GENETIC MAPPING OF MOUSE CHROMOSOMAL GENES

我们一直在进行一项开发多基因座的努力 老鼠的基因图谱。这项工作的大部分是由 种间遗传杂交后代的分析 回交和亚种间回交。这些小鼠的DNA有 已经为各种参考基因座进行了分型，以允许绘制新的 已定义的未知基因定位于基因上的特定位置 连锁图。这些研究导致了一个基因图谱的绘制 大量的基因，包括最近的各种基因 在神经组织、转录调节因子、蛋白质中表达 参与骨形成的激酶和因子。特定地图 位置可能是有用的信息，因为靠近已知的 发育突变可以将这样的基因识别为潜在的 异常表型的候选基因。因此，一个编码主要基因的基因 软骨的结构成分被标示在软骨(Cmd)附近 基质缺乏症)突变，cmd小鼠被证明有7bp 这个基因的缺失。在另一个例子中，小鼠的Merosin基因 被绘制到Dy(肌营养不良症)附近，我们发现了一个 突变小鼠的Merosin缺乏表明这一缺陷 层粘连蛋白基因是导致这种疾病的原因。最后，小鼠 白细胞介素2受体链基因(IL2RG)被定位于 X染色体上XID免疫缺陷突变附近的位置， 尽管进一步的调查表明IL2RG不是 负责XID。

We have been involved in an ongoing effort to develop a multilocus genetic map of the mouse. Most of this work has been accomplished by the analysis of the progeny of two genetic crosses, an interspecies backcross and an intersubspecies backcross. DNAs from these mice have been typed for a variety of reference loci to permit mapping of newly defined genes of unknown map location to specific positions on the linkage map. These studies have resulted in the genetic mapping of a large number of genes including, most recently, various genes expressed in nervous tissue, transcriptional regulators, protein kinases and factors involved in bone formation. Specific map locations can be useful information since proximity to a known developmental mutation can identify such a gene as a potential candidate for the abnormal phenotype. Thus, one gene encoding a major stuctural component of cartilage was mapped near the cmd (cartilage matrix deficiency) mutation, and cmd mice were shown to have a 7 bp deletion of this gene. In another example, the murine merosin gene was mapped near dy (dystrophia muscularis) and we identified a deficiency of merosin in mutant mice suggesting that a defect in this laminin gene is responsible for this disorder. Finally, the murine interleukin 2 gamma receptor chain gene (Il2rg) was mapped to a position on the X chromosome near the xid immunodeficiency mutation, although further investigation indicated that Il2rg was not responsible for xid.