一种新的DNA分子标记技术——起始密码子-微卫星扩增多态性

综合SCoT和ISSR分子标记技术开发了一种既能将标记位点与表达序列紧密联系，又具有相对较高的多态性的新的分子标记技术——起始密码子一微卫星扩增多态性（start codon-simple sequence repeat, SC-SSR）。SC—SSR标记是基于PCR的目的基因标记系统．上游引物用SCoT标记引物，瞄准基因区域，下游引物用ISSR标记引物，上下游引物间可自由组配。引物设计原则同SCoT标记和ISSR标记。使用50℃的退火温度，保证了扩增结果的稳定性。PCR结果采用琼脂糖凝胶电冰和聚丙烯酰胺凝胶电泳检测。SC—SSR分子标记结合了ISSR标记和SCoT标记的优点，具有操作简单、成本低廉、多态性丰富、重复性好、引物设计简单且通用性良好、同时与表达序列紧密连锁等诸多优点，可用于种质资源的鉴定评价、遗传图谱的构建、重要性状基因标记、gDNA与cDNA指纹分析乃至图位克隆等方面。

A New Molecular Marker Technology Start Codon-Simple Sequence Repeat （SC-SSR）

A new molecular marker technology, start codon-simple sequence repeat （SC-SSR）, was developed based on SCoT and ISSR markers. It is highly polymorphic and associated with expressed sequences. SC-SSR marker is a PCR-based molecular marker system which employed SCoT and ISSR primers as forward and reverse primers, the forward primer aimed to the gene region. The forward and reverse primers could be freely combined. Annealing temperature was set at 50 ℃ in order to guarantee the stability of the amplification results. PCR results were determined by standard agarose gel electrophoresis and PAGE gel. The SC-SSR marker would be adapted for a variety of purposes in different crops including genetic fingerprinting, genetic map construction gene tagging, and genetic diversity studies which combines the advantages of SCoT and ISSR markers, high degree of polymorphism, associated with gene regions, simplicity, reliability, low-cost, excellent repeatability and universal applicability.