异源四倍体鲫鲤及其原始亲本遗传变异的RAPD分析

在优化RAPD检测条件的基础上，从100个随机引物中筛选出60个扩增较好的引物对异源四倍体鲫鲤及其原始亲本红鲫和湘江野鲤相互间扩增DNA片段的异同性进行比较研究。结果显示，60个引物共产生1554条带，单一引物扩增的DNA片段数在6～20条之间，片段大小在200～3500bp之间。遗传相似率分析表明，异源四倍体鲫鲤与其原始母本红鲫的相似率为69．41％，与其原始父本野鲤的相似率为64．47％，说明异源四倍体鲫鲤接受原始母本红鲫的遗传物质要多一些；而红鲫和野鲤之间的相似率为42．18％，说明两者的基因组成有较大的相似性，从分子水平证实了红鲫和野鲤的远缘杂交具有较大的亲和性。在分析中，还发现异源四倍体鲫鲤有4条非亲本带，非亲本带谱率达0．72％，这些非亲本带可以作为异源四倍体鲫鲤特异性的分子标记。

RAPD analysis of genetic variation between the allotetraploid hybrid of red crucian carp ? common carp and their original parents

In this study, the random amplified polymorphic DNA( RAPD) technique was used to analyze the genetic variation among the allotetraploid hybrid of red crucian carp ( Carassius auratus red var. , .. ) .. common carp( Cyprinus carpio L. .. ) , red crucian carp and common carp. One hundred 10..nucleotide..long random primers were used in the RAPD analysis. Of these primers, 60 primers produced well..amplif ied and reproducible band patterns. There were 6 to 20 bands ranging in size from about 200 to 3 500 bp in the amplified products of a single primer. After excluding bands that were not clearly identifiable, a total of 1 554 distinguishable fragments were compiled for phylogenetic relationship analysis. The genetic similarity index of the amplif ied DNA bands between the allotetraploid hybrid and their original maternal red crucian carp was 69. 41 % , and the genet ic similarity index of the amplified DNA bands between allotetraploid hybrid and their original paternal common carp was 64. 47 % . The similarity index of the amplif ied DNA bands between red crucian carp and common carp was 42. 18 % . Moreover , 4 specif ic bands were found only in the allotetraploid hybrid, the non..parentage bands ratio of the allotetraploid hybrid was 0. 72 % . The results not only provided the specific molecular markers of the allotetraploid hybrid , but also demonstrated that the allotetraploid hybrid inherited a little more genetic materials f rom their original maternal red crucian carp than their original paternal common carp.