用磁珠富集法从AFLP片段中分离微卫星DNA标记

将花生(Arachis hypogaea L．)基因组DNA经酶切后转变成AFLP DNA片段，然后用生物素标记的简单重复序列(SSR)作探针与其杂交，杂交复合物固定到包被有链亲和素的磁珠上，经过一系列的洗涤过程，含有SSR的AFLP片段被吸附在磁珠表面。这些片段经洗脱下来后，先用对应的AFLP引物扩增，再进行克隆和测序，根据SSR两端的保守序列设计引物，经过多态性分析后，便可得到微卫星DNA标记。整个实验过程操作简单、消耗少，可在一周内完成，可作为从植物中分离SSR的一种简单有效的方法。

Microsatellite Enrichment from AFLP Fragments by Magnetic Beads

A simple and efficient method was presented for isolating microsatellite DNA markers from peanut (Arachis hypogaea L.) genome. The genomic DNA was converted into pre-amplified AFLP fragments and hybridized with biotin-labeled SSR probes. Then the hybrid mixture was used to incubate with magnetic beads coated with streptavidin. After washing to remove the non-SSR fragments, the eluted single-strand DNA, which was cloned and sequenced, was largely enriched for microsatellites. Primers can then be designed according to the sequence flanking the repeat motifs and used for polymorphism analysis. The whole experiment can be completed within one week and can be employed as a reliable option for any molecular laboratory to develop SSR markers.