阈性状的标记QTL连锁分析  

Linkage Analysis Between Marker and QTL for Threshold Traits

作　　者：刘凤莲[1] 李仁杰[2] 柳楠[1] 孙金海[1] 

机构地区：[1]青岛农业大学动物科技学院,山东青岛266109 [2]青岛农业大学理学与信息科学学院

出　　处：《青岛农业大学学报（自然科学版）》2009年第2期113-118,146,共7页Journal of Qingdao Agricultural University(Natural Science)

摘　　要：采用最大似然区间定位法对阈性状的标记QTL进行连锁分析，并对影响阈性状QTL检测效率的主要因素（性状遗传力、QTL的方差贡献率、标记间重组率、阈值）进行了模拟研究。实验设计的群体为利用标记位点和QTL位点上都为杂合子的公畜与来自随机平衡群体的母畜群交配产生的半同胞个体组成，模拟产生的资源群体大小为500头。研究结果表明：当性状的遗传力较高，QTL方差贡献较大时，检验统计量LR值较大，检验效果较好；遗传力较低，QTL方差贡献较小时，LR值较小，QTL检测效果较差。另外，标记间重组率和阈值对QTL定位的准确度也有直接的影响，随着标记间重组率的增大，QTL定位的效果越差，当阈值在0．2—5之间时，QTL检测效果最好。The marker QTL of threshold traits was analyzed with the method of maximum likelihood in this paper and the major influencing factors of quantitative trait loci （QTL） detection efficiency （ e. g. heritability, QTL effect, recombination and threshold value） were simulated in our study. The experimental populations were half- sibs offsprings of sire whose marker site and QTL site were heterozygote and dam which were from random equilibri- um population, and the population size was 500. The results showed that with the increase of heritability and QTL effect, test statistics （LR） was superior in terms of parameter estimation, and vice versa. It was a more efficient and accurate model of QTL linkage analysis for threshold traits. In addition, the accuracy of QTL mapping was di- rectly influenced by recombination and threshold value. With the increase of recombination, the accuracy of QTL mapping became more inaccurate correspondingly. The effect of QTL mapping was extremely obvious when the threshold value fluctuated between 0.2 and 5.

关 键 词：阈性状 QTL连锁 MONTE-CARLO方法 侧翼标记 最大似然区间定位法 

分 类 号：S813.1[农业科学—畜牧学]