中国对虾生长性状相关遗传标记的筛选与克隆

采用随机扩增多态性DNA(RAPD)技术,对中国对虾“黄海1号”快速生长的第6代群体同一养殖池中生长性状发生分离的两个极端群体、海捕的中国对虾对照群体,进行生长相关遗传标记的筛选。采用240个RAPD引物,共产生标记数2156个。筛选出与生长性状相关的遗传标记65个,其中正相关标记55个,负相关标记10个。依据这些标记在群体中出现的频率和变化规律,筛选出9个特异性标记,其中正相关标记7个,负相关标记两个。对这些特异性标记进行序列测定,获得了6个完整的DNA序列(Genebank注册号DQ185932-DQ185937),并将测序结果进行BLAST分析,发现测得DNA的序列与数据库中已注册序列的相似性较低,未能找到同源性较高的功能基因。根据每一序列重新设计引物,已有两个RAPD标记成功转化为稳定的SCAR标记。

Screening and coloning of the genetic markers related to the growth trait in Fenneropenaeus chinensis

Molecular genetic study was conducted by using RAPD techniques, aiming at identifying genes associated with variation in growth. The sixth generation bred stock of Fenneropenaeus chinensis with faster growth traits,named as "Huanghai No.1", was used in the study. The samples comprised 40 shrimps from same culture pond, belonging to two extreme genomic DNA pools, respectively, viz. fast growth and slow growth. Meanwhile, the wild Chinese shrimp collected from sea was used as the control. 240 high polymorphic RAPD primers were used for analyzing genetic differences between the two DNA pools. On the basis of 2156 fragments produced, 65 fragments were found to be related to growth traits, among them 55 markers were in positive correlation and 10 were in negative correlation. In accordance with the arisen frequency and variation regularity of the markers in stock, 9 specific markers were screened, 7 in positive correlation and 2 in negative correlation. By sequence determination on the specific markers, 6 full DNA sequences (Genebank accession number: DQ185932-DQ185937) were obtained. It was found, through BLAST analysis, that the detected DNA sequences were fairly low in comparability with the registered sequences. Besides, genes with high homologous function were not discovered. Then primers were redesigned according to each sequence, and 2 RAPD markers have been translated into stable SCAR markers successfully.