Gardiner K, Graw S, Ichikawa H, Ohki M, Joetham A, Gervy P, Chumakov I, Patterson D
Eleanor Roosevelt Institute, Denver, Colorado 80206, USA.
Somat Cell Mol Genet. 1995 Nov;21(6):399-414. doi: 10.1007/BF02310207.
We have undertaken a detailed analysis of several hundred YACs from widely available YAC libraries which map to human chromosome 21 with the goal of improving the physical map of chromosome 21 and determining the feasibility of producing a minimal tiling path of well characterized, stable, non-chimeric YACs spanning the long arm of the chromosome (21q). We report information on over 500 YACs known to contain STS from 21q including information on size, stability, chimerism, marker content, and NotI restriction sites. YACs derive from the CEPH and St. Louis YAC libraries, and STSs include the set of 198 markers originally used do assemble a YAC contig of 21q, as well as additional anonymous probes and gene markers. This information has assisted in refinements of STS order, has defined a region of general instability in 2lq22.3, has identified an increased number of NotI restriction sites, and has defined cryptic gaps, particularly in 2lq2l, for which few or no markers are available. These results have allowed us to develop and assess a minimal tiling path of overlapping YACs consisting of 59 YACs (and two PI clones), largely non chimeric, stable, and of verified STS content. They total 30 mb of non-overlapping DNA, and contain all chromosome 21 specific STSs originally used to define the 810 YAC 21q YAC contig. When integrated with the analysis of a somatic cell hybrid mapping panel of chromosome 21 reported in the accompanying manuscript, a greatly enhanced understanding of the physical map of chromosome 21 is obtained.
我们对来自广泛可用的酵母人工染色体（YAC）文库的数百个YAC进行了详细分析，这些YAC定位于人类21号染色体，目的是改进21号染色体的物理图谱，并确定构建跨越该染色体长臂（21q）的特征明确、稳定、非嵌合YAC的最小拼接路径的可行性。我们报告了500多个已知包含21q上序列标签位点（STS）的YAC的信息，包括大小、稳定性、嵌合性、标记物含量和NotI限制性酶切位点等信息。YAC来自CEPH和圣路易斯YAC文库，STS包括最初用于组装21q的YAC重叠群的198个标记物，以及其他匿名探针和基因标记物。这些信息有助于完善STS顺序，确定了21q22.3区域普遍不稳定，发现了更多的NotI限制性酶切位点，并确定了隐蔽间隙，特别是在21q21区域，该区域几乎没有可用的标记物。这些结果使我们能够开发和评估由59个YAC（和两个PI克隆）组成的重叠YAC的最小拼接路径，这些YAC大多是非嵌合的、稳定的，且STS含量经过验证。它们总共包含30兆碱基对的非重叠DNA，并包含最初用于定义810个21q YAC重叠群的所有21号染色体特异性STS。当与随附论文中报道的21号染色体体细胞杂种定位板分析相结合时，对21号染色体物理图谱的理解得到了极大增强。
