水稻基因组中的微卫星标记及其应用

微卫星又叫简单重复序列，是指以少数几个核苷酸(多数为2～4个)为重复单位组成的串联重复序列，微卫星的两侧为保守的单拷贝序列．不同品种间微卫星基序重复次数的不同而形成了多态性，这种多态性可以通过设计PCR引物扩增检测出来，此即为简单序列长度多态性．微卫星标记具有共显性、高多态性、实验操作简单、快捷和检测结果稳定可靠等优点，是一种理想的分子标记．微卫星标记在水稻基因组中非常丰富，且分布均匀，水稻微卫星标记已发展了2740多个．微卫星标记在水稻分子标记连锁图的构建、基因(QTL)定位、系谱分析和分子标记辅助选择、遗传多样性研究和种质鉴定等许多方面得到了广泛应用．

Microsatellite Markers and Their Applications in the Rice Genome

Microsatellites or simple sequence repeats (SSRs),are simple tandemly repeated DNA sequence motif consisting of repeat units of 2~4 bp in length.Microsatellite loci have shown to be highly polymorphic due to variation in the number of repeat units between different varieties.Simple sequence length polymorphism (SSLP) can be detected with polymerase chain reaction (PCR) by selecting the conserved sequences flanking SSR as primers.SSR markers are ideally genetic markers because of their co-dominance,high levels of allelic diversity,ease of assay and high reliability.Microsatellites are very abundant and are evenly distributed throughout the rice genome.More than 2740 SSR markers have been developed in rice.SSR markers have been extensively applied in the construction of rice molecular linkage map,gene (QTL) mapping for important traits,pedigree analysis, molecular marker-assisted selection,the study of genetic diversity and the usage of germplasm.