DETECTING AND MAPPING SEQUENCE CHANGES IN DNA

目前研究的目标是生成一张老鼠的地图 一种基因组，其中所有的染色体都用大约间隔开的位置标记 相隔十个地图单元。这些基因座应具有多态特征 变异，使得任何给定的菌株对没有最近的 近亲交配史上大约有一半的基因座上有不同的等位基因。这个 能够满足这些要求的单一类型的遗传标记是 小鼠DNA中的限制性片段长度多态性。我们计划绘制地图 这些变体使用了各种映射技术。重点放在 将使用重组近交系菌株。其他技术将 涉及分离小鼠染色体的体细胞杂交，经典的 回交和同源品系的小鼠。我们计划用来探测DNA 几种克隆的序列。首先，我们将使用已识别的克隆 从其他实验室获得的cDNA探针。这些都有内在的 兴趣以及增加地图。第二，我们将使用我们所使用的探测器 知道与多态基因座很少的染色体杂交。这些 克隆将在与来自一组 小鼠-仓鼠杂交细胞系。它们将分为两种类型。我们将使用 从多个小鼠器官的文库中随机克隆出cdna。我们也 计划使用侧翼区域来内源性逆转录病毒，我们将克隆 用于C57BL小鼠品系的DNA基因组文库。我们已经证明了 这些逆转录病毒在C57BL上占据与逆转录病毒不等位的基因座 其他菌株的基因座。这意味着它们将杂交到 多态DNA片段。该片段将含有C57BL中的逆转录病毒 并将在其他毒株中缺乏逆转录病毒。因为逆转录病毒似乎 随机插入的小鼠基因组和小鼠品系每个大约有130个 拷贝，它们将在小鼠基因组上间隔约12厘米，并将 出现在每一条染色体上。一只完全有标记的小鼠的成就 MAP对于全面解释和分析法规是必不可少的 基因、多基因表型和肿瘤易感性。

The goal of the current study is the generation of a map of the mouse genome in which all chromosomes are marked by loci, spaced approximately ten map units apart. These loci should be characterized by polymorphic variation, such that any given pair of strains which do not have a recent inbreeding history have different alleles at about half the loci. The single type of genetic marker which could fulfill these requirements is the restriction fragment length polymorphism in mouse DNA. We plan to map these variants using a variety of mapping techniques. The main emphasis will be on use of recombinant inbred strains. Other techniques will involve somatic hybrids segregating mouse chromosomes, the classical backcross and congenic strains of mice. We plan to probe the DNA with several kinds of cloned sequences. First, we will use identified cloned cDNA probes obtained from other laboratories. These have intrinsic interest as well as adding to the map. Second, we will use probes which we know hybridize to chromosomes which have very few polymorphic loci. These clones will be identified after hybridizing to DNA from a panel of mouse-hamster hybrid cell lines. They will be of two types. We will use random cDNA clones from libraries from a number of mouse organs. We also plan to use flanking regions to endogenous retroviruses which we will clone for genomic libraries of DNA from C57BL mouse strains. We have shown that these retroviruses occupy loci in C57BL which are not allelic to retroviral loci in other strains. This implies that they will hybridize to polymorphic DNA fragments. The fragment will contain a retrovirus in C57BL and will lack a retrovirus in other strains. As retroviruses appear to insert randomly in the mouse genome and mouse strains each have about 130 copies, they will be spaced about 12 cM apart on the mouse genome, and will be present on every chromosome. The achievement of a fully marked mouse map is essential to the full interpretation and analysis of regulatory genes, multigene phenotypes, and tumor susceptibility.