利用SSR分子标记对家蚕一种锈色茧性状的连锁分析

Linkage Analysis on a Rusty Cocoon Trait of Silkworm by SSR Molecular Markers

对西南大学家蚕基因资源库保存的一个锈色茧(rusty cocoon)品系进行遗传分析,并配制回交分离群体,提取个体基因组DNA,利用SSR分子标记对其锈色茧性状基因进行连锁检索。遗传分析表明该锈色茧性状由显性单基因控制,与文献记载锈色茧(Rc)性状的遗传规律一致;但该锈色茧性状基因与第6染色体上已知的S0606等3个SSR标记以及新设计引物筛选到的标记E1177均连锁,而与其余连锁群上的SSR标记均独立,表明该锈色茧性状基因属于家蚕第6染色体,与文献记载锈色茧(Rc)基因属于家蚕第2染色体的结论截然不同。将此锈色茧性状基因暂记为Rc1。研究结果为丰富家蚕锈色茧的遗传信息以及准确定位与克隆鉴定该基因奠定了基础。

In this study,we conducted genetic analysis on a rusty cocoon strain preserved in the silkworm（Bombyx mori） gene bank of Southwest University,prepared backcross segregation populations and extracted individual genomic DNA for linkage analysis on the rusty cocoon trait using SSR molecular markers.Genetic analysis indicated that the rusty cocoon trait is controlled by a single dominant gene,which is consistent with the inheritance of rusty cocoon（Rc） in previous report.However,this rusty cocoon locus is linked to the three known SSR markers including S0606 and the newly designed and screened molecular marker E1177,both of which are located on the 6th chromosome of silkworm.This locus is independent with SSR markers on other linkage groups.Therefore,this rusty cocoon gene is located on the 6th chromosome of silkworm.It is clearly different with the previously reported rusty cocoon gene（Rc） which is located on the 2nd chromosome of silkworm.Hence,this rusty cocoon gene was primarily named as Rc1.These results lay an important foundation for genetic information enrichment of silkworm rusty cocoon mutation and for fine mapping and molecular cloning of the candidate gene.