问题 问答题 简答题

RAPD标记的原理与常规的PCR技术不同之处主要表现在哪些地方?

答案

参考答案:

RAPD标记的原理同PCR技术主要表现在以下3个方面:

①引物。常规的PCR反应所用的是一对引物,长度通常为20bp(碱基对)左右;RAPD所用的引物为一个,长度仅10bp。

②反应条件。常规的PCR复性温度较高,一般为55—60℃,而RAPD的复性温度仅为36℃左右。

③扩增产物。常规PCR产物为特异扩增,而RAPD产物为随机扩增。这样,RAPD反应在最初反应周期中,由于短的随机单引物,低的退火温度,一方面保证了核苷酸引物与模板的稳定配对,另一方面因引物中碱基的随机排列而又允许适当的错配,从而扩大引物在基因组DNA中配对的随机性,提高了基因组DNA分析的效率。

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