一个新的微卫星多态标记(D14S1435)的FISH定位  

CHROMOSOME ASSIGNMENT OF A NOVEL MICROSATELLITE POLYMORPHIC MARKER (D14S1435) BY FLUORESCENCE IN SITU HYBRIDIZATION

作　　者：郑其平[1] 余龙[1] 张民[1] 胡培蓉[1] 毛宁辉 许月芳[1] 赵寿元[1] 

机构地区：[1]复旦大学遗传学研究所

出　　处：《中华医学遗传学杂志》1998年第3期161-163,共3页Chinese Journal of Medical Genetics

基　　金：国家杰出青年科学基金;国家自然科学基金

摘　　要：目的将从人染色体１４ｑ２４．３显微切割制备的ＤＮＡ文库中分离得到的一个新的微卫星多态标记（Ｄ１４Ｓ１４３５，ＣＡ重复序列，人群中存在１１种等位形式，ＰＩＣ值为０．８５）进行染色体荧光原位杂交（ＦＩＳＨ）返回定位。方法以此多态标记筛选人Ｌａｍｂｄａ／ＤＡＳＨ基因组文库，得到的阳性重组噬菌体ＤＮＡ，通过ＢａｍＨⅠ完全酶切，低熔点胶电泳回收插入片段，再经Ｓａｕ３ＡⅠ酶切，接头捕获ＰＣＲ（ｌｉｎｋｅｒ－ｃａｔｃｈＰＣＲ）法标记探针进行ＦＩＳＨ。结果将这一新的ＳＴＲ精确地定位于人染色体１４ｑ２４．３，证实了从染色体显微切割探针池分离染色体区带特异性遗传标记的可靠性。结论经染色体显微切割、ＰＣＲ及微克隆方法所得到的遗传标记，通过染色体荧光原位杂交证实其确实来自所切割区域，增加了这一区域可用于连锁分析的遗传标记，为定位在１４ｑ２４．３区带内若干遗传病的基因诊断和基因克隆，提供一个新的有价值的遗传标记。Objective Chromosome assignment of a novel microsatellite marker (D14S1435 containing CA repeats and showing 11 alleles and 0.85 of PIC value in Chinese population) isolated from microdissected human chromosome 14q24.3 DNA library by fluorescence in situ hybridization(FISH). Methods The polymorphic marker was used as probe to screen a human Lambda/DASH genome library, a positive clone was isolated and the recombinant phage DNA was extracted as primary material. The insert was recovered through BamH Ⅰ digestion to complete and low melting point agarose gel electrophoresis, after processed with Sau3A Ⅰ the probe was prepared by linker catch PCR method and the following FISH was conducted to metaphase chromosomes. Results This novel STR was precisely mapped to human chromosome 14q24.3, and this demonstrated the validity of isolating chromosome band specific genetic markers from probe pool made by chromosome microdissection. Conclusion Confirmed by chromosome fluorescence in situ hybridization, the novel STR obtained by chromosome microdissection, PCR and subcloning method was really from the microdissected region. This not only increases the numbers of genetic markers used for linkage analysis in the region, but also provides a novel valuable genetic marker for the gene diagnosis and gene cloning of the possible disease causing genes located in the region of 14q24.3.

关 键 词：染色体 微卫星多态 荧光原位杂交 

分 类 号：Q343.2[生物学—遗传学] R394[医药卫生—医学遗传学]