林木高质量遗传图谱构建和QTL精确定位统计方法及应用

项目名称： 林木高质量遗传图谱构建和QTL精确定位统计方法及应用

项目编号： No.30872051

项目类型： 面上项目

立项/批准年度： 2009

项目学科： 化学工业

项目作者： 童春发

作者单位： 南京林业大学

项目金额： 30万元

中文摘要： 林木具有复杂的生物学特性，其遗传连锁图谱构建和数量性状基因座（QTL）定位的统计分析方法一直没有得到很好的发展。本研究利用林木F1代群体以及不同种类的分子标记,建立了多位点连锁分析的统计模型，使得1:1、1:2:1、1:1:1:1和3:1等分离比的标记位点能同时进行连锁分析；以多位点连锁分析的似然函数值作为目标函数对连锁群中的分子标记排序，可以获得高质量的林木遗传图谱。基于使用各种分离比的分子标记构建的林木遗传连锁图谱，建立了林木QTL区间作图和功能作图统计分析模型，模型考虑了三种QTL分离类型，并以模型选择指数AIC和BIC推断最大可能的QTL分离类型。使用VC++ 6.0编写了林木遗传连锁图谱构建的作图软件FsLinkagMap 2.0、林木QTL区间作图软件FsQtlMap 1.0以及林木QTL功能作图软件3FunMap 1.0，供林木遗传育种学家自由使用。最后，重新构建了美洲黑杨×27431;美杨的遗传连锁图谱，并对杨树的生根性状进行了QTL分析，发现了3个控制杨树生根性状发育轨迹的QTL。本项目研究成果有助于构建林木高密度遗传连锁图和QTL的精确定位。

中文关键词： 林木；遗传连锁图谱；数量性状基因座；统计模型；杨树

英文摘要： Constructing genetic linkage maps and locating quantitative trait loci (QTL) have not well been developed in forest trees because of their camplicated genetic structures. In this study, we established a hidden Markov model for multilocus linkage analysis by incorprating any types of molecular makers that may segregate in 1:1,1:2:1,1:1:1:1 and 3:1 in an F1 population or full-sib family, which is produced by crossing two heterozygous parents in forest trees. By taking the likelihood of an ordered markers as an object function for ordering a linkage group,the genetic linkage maps can be significantly improved.Based on the genetic linakge maps constructed with various types of markers,we proposed statistical models for inverval and functional QTL mapping in a full-sib family.These QTL mapping models took into account three QTL segregation patterns ( segregating in 1:1, 1:2:1 and 1:1:1:1) and adopted AIC and BIC to select the most likely QTL segregation pattern. We have developed three Windows softwares in VC++ 6.0: FsLinkageMap 2.0 for constructing genetic linkage maps, FsQtlMap 1.0 for QTL inverval mapping and 3FunMap 1.0 for functional QTL mapping in forest trees.With our softwares, we re-constrcued the genetic linakge maps for Populus deltoides and P.euramericana, and detected three QTLs that affect the developmental curves of an adventitious root trait. In summary, the results of this study will be helpful for constructing high-density genetic linkage maps and precisely locating QTLs in forest trees.

英文关键词： Forest trees; Genetic linkage map; Quantitative trait locus; Statistical model; Populus