Matsui Y, Yasui N, Kawabata H, Ozono K, Nakata K, Mizushima T, Tsumaki N, Kataoka E, Fujita Y, Ochi T
Department of Orthopaedic Surgery, Osaka Medical Center and Research Institute for Maternal and Child Health, Japan.
J Hum Genet. 2000;45(2):105-8. doi: 10.1007/s100380050024.
Metaphyseal chondrodysplasia of the Schmid type (MCDS) is a skeletal dysplasia affecting the long bone metaphyses; it is characterized by short stature, bowlegs, and coxa vara. The spine is generally not involved. Here we report a novel missense mutation of the type X collagen gene in a sporadic case of MCDS. The mutation was a heterozygous single base-pair transition of G-to-A at nucleotide 1783, which predicted a substitution of glycine by arginine at codon 595 (G595R) in the carboxyl-terminal noncollagenous domain. Interestingly, another mutation of the same codon, in which glycine is substituted by glutamic acid (G595E), was previously reported to cause spondylometaphyseal dysplasia (SMD), another group of skeletal dysplasias with involvement of the spine in addition to the long tubular bones. The novel G595R mutation identified in the present study supports the concept of type X collagenopathy.
施密德型干骺端软骨发育不良（MCDS）是一种影响长骨干骺端的骨骼发育异常；其特征为身材矮小、弓形腿和髋内翻。脊柱通常不受累。在此，我们报告了一例散发型MCDS病例中X型胶原蛋白基因的一个新的错义突变。该突变是核苷酸1783处从G到A的杂合单碱基对转换，预测在羧基末端非胶原蛋白结构域的第595密码子处甘氨酸被精氨酸替代（G595R）。有趣的是，先前报道同一密码子的另一个突变，即甘氨酸被谷氨酸替代（G595E），会导致脊椎干骺端发育不良（SMD），这是另一组除长管状骨外还累及脊柱的骨骼发育异常。本研究中鉴定出的新的G595R突变支持了X型胶原蛋白病的概念。
