GENES INVOLVED IN INNER EAR DEVELOPMENT

遗传性先天性耳聋在二零零零年影响约1人 每年出生的孩子。遗传性耳聋起源的研究， 和潜在的治疗方法，将极大地促进这一发展 人类耳聋的小鼠模型。许多小鼠突变体具有听觉 损伤已经存在，但大多数负责基因是 不易被分子克隆获得的。为了加速 了解听力和耳聋的遗传基础，一项计划 同时识别和突变参与肿瘤发生发展的基因 这里提出了小鼠听觉系统。新型LacZ基因陷阱载体 旨在增加可检测到的基因组整合位点的数量， 并有助于鉴定β-半乳糖苷酶(β-GAL)- 表达细胞将使用分子克隆技术构建。 这些载体将被引入多能小鼠胚胎干细胞 (ES)细胞，并对得到的细胞系进行筛选，两者都在 在体外分化后，产生的β-半乳糖活性 从载体整合到表达的基因。ES细胞克隆显示 一种体外调节的β-半乳糖活性模式将用于 产生嵌合胚胎，并对其进行β-半乳糖活性分析 处于不同的发育阶段。产生β-半乳糖的克隆 在发育中的听觉系统和/或 被认为可以诱导听觉系统的周围组织将被用来 以产生携带基因陷阱插入的小鼠品系。一种基因 分析将用于确定被破坏的基因是否会导致 胚胎和/或成人听觉系统中明显的突变表型。 对听觉系统发育很重要的基因，用这个来鉴定 通过与LacZ的连锁，可以很容易地克隆方法 序列，并将随后通过DNA序列分析进行鉴定。 这项研究产生的DNA探针可能会被用于 在未来的连锁研究中，以确定与人类疾病有关的基因。

Congenital deafness with a genetic origin affects approximately 1 in 2000 children born every year. Studies of the origins of genetic deafness, and potential treatments, would be greatly facilitated by the development of mouse models of human deafness. Many mouse mutants with auditory impairment already exist, but the majority of the responsible genes are not readily accessible to molecular cloning. To accelerate the understanding of the genetic basis of hearing and deafness, a scheme to simultaneously identify and mutate genes involved in the development of the murine auditory system is proposed here. New lacZ gene trap vectors designed to increase the number of detectable genomic integration sites, and facilitate the identification of beta-galactosidase (beta-gal)- expressing cells will be constructed using molecular cloning techniques. These vectors will be introduced into pluripotent murine embryonic stem (ES) cells, and the resulting cell lines will be screened, both before and after in vitro differentiation,f or beta-gal activity that results from vector integration into an expressed gene. ES cell clones that show a regulated pattern of beta-gal activity in vitro will be used to generate chimeric embryos which will be analyzed for beta-gal activity at various developmental stages. Clones that give rise to beta-gal expression in components of the developing auditory system and/or the surrounding tissues thought to induce the auditory system, will be used to generate mouse strains that carry the gene trap insertions. A genetic analysis will be used to determine whether the disrupted genes give rise to overt mutant phenotypes in the embryonic and/or adult auditory system. Genes important for auditory system development, identified using this approach, can be cloned easily by virtue of their linkage to lacZ sequences, and will subsequently be identified by DNA sequence analysis. The DNA probes that result from this research could potentially be used in future linkage studies to identify genes involved in human disorders.