Aldred M J, Crawford P J, Roberts E, Thomas N S
Institute of Medical Genetics, University of Wales College of Medicine, Heath Park, Cardiff, UK.
Hum Genet. 1992 Dec;90(4):413-6. doi: 10.1007/BF00220469.
A family with X-linked amelogenesis imperfecta (XAI) is described in which the disease is associated with a nonsense mutation in exon 5 of the amelogenin gene. This mutation involves a single base deletion (CCCC-->CCC) in the exon in an affected male, his sister and his mother. The effect of this deletion is to alter the reading frame and to introduce an inappropriate TGA stop codon (an opal mutation) into the exonic sequence of the amelogenin gene immediately 3' of the mutation. The clinical features in the examined members of this family indicate that, in some individuals, the most noticeable defect is of enamel hypoplasia. In others, the hypoplastic changes are subtle and might have been overlooked on cursory examination; the most noticeable change is of enamel colour, indicating a degree of hypomineralisation. We propose that the amelogenin gene is implicated in both the formation of enamel of normal thickness and in the normal mineralisation process.
本文描述了一个患有X连锁型釉质发育不全（XAI）的家族，该疾病与釉原蛋白基因第5外显子的一个无义突变相关。此突变涉及受影响男性、其姐姐和母亲该外显子中的单个碱基缺失（CCCC→CCC）。这种缺失的作用是改变阅读框，并在突变位点下游紧邻的釉原蛋白基因外显子序列中引入一个不适当的TGA终止密码子（乳白突变）。该家族受检成员的临床特征表明，在一些个体中，最明显的缺陷是釉质发育不全。在另一些个体中，发育不全的变化很细微，在粗略检查时可能被忽视；最明显的变化是釉质颜色，表明存在一定程度的矿化不足。我们认为，釉原蛋白基因与正常厚度釉质的形成以及正常矿化过程均有关联。
