利用SSR标记对家蚕黄血基因的定位及连锁分析

SSR Based Linkage and Mapping Analysis of Yellow Blood (Y) Gene in Silkworm,Bombyx mori

位于家蚕第2染色体的黄血基因(yellow blood,Y)控制类胡萝卜素由中肠进入血淋巴,是形成黄色茧系的基础。利用家蚕雌不发生交换的特点,采用黄茧品系KY和白茧品系C108组配正反交BC_1群体(C108×KY)×C108和C108×(C108×KY),分别记作BC_1F和BC_1M,根据已经构建的家蚕SSR分子连锁图谱,对Y基因进行了定位及连锁分析。筛选出6个与Y基因连锁的SSR标记,这些标记在BC_1F群中的所有黄血个体均表现出与(C108×KY)F_1相同的杂合型带型；而所有白血个体带型与亲本C108一致,为纯合型。利用另一个群体BC_1M构建了关于Y基因的遗传连锁图,遗传距离为18．9cM,Y基因位于15．6cM。

Y （Yellow blood） gene, which locates on the 2^nd chromosome of silkworm （Bombyx moil）, controls the uptake of carrotenoid from mid-gut lumen into hemolymph. Owning to lack of crossing over in females, reciprocal backcrossed F1 （BC1） progeny were used for linkage analysis and mapping of the Y gene based on the SSR linkage maps of silkworm constructed by Miao et al. by using silkworm strains C108 and KY which spin white cocoon and yellow cocoon, respectively. The interest gene has been found to be linked to six SSR markers. All the individuals with yellow hemolymph in the BC1F showed heterozygous profile of （C108 KY） F1, and the pupae with white cocoon in BC1F showed the homozygous profile of the strain C108. Using a reciprocal BC1M cross, we constructed a linkage map of 18.9 cM with Ygene mapped at 15.6 cM.