CHROMOSOME STRUCTURE

拟议的研究旨在理解原理 染色体结构。 最初将提出三个具体问题 问： (i) 需要哪些遗传决定或信息 果蝇多线染色体的形成？ (ii) 果蝇染色体 11A 区域的序列是什么 负责“嵌间异染色质”的特性和 减数分裂重组？ (iii) 人类染色体中存在脆性 X 突变吗？ 随后的染色体“印记”，导致 DNA 的晚期复制 Xq27？ 本项目的健康相关性如下：问题(i) 可能会导致在培养的人类细胞中诱导多线性的方法， 这将为人类基因图谱绘制提供有用的材料； 问题（2）可以提供对减数分裂特性的见解 适用于人类脆弱X的果蝇染色体 染色体；问题(iii)预计将直接提供 有关人类脆性 X 突变的信息和 假定的染色体印记事件负责 人类遗传性智力低下的最常见原因。 方法涉及细胞遗传学、遗传和分子分析 染色体和DNA。 重组DNA技术、DNA 测序、果蝇 P 元件转化和遗传 分析将用于本研究。

The proposed research is directed at understanding principles of chromosome structure. Three specific questions will initially be asked: (i) What genetic decisions or information are required for formation of polytene chromosomes of Drosophila? (ii) What sequences at Drosophila chromosome region 11A are responsible for the properties of "intercalary heterochromatin" and meiotic recombination? (iii) Does the fragile-X mutation in human chromosomes, and a subsequent chromosome "imprint," lead to late-replicating DNA at Xq27? The health relatedness of this project is as follows: question (i) may lead to methods to induce polyteny in cultured human cells, which would provide useful material for human gene mapping; question (2) may provide insight in meiotic properties of Drosophila chromosomes that are applicable to the human fragile X chromosome; question (iii) is expected to provide direct information about the human fragile X mutation and putative chromosome imprinting event that are responsible for the most common cause of inherited mental retardation in humans. Methodologies involve cytogenetic, genetic, and molecular analysis of chromosomes and DNA. Recombinant DNA technology, DNA sequencing, P-element transformation of Drosophila, and genetic analysis will be used for this research.