从中国对虾ESTs中筛选微卫星标记的研究

利用生物信息学方法在含有10446个中国对虾ESTs的数据库中进行微卫星序列的筛选，共发现微卫星序列229个，占整个ESTs数据库的2．19％，其中含双碱基重复序列146个和3碱基重复序列58个，分别占在ESTs数据库中发现微卫星序列总数的63．76％，和25．33％，大部分发现的微卫星序列均为Perfect形式的重复序列。根据筛选得到的微卫星序列设计并合成引物19对进行多态性检测，在有扩增产物的16对引物中，首次筛选得到8个中国对虾微卫星标记，并对这些微卫星标记进行了等位基因频率、观测杂合度、期望杂合度、PIC值等统计学指标的评价。结果表明，在8个微卫星位点上，等位基因的数目从5到15不等，等位基因长度从：165～305bp，期望杂合度和多态性信息含量分别为0．59到0．89和0．56到0．88，表明这8个中国对虾微卫星标记完全适合于遗传分析。

Isolation of microsatellite markers from Fenneropenaeus chinensis ESTs

By using the on-line bioinformatics software Repeatmasker, the ESTs database of Chinese shrimp was screened. 229 microsatellite sequences were obtained f rom 10446 ESTs sequences, about 2. 19% in the who le database. A total of 146 dinucleotide repeat s and 58 trinucleotide repeats were found in these 229 microsatellite sequences and most of them were perfect repeats, with ( AT) n in dinucleotide repeats and ( TAA) n in trinucleotide repeats being the most common, about 28. 82% and 17. 03% in the total microsatellite sequences respectively. Nineteen primer pairs were designed from microsatellites using computer program Primer Premier ( Version 5 . 00 ) . Among the 16 primers that can be detected PCR products by electrophoresis, eight primers were polymorphic in about 20 Chinese shrimp samples by electrophoresis analysis. In these eight microsatellite loci, the alleles numbers distributed from 5 to 15, and the range of these alleles were between 165 to 305bp, similar to their predicted size. The expected heterozygosity and the PIC values of them distributed from 0. 59 to 0. 89 and 0. 56 to 0. 88, respectively. These values showed that these 8 microsatellite loci were suitable for genet ic analysis.