HUMAN OCULOCUTANEOUS ALBINISM CAUSED BY SINGLE BASE INSERTION IN THE TYROSINASE GENE
HUMAN OCULOCUTANEOUS ALBINISM CAUSED BY SINGLE BASE INSERTION IN THE TYROSINASE GENE
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DOI：
10.1016/0006-291x(89)91767-1
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发表时间：
1989-11-15
影响因子：
3.1
通讯作者：
SHIBAHARA, S
中科院分区：
文献类型：
--
作者：
TOMITA, Y;TAKEDA, A;SHIBAHARA, S
酪氨酸酶阴性眼皮肤白化病（OCA）是一种先天性代谢缺陷，其特征是眼睛和皮肤完全缺乏黑色素。我们分离并鉴定了一名患有酪氨酸酶阴性 OCA 的受影响儿童 (S.S.) 的酪氨酸酶基因。序列分析揭示了外显子 2 中的单碱基插入，该插入改变了阅读框，并在氨基酸残基 298 之后引入了提前终止信号（TGA 密码子）。突变基因的功能分析表明，这种缺乏一个潜在铜结合区的截短酪氨酸酶是无催化活性的。因此，我们得出结论，患者 S.S. 的白化表型是酪氨酸酶基因无义突变引起的酪氨酸酶失活的结果。
Tyrosinase-negative oculocutaneous albinism (OCA) is an inborn error of metabolism, characterized by a complete lack of melanin pigments in the eyes and skin. We have isolated and characterized the tyrosinase gene of one affected child (S.S.) with tyrosinase-negative OCA. Sequence analysis reveals a single-base insertion in the exon 2 that shifts the reading frame and introduces a premature termination signal (TGA codon) after the amino acid residue 298. Functional analysis of the mutated gene indicates that such a truncated tyrosinase lacking one potential copper-binding region is catalytically inactive. We therefore conclude that the albino phenotype of the patient S.S. is a consequence of the inactive tyrosinase caused by the nonsense mutation in the tyrosinase gene.