微卫星分子标记在濒危动物保护遗传学研究中的应用

The application of microsatellite DNA markers in conservation genetics of endangered animals

微卫星DNA广泛分布于真核生物基因组中 ,具有多态性高、共显性遗传、选择中性、易于操作等特点 ,是一种极具应用价值的分子遗传标记 ,近年来在濒危动物保护遗传学研究中得到越来越多的应用。微卫星DNA高度多态性提供的高分辨率遗传信息 ,使其不仅适合个体水平的亲子鉴定与交配系统研究 ,而且也已成为种群遗传结构与多样性分析的有效分子标记。微卫星分析所需的DNA量极少 ,用非损伤性方法获取的极少量样品或陈旧样品就能用于有效分析 ,方便了濒危动物野外调查工作的开展 ,并且可以利用年代久远的馆藏历史标本揭示种群的重要历史进程。另外 ,某些微卫星DNA大小在近缘物种间可相互区分 ,这使得部分物种的DNA分子鉴别将更为简便。但微卫星分子标记的座位筛选和特异引物开发耗时费力 ,一定程度上限制了其广泛应用。

Microsatellite DNA is widely dispersed in eukaryotic genomes with the characters of high polymorphism, high abundance, codominance, selective neutrality, and easy manipulation. Therefore, it has been increasingly applied to studies of conservation genetics of endangered animals in recent years. The polymorphism of microsatellite DNA is so high that it can provide excellent resolution not only for kinship and mating system studies at the individual level, but also for genetic structure research at the population level. The DNA template needed for microsatellite analysis is very low and has no special demands, so that small samples obtained with noninvasive method and from old specimen can be analyzed effectively. Therefore, the approach not only makes investigation of endangered animals surviving in the wild more convenient and exact, but also can make use of the rare specimens preserved in museums to reveal important evolutionary history for some species. Furthermore, some microsatellite fragments′ sizes can be discriminated among related species, which makes it possible to identify species more conveniently with only fragment analysis. However, application of microsatellite DNA markers also has its own shortcomings, and appropriate molecular makers should be adopted for a given issue according to different research purposes.