Statistical method for mapping QTLs for complex traits based on two backcross populations  

作　　者：ZHU ZhiHong HAYART Yousaf YANG Jian CAO LiYong LOU XiangYang XU HaiMing 

机构地区：[1]Agronomy Department,College of Agriculture and Bioteehnology,Zhejiang University,Hangzhou 310058,China [2]Department of Mathematics,Statistics and Computer Science,NWFP Agricultural University Peshawar,Peshawar 25130,Pakistan [3]China National Rice Research Institute,National Center for Rice Improvement,State Key Laboratory of Rice Biology,Hangzhou 310006,China [4]Department of Biostatistics,School of Public Health,University of Alabama at Birmingham,Birmingham,Alabama 35294,USA

出　　处：《Chinese Science Bulletin》2012年第21期2645-2654,共10页

基　　金：supported by the National Basic Research Program of China(2010CB126006and2011CB109306);the National Special Program for Breeding New Transgenic Variety(2008ZX08005-005);CNTC(110200701023);YNTC(08A05);the National Institutes of Health(R01DA025095)

摘　　要：Most important agronomic and quality traits of crops are quantitative in nature.The genetic variations in such traits are usually controlled by sets of genes called quantitative trait loci (QTLs),and the interactions between QTLs and the environment.It is crucial to understand the genetic architecture of complex traits to design efficient strategies for plant breeding.In the present study,a new experimental design and the corresponding statistical method are presented for QTL mapping.The proposed mapping population is composed of double backcross populations derived from backcrossing both homozygous parents to DH (double haploid) or RI (recombinant inbreeding) lines separately.Such an immortal mapping population allows for across-environment replications,and can be used to estimate dominance effects,epistatic effects,and QTL-environment interactions,remedying the drawbacks of a single backcross population.In this method,the mixed linear model approach is used to estimate the positions of QTLs and their various effects including the QTL additive,dominance,and epistatic effects,and QTL-environment interaction effects (QE).Monte Carlo simulations were conducted to investigate the performance of the proposed method and to assess the accuracy and efficiency of its estimations.The results showed that the proposed method could estimate the positions and the genetic effects of QTLs with high efficiency.Most important agronomic and quality traits of crops are quantitative in nature.The genetic variations in such traits are usually controlled by sets of genes called quantitative trait loci （QTLs）,and the interactions between QTLs and the environment.It is crucial to understand the genetic architecture of complex traits to design efficient strategies for plant breeding.In the present study,a new experimental design and the corresponding statistical method are presented for QTL mapping.The proposed mapping population is composed of double backcross populations derived from backcrossing both homozygous parents to DH （double haploid） or RI （recombinant inbreeding） lines separately.Such an immortal mapping population allows for across-environment replications,and can be used to estimate dominance effects,epistatic effects,and QTL-environment interactions,remedying the drawbacks of a single backcross population.In this method,the mixed linear model approach is used to estimate the positions of QTLs and their various effects including the QTL additive,dominance,and epistatic effects,and QTL-environment interaction effects （QE）.Monte Carlo simulations were conducted to investigate the performance of the proposed method and to assess the accuracy and efficiency of its estimations.The results showed that the proposed method could estimate the positions and the genetic effects of QTLs with high efficiency.

关 键 词：回交群体 品质性状 基因定位 统计方法 数量性状位点 上位性效应 基础 相互作用 

分 类 号：S336[农业科学—作物遗传育种]