Mutational hot spot in the DSPP gene causing dentinogenesis imperfecta type II
Mutational hot spot in the DSPP gene causing dentinogenesis imperfecta type II
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DOI：
10.1007/s00439-004-1223-6
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发表时间：
2005-02-01
期刊：
影响因子：
5.3
通讯作者：
Simmer, JP
中科院分区：
文献类型：
--
作者：
Kim, JW;Hu, JCC;Simmer, JP
目前牙齿牙本质遗传性缺陷的分类系统基于临床和放射学检查结果，包括两种类型的牙本质发育不良（DD）和三种类型的牙本质发育不全（DGI）。然而，DGI III 型是否应被视为独特的表型或 DGI II 型的变异尚有争议。自首次提出分类系统以来的 30 年来，遗传性牙本质缺陷的遗传病因学取得了重大进展。 II 型 DGI 被认为是一种常染色体显性遗传疾病，具有几乎完全外显率和低频率的新发突变。我们在一个韩国家族（从头开始）和一个白种人家族的 DSPP（牙本质唾液酸磷蛋白）基因的外显子 3 的第一个核苷酸处发现了一个突变（c.52G --> T，p.V18F）。此前曾有报道称，该突变在一个中国家庭中引起了 II 型 DGI。这些发现表明，该突变位点代表了 DSPP 基因中的突变“热点”。这两个家族的临床和放射学特征包括与 DGI II 型和 III 型相关的经典表型。发现单个突变导致两种表型模式强烈支持这样的结论：DGI II 型和 DGI III 型不是单独的疾病，而是单一疾病的表型变异。我们提出了 莫迪。现行分类系统的阳离子，因此“遗传性乳光牙本质”或“DGI II 型”这一名称应用于描述 DGI II 型和 III 型表型。
The current system for the classification of hereditary defects of tooth dentin is based upon clinical and radiographic findings and consists of two types of dentin dysplasia ( DD) and three types of dentinogenesis imperfecta (DGI). However, whether DGI type III should be considered a distinct phenotype or a variation of DGI type II is debatable. In the 30 years since the classification system was first proposed, significant advances have been made regarding the genetic etiologies of inherited dentin defects. DGI type II is recognized as an autosomal dominant disorder with almost complete penetrance and a low frequency of de novo mutations. We have identified a mutation ( c. 52G --> T, p. V18F) at the first nucleotide of exon 3 of the DSPP ( dentin sialophosphoprotein) gene in a Korean family ( de novo) and a Caucasian family. This mutation has previously been reported as causing DGI type II in a Chinese family. These findings suggest that this mutation site represents a mutational "hot spot'' in the DSPP gene. The clinical and radiographic features of these two families include the classic phenotypes associated with both DGI type II and type III. Finding that a single mutation causes both phenotypic patterns strongly supports the conclusion that DGI type II and DGI type III are not separate diseases but rather the phenotypic variation of a single disease. We propose a modi. cation of the current classification system such that the designation "hereditary opalescent dentin'' or "DGI type II'' should be used to describe both the DGI type II and type III phenotypes.