A new variant of galactose‐1‐phosphate uridyltransferase in man: the Los Angeles variant
A new variant of galactose‐1‐phosphate uridyltransferase in man: the Los Angeles variant
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人类半乳糖-1-磷酸尿苷转移酶的新变体：洛杉矶变体
DOI：
10.1111/j.1469-1809.1973.tb01808.x
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发表时间：
1973
影响因子：
1.9
通讯作者：
G. Donnell
中科院分区：
文献类型：
--
作者：
W. Ng;W. Bergren;G. Donnell
人类红细胞半乳糖1-磷酸尿苷转移酶(E.C.2.7.7.12)的第一个已知变体Duarte变体是由Beutler和他的同事(Beutler，Baluda，Sturjo&Day，1965)描述的。Duarte变异基因与半乳糖血症基因等位基因，并以常染色体隐性遗传方式传递(Beutler，Baluda，Sturjo&Day，1966；Gitzelmann，Poley&Prader，1967；Mellman，Tedesco&Feigl，1968)。该变体的特征是活性降低和不同的凝胶迁移率(Mathai&Beutler，1966)。来自Duarte纯合子的溶血物具有大约一半正常的转移酶活性，来自Duarte-正常杂合子的溶血物有四分之三，来自Duarte半乳糖血症杂合子的溶血物有四分之一。在pH为7.0的磷酸盐缓冲液中进行淀粉凝胶电泳会发现，变异酶以一条迁移率比正常酶大的单一条带的形式移动。在不同的电泳系统中，Duarte变异酶显示为三条等距离的条带，而不是正常个体的单一活性条带(Ng，Bergren，Fields&Donnell，1969)。一些呈现三条带的个体的溶血物被发现具有正常或升高的转移酶活性，而不是Duarte变体的活性降低的特征。这一意想不到的发现表明了一种新的变异。家系研究表明，正常或升高的转移酶活性与三带电泳型相关，这是一种遗传特征。新的变种暂时被命名为“洛杉矶变种”(Ng，1971)。这些个体的白细胞提取物中的同工酶图谱也不同于正常的转移酶基因。
The first known variant of human erythrocyte galactose1 -phosphate uridyltransferase (E.C. 2 .7 .7 .12 ) , the Duarte variant, was described by Beutler and his associates (Beutler, Baluda, Sturgeon & Day, 1965). The Duarte variant gene is allelic with the gene for galactosaemia and is transmitted as an autosomal recessive trait (Beutler, Baluda, Sturgeon & Day, 1966; Gitzelmann, Poley & Prader, 1967; Mellman, Tedesco & Feigl, 1968). The variant is characterized by reduced activity and by a different electrophoretic mobility (Mathai & Beutler, 1966). Haemolysates from Duarte homozygotes have approximately half normal transferase activity, from Duarte-normal heterozygotes three-quarters and from Duartegalactosaemia heterozygotes one-quarter. Upon starch-gel electrophoresis in phosphate buffer at pH 7.0, the variant enzyme moves as a single band of greater mobility than for the normal enzyme. In a different electrophoretic system, the Duarte variant enzyme appears as three equidistant bands, in contrast to the single band of activity found for normal individuals (Ng, Bergren, Fields & Donnell, 1969). The haemolysates from some individuals exhibiting triple bands were found to have either normal or elevated transferase activity rather than the reduced activity characteristic of the Duarte variant. This unexpected finding suggested a new variant. Family studies showed that normal or elevated transferase activity in association with a three-banded electrophoretic pattern was an inherited characteristic. The new variant provisionally has been named the 'Los Angeles variant' (Ng, 1971). The isozyme pattern in leucocyte extracts from these individuals also differs from that of the normal transferase genotype.