Nakamura Y, Julier C, Wolff R, Holm T, O'Connell P, Leppert M, White R
Nucleic Acids Res. 1987 Mar 25;15(6):2537-47. doi: 10.1093/nar/15.6.2537.
We have examined the structure and DNA sequence of a human genomic locus that consists of a large hypervariable region made up of repeats of a simple sequence. With several restriction enzymes, the locus shows many restriction fragments that vary quantitatively as well as qualitatively. Other restriction enzymes produce only a single, high-molecular-weight fragment at this locus. Almost all of the fragments are revealed with a simple sequence probe. Southern transfers of the high-molecular-weight restriction fragments produced by the restriction enzymes NotI and SfiI, resolved by pulsed-field gel electrophoresis, gave at most two fragments, demonstrated to be allelic, showing that the majority of the restriction fragments seen in the complex patterns are at a single locus. The estimated size of the region homologous to the probe varied from 250 to 500 kilobases. DNA sequencing indicated that the region consists of tandem repeats of a 40-base-pair sequence. Some homology was detected to the tandem repeating units of the insulin gene and the zetaglobin pseudogene hypervariable regions, and to the "minisatellite" DNA at the myoglobin locus.
我们研究了一个人类基因组位点的结构和DNA序列，该位点由一个由简单序列重复组成的大型高变区构成。使用几种限制性内切酶，该位点显示出许多限制性片段，这些片段在数量和质量上都有所不同。其他限制性内切酶在该位点仅产生一个单一的高分子量片段。几乎所有片段都能用一个简单序列探针检测到。通过脉冲场凝胶电泳分离的由NotI和SfiI限制性内切酶产生的高分子量限制性片段的Southern印迹，最多产生两个片段，证明是等位基因，表明在复杂模式中看到的大多数限制性片段位于单个位点。与探针同源区域的估计大小在250至500千碱基之间。DNA测序表明该区域由一个40碱基对序列的串联重复组成。检测到与胰岛素基因和ζ珠蛋白假基因高变区的串联重复单元以及肌红蛋白位点的“小卫星”DNA有一些同源性。
