用配子频率法构建多位点分子标记精密连锁图谱

阐述了配子频率法构建多位点分子标记连锁图谱的原理,推导了构建多位点分子标记连锁图谱的数学公式,并以老鼠F2 群体的RFLP数据为例,对其中前 4个连锁位点T175、C35、T93和C66采用配子频率法进行作图分析,与三点自交法和MAPMARKER程序所得结果进行了比较,同时对连锁图距的计算,无效组合的检出进行了分析。     

四倍体彩色马铃薯分子遗传连锁图谱构建研究

以四倍体彩色马铃薯(‘黑美人’,‘MIN-021’)杂交F1代单株无性株系群体为材料,利用SSR分子标记技术及作图软件(TetraploidMap)进行了彩色马铃薯分子遗传连锁图谱的构建研究.结果表明:从255对SSR引物中筛选出34对条带清晰稳定、多态性丰富的适宜引物,对‘黑美人’בMIN-021’杂种F_1的210个单株无性系及其双亲的基因组DNA进行PCR扩增共得到201个多态性标记.用这201个SSR标记对双亲分别作图,首次构建了四倍体彩色马铃薯的分子遗传连锁框架图谱.母本图谱含129个标记,12个连锁群总长度为1 167cM,标记间平均距离为9.04cM;父本图谱含131个标记,12个连锁群总长度为1 187cM,标记间平均距离为9.06cM.     

分子标记技术及其在果树种质资源研究中的应用

分子标记是一种新型的遗传标记，它具有独特的优越性，被广泛地应用于生物学研究的各个领域，本文就当前分子标记的主要类型、特点及在果树品种鉴定、遗传多样性、系谱分析、连锁图谱的构建和基因标记等种质资源研究中的应用及其研究进展进行了简要阐述。     

SSR分子标记的研究进展

介绍SSR分子标记的开发方法,综述了SSR标记在通用性、遗传多样性与种质鉴定、遗传连锁图谱构建、基因定位与克隆、数量性状基因位点(QTLs)分析、DNA指纹图谱构建等研究中的应用及最新进展,对提高SSR分子标记电泳检测效率提出一些建议.同时展望了SSR分子标记的应用前景.     

苦荞重组自交系群体F_5代SSR遗传图谱的构建

以"小米荞×晋荞2号"杂交组合,通过单粒传获得的245个F_5代重组自交系(命名为SJ-RILs)群体为作图材料,构建SSR遗传连锁图谱。结果显示:350对SSR引物在亲本间有多态性的为59对,多态率为16.9%;多态性引物在SJ-RILs群体共扩增出80个等位变异位点;来自小米荞和晋荞2号等位基因分别占群体总基因型的51.5%和48.5%;采用作图Jionmap4.0软件构建的遗传连锁图总长度为1 106.74cm,含11个连锁群,80个分子标记,其中偏分离标记27个,相邻标记的平均间距为13.83cm。结论:该图谱可为苦荞遗传图谱构建、重要性状QTL的定位和基因组学研究隆奠定基础。     

分子标记技术在西瓜遗传育种上的应用研究进展

综述了目前分子标记的主要类型及在西瓜亲缘关系和遗传多样性分析、图谱构建、重要性状基因的连锁标记和杂种纯度鉴定等方面上的应用情况,提出了在西瓜上分子标记的研究趋势.     

分子标记技术及其在果树种质资源研究中的应用

分子标记是一种新型的遗传标记,它具有独特的优越性,被广泛地应用于生物学研究的各个领域.本文就当前分子标记的主要类型、特点及在果树品种鉴定、遗传多样性、系谱分析、连锁图谱的构建和基因标记等种质资源研究中的应用及其研究进展进行了简要阐述.     

应用RAPD标记构建马尾松单株树遗传连锁图谱

利用马尾松（Ｐｉｎｕｓｍａｓｓｏｎｉａｎａ）崇义群体Ｃ－１６号单株上４０粒种子的胚乳为作图群体材料，用随机扩增多态性ＤＮＡ（ＲＡＰＤ）方法构建马尾松单株遗传连锁图谱，从被步筛选的８０个引物中，得到１６个具有多态性产物的引物，对这１６种引物进行Ｍｅｎｄｅｌｉａｎ１：１分离检测（卡方检验，Ｐ＜０．０５），我们得到符合Ｍｅｎｄｅｌｉａｎ１：１分离比例的ＲＡＰＤｓ标记４９个．通过对４９个标记的连锁关系进行分析，其中２９个标记分布在１２个连锁群上，总图距为４８３．３ｃＭ，平均图距为２８．４２ｃＭ，２０个标记没有连锁到任何连锁群上，需要继续进行大量标记的连续分析，构建完善的高密度的遗传图谱，使之能够对数量性状位点ＱＴＬｓ进行定位，从而进行分子标记辅助选择育种（ＭＡＳ）．     

SSR分子标记的开发策略概述

SSR分子标记是一种基于DNA重复序列长度多态性的分子标记技术,是进行群体遗传学结构分析、构建遗传连锁图谱非常有力的工具,应用该技术的前提条件是要有相应的SSR引物.综述了几种有代表性的SSR引物开发策略,旨在为各物种SSR标记的开发提供参考.     

杉木杂种群体分子框架遗传连锁图初报

利用随机扩增ＤＮＡ多态性分子遗传标记－ＲＡＰＤ,以杉木Ｊ０和Ｆ１１两个亲本杂交形成的Ｆ１群体为作图群体,从１０４０个随机引物中筛选出７８个引物,对７８个Ｆ１群体及双亲样本进行了ＲＡＰＤ扩增,共获得１２９个ＲＡＰＤ标记,首次构建了杉木分子遗传连锁框架图,其中Ｊ０亲本包含８个连锁群,标记覆盖的基因组总长度约为５９５．２ｃＭ,Ｆ１１亲本包含４个连锁群,标记覆盖的基因组总长度约为３１５．３ｃＭ。１２９个ＲＡＰＤ标记中偏分离标记占１４．７％。本图谱为构建饱和的杉木分子遗传图谱提供了框架结构,为进一步开展杉木分子遗传方面的研究奠定了基础。     

遗传作图软件应用及辅助软件的研制

介绍了当前普遍用于遗传图谱构建和ＱＴＬ定位的软件ＭＡＰＭＡＫＥＲ３．０（ｆｏｒＰＣ）的功能、数据结构和基本操作命令与步骤；指出了该软件存在的问题与不足。介绍了作者开发的用于遗传图谱构建中方便研究者建立符合ＭＡＰＭＡＫＥＲ要求的分析数据文件，以及对标记的分离比进行检验的辅助软件ＭＤＡＣ。提出了进一步开发中文版新一代遗传作图软件、建立基因组图谱数据库和基于因特网（Ｉｎｔｅｒｎｅｔ）的基因组信息检索等设想。     

Optical mapping of a rice BAC clone using restriction endonuclease and imaging with fluorescent microscopy at single molecule level

A method of constructing restriction map by optical mapping and single molecule fluorescent microscopy is described. DNA molecules were aligned and adsorbed on a glass coverslip surface by a modified “molecular combing” technique, and then the surface-immobilized DNAs were cleaved in situ with a restriction endonuclease. Individual DNA molecules digested by the endonuclease EcoRⅠ were observable with fluorescent microscopy. Using optical mapping, a physical map of a rice bacterial artificial chromosome clone was constructed. This method will facilitate genomic mapping and tracing the dynamic process in real time at a single molecule level with fluorescence microscopy.     

Strategy for the mapping of interactive genes using bulked segregant analysis method and Mapmaker/Exp software

A qualitative trait is usually controlled by a single gene, but it may be sometimes controlled by two or even more genes. This phenomenon is called gene interaction. Rapidly searching for linked mo- lecular markers via bulked segregant analysis (BSA) and then constructing regional linkage map with Mapmaker/Exp has become a common approach to mapping single major genes. However, methods and computer programs developed for mapping single major genes cannot be simply applied to interactive genes because the genetic patterns of gene interac- tions are quite different from that of single-gene in- heritance. Up to now, experimental methods for quickly screening molecular markers linked to inter- active genes and statistical methods and corre- sponding computer softwares for simultaneously analyzing the linkage relationships of multiple mo- lecular markers to an interactive gene have not been available. To solve this problem, in this paper, we propose a strategy for mapping interactive genes using BSA and Mapmaker/Exp. We demonstrate that all interactive genes can be mapped by the 'BSA Mapmaker/Exp' strategy using F2 generation (in a few cases, F3 generation is also needed). As BSA and Mapmaker/Exp have been broadly used in gene mapping studies and are well known by many re- searchers, the strategies proposed in this paper will be useful for practical researches.     

The genetic architecture of divergence between threespine stickleback species.

The genetic and molecular basis of morphological evolution is poorly understood, particularly in vertebrates. Genetic studies of the differences between naturally occurring vertebrate species have been limited by the expense and difficulty of raising large numbers of animals and the absence of molecular linkage maps for all but a handful of laboratory and domesticated animals. We have developed a genome-wide linkage map for the three-spined stickleback (Gasterosteus aculeatus), an extensively studied teleost fish that has undergone rapid divergence and speciation since the melting of glaciers 15,000 years ago. Here we use this map to analyse the genetic basis of recently evolved changes in skeletal armour and feeding morphologies seen in the benthic and limnetic stickleback species from Priest Lake, British Columbia. Substantial alterations in spine length, armour plate number, and gill raker number are controlled by genetic factors that map to independent chromosome regions. Further study of these regions will help to define the number and type of genetic changes that underlie morphological diversification during vertebrate evolution.     

Reconstruction of linkage maps in the distorted segregation populations of backcross, doubled haploid and recombinant inbred lines

Non-Mendelian segregation of markers, known as distorted segregation, is a common biological phenomenon. Although segregation distortion affects the estimation of map distances and the results of quantitative trait loci (QTL) mapping, the effects of distorted markers are often ignored in the construction of linkage maps and in QTL mapping. Recently, we have developed a multipoint method via a Hidden Markov chain method to reconstruct linkage maps in an F2 population that corrects for bias of map distances between distorted markers. In this article, the method is extended to cover backcross, doubled haploid and recombinant inbred line (RIL) populations. The results from simulated experiments show that: (1) the degree that two linked segregation distortion loci (SDL) affect the estimation of map distances increases as SDL heritability and interval length between adjacent markers increase, whereas sample size has little effect on the bias; (2) two linked SDL result in the underesti- mation of linkage distances for most cases, overestimation for an additive model with opposite additive effects, and unbiased estimation for an epistatic model with negative additive-by-additive effects; (3) the proposed method can obtain the unbiased estimation of linkage distance. This new method was applied to a rice RIL population with severely distorted segregation to reconstruct the linkage maps, and a bootstrap method was used to obtain 95% confidence intervals of map distances. The results from real data analysis further demonstrate the utility of our method, which provides a foundation for the inheritance analysis of quantitative and viability traits.     

Localization of genes for lateral branch and female sex expression and construction of a molecular linkage map in cucumber (Cucumis sativus L. ) with RAPD markers

A cucumber ( Cucumis sativus L. ) molecular linkage map, including 79 random-amplified polymorphic DNAs (RAPD)and two genes , lb for lateral branch and f for female sex expression, is constructed from a cross between a line, S52, with weak lateral growing ability and staminate from Dabieshan Mountains area in China and another line, S06, with strong lateral growing ability and gynoecious from Europe. The map contains nine linkage groups and spans 1110.0 cM with an average distance of 13.7 cM between loci. The lb locus is located in a longer linkage group LG-2 and flanked by two markers, OP-Q5-1 and OP-M-2-2, at 9.3 cM and 15.9 cM, respectively. In the meantime, the RAPD loci, OP-Q5-2 and BC151, in a short linkage group were found to flank f at 13.7 cM and 13.4 cM,respectively. The construction of RAPD map has paved a way for further study of the genes for lateral branch, female sex expression and other agronomic traits in cucumber.     

Construction of a genetic linkage map for cotton based on SRAP

DNA markers have been widely used in construction of molecular genetic linkage maps in plants. The first genetic linkage map of cotton was constructed by Reinish in 1994 using RFLP (restriction fragment length polymorphism)[1], which included 705 polymorphic loci on 41 linkage groups with a total length of 4675 cM. Afterwards, several genetic linkage maps were constructed[2—7], but no map is comparable to this one in marker density. A high-density genetic linkage map could be applied effec…     

基于改进型不变分布阈值量化方法的直扩码设计及优选

提出一种基于Tent映射的双向耦合映象格子和改进型不变分布阈值量化方法相结合的直扩码设计方法。为实时产生直扩码,提出通过预设最优映射参数和序列选取方式的优选方法。仿真表明,经改进型不变分布阈值量化方法得到的混沌序列在其他性能不降低的情况下,平衡性得到了提高,且映射的利用率也较高,实时优选出的直扩码的各项性能得到了进一步的提高。     

扁桃种质资源研究进展（综述）

综述了扁桃资源的分布状况和在分子水平上对扁桃资源进行研究的成果，包括利用分子标记进行品种的准确鉴定和辅助育种、遗传图谱构建、分离和克隆编码重要性状的基因和自交不亲和性的研究等方面的内容。     

林木多元性状数据QTL区间作图统计分析及其在杨树上的应用

【目的】传统的数量性状基因座(QTL)定位统计分析方法是针对自交系产生实验群体而建立的,不能直接应用到林木这种杂合度较高生长周期较长的异交物种中。针对林木多元性状数据,将传统的QTL区间作图方法应用到林木杂交F₁代作图群体中。【方法】考虑分子标记各种可能的分离比以及连锁相信息,建立林木多元性状数据QTL定位统计分析模型,并用R语言编写了相应的计算软件包mvqtlmap。在美洲黑杨和小叶杨杂交F₁代群体中,对2014年5月29日至9月24日期间调查的6个时间点树高数据进行了QTL定位分析。【结果】有4个QTL定位在母本美洲黑杨的遗传连锁图谱上,有6个QTL分布在父本小叶杨的遗传连锁图谱上,这些QTL分别位于第1、5、7、9、11和19号染色体上,平均解释0.8%～6.7%的表型方差。【结论】研究结果可为在林木上利用多个性状或多个时间点性状数据进行QTL定位提供统计分析方法及计算工具。所建立的程序包可在网站http://www.bioseqdata.com/mvqtlmap/mvqtlmap.htm上自由下载。