标记密度对标记辅助导入效率的影响  

Effect of marker density on the efficiency of marker- assisted introgression

作　　者：白俊艳[1] 杨又兵[1] 黄勇[1] 祁艳霞[1] 李广录[1] 

机构地区：[1]河南科技大学动物科技学院,河南洛阳471003

出　　处：《黑龙江畜牧兽医》2015年第4期84-87,共4页Heilongjiang Animal Science And veterinary Medicine

基　　金：国家自然科学基金项目(31201777)

摘　　要：为了分析不同标记密度对标记辅助导入一个数量性状基因座(QTL)有利等位基因效率的影响,试验采用两阶段选择策略,前景选择是利用与导入QTL紧密连锁的两侧标记进行间接选择,并将标记辅助最佳线性无偏预测(MBLUP)用于背景选择。结果表明:在回交阶段,不同标记间图距对导入QTL有利等位基因的频率和前景性状的遗传进展影响很小;而在横交阶段,缩小标记间图距可以提高导入QTL有利等位基因的频率和前景性状的遗传进展,但当标记间图距由10 cm缩小到2 cm时,导入QTL有利等位基因频率的变化幅度很小。背景QTL有利等位基因的频率和背景性状的遗传进展在不同标记密度之间基本没有差异,说明当标记间图距小于10 cm时标记辅助导入效率比较高,而且将MBLUP应用于背景选择是可行的。To analyze the effects of different marker densities on the efficiency of favorable allele for a quantitative trait locus（ QTL） with marker- assisted introgression,two- stage selection strategy was used in the test. The two flanking markers tightly linked QTL was used and introgressed to make foreground selection,and the marker- assisted best linear unbiased prediction（ MBLUP） was used to make background selection. The result showed that the map distances with different markers had little effects on the favorable allele frequencies of the introgressed QTL and the genetic processes for foreground traits at the backcross stage,while the shortened map distances between the markers could improve the favorable allele frequencies of the introgressed QTL and the genetic processes for foreground traits at the intercross stage. But when the map distances between the markers were shorten from 10 cm to 2 cm,the change range of the favorable allele frequencies of the introgressed QTL was little.There was basically no difference on the favorable allele frequencies of background QTL and genetic processes for background traits between the markers. The results indicate that the efficiency of marker- assisted introgression is relatively high when the map distances between markers are less than 10 cm,it is feasible that the application of MBLUP is used to the background option.

关 键 词：标记辅助导入 前景选择 背景选择 标记辅助最佳线性无偏预测(MBLUP) 标记密度 

分 类 号：S813.2[农业科学—畜牧学]