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COL2A1 Mutation in Spondylometaphyseal Dysplasia Algerian Type
S Matsubayashi1, M Ikema, Y Ninomiya
1Department of Orthopedic Surgery, Nagasaki Prefectural Center of Medicine and Welfare for Children, Isahaya, Tokyo, Japan.
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.
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