spondylometaphyseal dysplasia Algerian type; Type II collagenopathy.

Fig. 1

Radiographs of the patient at the age of 7 years and 11 months. A Hand A-P. Short tubular bones were minimally affected. B, C Spine A-P and lateral. Moderate platyspondyly, minimal scoliosis and hyperlordosis. D Pelvis A-P. Small pelvis, shortening of the sacroiliac notches, flat and irregular acetabulum and granular texture of the capital femoral epiphysis with coxa vara. E Lower extremities. Severe metaphyseal change and valgus deformity of the knees.

Fig. 2

Radiographs of the patient at the age of 9 years and 10 months. Pelvis A-P. The ossification of the proximal femoral epiphyses progressively improves.