DNA分子标记在实验动物遗传分析中的应用

DNA分子标记技术很多,基本都是建立在RFLP、PCR和重复顺序的基础上的。本文重点介绍了限制性片段长度多态性（RFLP）标记、随机扩增多态性DNA（RAPD）标记、微卫星DNA（STR）标记、DNA指纹（DFP）标记、扩增片段长度多态性（AFLP）标记等几种重要的DNA分子标记技术的定义、结构、分布、组成、保守性、优点及丰富的多态性等。并重点介绍了微卫星DNA（STR）标记在分子遗传监测、遗传多样性分析和遗传血缘关系及个体识别等领域的应用。     

鸡的遗传多样性的研究方法及研究进展

遗传多样性是生物学研究中的一个重要领域,研究鸡的遗传多样性,不仅能加强生物多样性的保护。同时对起源进化、分类鉴定及遗传育种等都有重要的意义。本文对目前DNA水平鸡的遗传多样性的研究方法和研究进展进行了详细的阐述。重点介绍了DNA分子标记的特征;概括了在鸡遗传多样性分子标记的方法,包括微卫星分子标记(SSR)、扩增片段长度多态性(AFLP)、随机扩增多态性标记(RAPD)、限制性片段长度多态性标记(RFLP)和单核苷酸多态性标记(SNP)。本文综述了最近有关鸡DNA水平的遗传多样性的研究方法在系统学、遗传结构、生物地理等研究中的应用情况;提出在研究鸡遗传多样性时,可根据研究的目的,选择合适的方法。     

分子标记技术的发展及应用

介绍了几种应用前景较广的分子标记,如基于DNA杂交技术的分子标记:限制性片段长度多态性(RFLP)和DNA可变串联重复数标记(VNRT);基于PCR技术的分子标记:随机扩增多态性 DNA(RAPD)、酶切扩增多态性(CAPS)、扩增片段长度多态性(AFLP)、微卫星DNA(SSR)和DNA单链构象多态性(SSCP);以及新兴的第3代分子标记,即基于DNA芯片技术的分子标记:单核苷酸多态性(SNP)等。分别阐述了它们的原理、方法步骤与优缺点、应用注意事项和适用范围,同时概述了它们在生物学研究中的应用和进展。     

草莓DNA分子标记及其应用

综述了限制性长度多态性(RFLP)、随机扩增多态性DNA(RAPD)、扩增片段长度多态性(AFLP)、简单重复序列(SSR)等不同类型分子标记在草莓指纹图谱构建、品种鉴别、遗传多样性、进化、遗传作图以及相关性状的标记等方面的应用,分析了草莓分子标记研究中的关键问题,提出了今后研究方向。     

扩增片段长度多态性( AFLP) ——一种新的分子标记技术

AFLP(扩增性片段长度多态性)是一种新的DNA分子标记。与RFLP、RAPD相比,AFLP具有在一次试验中可同时观察到大量的限制性片段的优点。本文阐述了AFLP的原理和方法,综述了AFLP目前在植物遗传育种研究中的应用进展,并对AFLP技术在植物遗传育种中的应用前景提出了初步设想。     

遗传标记及其在作物品种鉴定中的应用

本文评述了用于作物品种鉴定的形态标记（morphological markers）、细胞标记（cytological markers）、生化标记（biochemical markers）、分子标记（molecular markers）的优缺点。重点评述了分子标记在作物品种鉴定中的应用。文中除对蛋白质电泳指纹图谱——同工酶和贮藏蛋白（包括醇溶性蛋白、清蛋白、谷蛋白、球蛋白等）电泳产生的指纹图谱的应用外,较详细地介绍了近年来DNA指纹图谱技术;包括限制片段长度多态性（restriction fragment length polymorphism,简称RFLP）、随机扩增多态性DNA (random amplified po lymorphic DNA,简称RAPD)、小卫星DNA（minisatellite DNA）、微卫星DNA（microsatellite DNA）,简单重复序列间扩增（intersimple sequence repeats,简称ISSR）,扩增片段长度多态性（amplified fragment length polymorphism,简称AFLP）以及CAPS (cleaved amplified polymorphic sequences)和SNPS (single nucleotide polymorphisms)对作物品种鉴定和新品种登记,品种纯度和真实性的检验以及品种间亲缘关系的探讨和在分类研究中的贡献等。     

DNA分子标记技术在濒危物种保护中的应用

近20年来,随着分子生物学技术的迅猛发展,涌现出一批高效、可靠的DNA分子标记技术.本文论述了限制性片段长度多态性、微卫星DNA、随机扩增多态性DNA、扩增片段长度多态性等DNA分子标记技术的基本原理及技术特点;同时,介绍了DNA分子标记在濒危物种种群遗传学研究、致危因素分析及保护策略的制定等保护生物学方面的应用.     

DNA指纹技术在污染土壤生态毒理诊断中的应用

生物标记物能在细咆或分子水平上指示暴露．效应关系,是进行污染土壤生态毒理诊断的主要技术手段之一。随着分子生物学技术的飞速发展,出现了一系列以聚合酶链式反应为基础的、在分子水平上检测污染物质导致的生物体DNA损伤的DNA指纹技术。DNA指纹技术的主要类型有：随机扩增多态性DNA（RAPD）、聚合酶链式反应．单链构象多态性（PCR-SSCP）、扩增片段长度多态性（AFLP）、任意引物聚合酶链式反应（AP—PCR）、差异显示反转录聚合酶链式反应（DDRT）、短DNA重复序列（SSR）及限制片段长度多态性（RFLP）等。这些技术与检测基因突变、染色体畸变和损伤为主的一系列经典研究方法如彗星分析、微核实验等相比具有简便、快速、灵敏等优点。本文着重介绍了随机扩增多态性DNA、聚合酶链式反应．单链构象多态性、扩增片段长度多态性3种重要的DNA指纹技术在污染土壤诊断中的应用。     

RAPD技术在植物遗传育种研究中的应用进展

RAPD技术是一种随机扩增多态性DNA的方法,操作简单、快捷且经济,可从分子水平提供直接的遗传证据。RAPD技术在植物遗传育种中的应用如下：1）遗传图谱的构建;2）分子标记辅助选择育种;3）外源染色体片段的鉴定和标记;4）遗传关系与遗传多样性的研究;5）体细胞杂种的鉴定。     

扩增片段长度多态性(AFLP)——一种新的分子标记技术

ＡＦＬＰ（扩增性片段长度多态性）是一种新的ＤＮＡ分子标记。与ＲＦＬＰ、ＲＡＰＤ相比,ＡＦＬＰ具有在一次试验中可同时观察到大量的限制性片段的优点。本文阐述了ＡＦＬＰ的原理和方法,综述了ＡＦＬＰ目前在植物遗传育种研究中的应用进展,并对ＡＦＬＰ技术在植物遗传育种中的应用前景提出了初步设想。     

用GGE双标图分析甘蔗品种性状稳定性及试点代表性

算术平均法经常被用于评估甘蔗品种产量的稳定性和适应性,并用方差分析来估计区域试验的试验误差.然而,地点和年份的差异使品种的差异难以得到准确评估.为客观评价甘蔗品种的稳定性和适应性,本研究采用GGE双标图对2008-2009年我国甘蔗区域试验5个试点中的7个甘蔗品种试验数据进行分析.结果表明： 福农30号为蔗茎产量高且稳产性高的品种,粤甘18号为含糖量高且性状稳定的品种,福农28号和云蔗99 91为高蔗糖分且性状稳定的品种,粤甘16号的蔗茎产量和含糖量最高,但稳定性一般;在各试点中,福建漳州和广东遂溪的代表性和鉴别力较强.GGE双标图分析为客观评价甘蔗参试品种的丰产性和稳定性提供了直观、有效的手段,为甘蔗新品种的鉴定与推广提供了科学依据.     

绵羊基因组研究进展

过去几年中,家畜基因组计划取得了巨大进展。已经构建了猪、鸡、牛、绵羊、马、鹿的遗传图谱,其遗传标记间距在5～20cM。这些图谱对于家畜中与重要经济性状相关的基因或遗传标记的鉴定非常重要。该文从绵羊的基因图谱、比较图谱、重要经济性状基因及QTL定位方面对绵羊基因组的研究进展作了简要阐述。 Abstract:During the last few years,advances in livestock genome projects have been remarkable.Species-specific genetic maps exist for pig,chicken,cattle,sheep,horse,and deer with marker intervals of 5 to 20 cM.These maps have been essential for the identification of genes and genetic markers associated with importantly economic traits in livestock.In this paper,advances of gene map,comparative map,the genes for importantly economic traits and quantitative trait loci (QTL) mapping were briefly introduced in sheep.     

质体基因工程中选择标记基因研究进展

与细胞核基因工程相比,质体基因工程能更安全、精确和高效地对外源基因进行表达,作为下一代转基因技术已广泛用于基础研究和生物技术应用领域。与细胞核基因工程一样,质体基因工程中也需要合适的选择标记基因用于转化子的筛选和同质化,但基于质体基因组的多拷贝性和母系遗传特点,转化子的同质化需要一个长期的筛选过程,这就决定了质体基因工程中选择标记基因的选择标准将不同于细胞核基因工程中广泛使用的现行标准。目前,质体基因工程的遗传转化操作中使用较多的是抗生素选择标记基因,出于安全性考虑,需要找到可替换、安全的选择标记基因或有效的标记基因删除方法。本文在对质体基因工程研究的相关文献分析基础之上,对主要使用的选择标记基因及其删除体系进行了综述,并对比了其优缺点,同时探讨了质体基因工程中所使用的报告基因,以期为现有选择标记基因及其删除体系的改进和开发提供一定参考,进一步推动质体基因工程,尤其是单子叶植物质体基因工程的发展。     

iDArTs: increasing the value of genomic resources at no cost

For many years, genetic markers have been the building blocks in assembling genomic knowledge. Improved technology and methods for collecting marker data have increased accuracy, increased throughput, and reduced cost. However, common genotyping technology still produces far fewer markers in plant species than in animals and humans. We propose a new type of genetic marker based on the Diversity Arrays Technology (DArT) genotyping system for organisms lacking a reference genetic sequence. These markers are based directly on microarray probe intensity profiles and hence are called iDArTs. They require no additional genotyping beyond screening with a DArT array. Since standard methods of genetic analysis cannot be used with these continuous markers, we develop novel methods for the common bi-parental experimental designs doubled haploids, recombinant inbred lines, and backcrosses. These enable the augmentation of genetic maps with iDArTs and permit quantitative trait locus mapping with both discrete and continuous markers. We use simulation to demonstrate the power of this approach for marker mapping. In addition, we construct maps and perform linkage analysis for these DArT genotypes using the doubled haploid progeny lines from a cross between the wheat cultivars Chara and Glenlea. These methods allow access to a previously untapped genetic resource by extracting additional information from the raw data. With no additional genotyping cost, we are able to double the number of markers mapped and thereby increase genome coverage.     

InDel标记的研究和应用进展

InDel是指在近缘种或同一物种不同个体之间基因组同一位点的序列发生不同大小核苷酸片段的插入或缺失(insertion-deletion), 是同源序列比对产生空位(gap)的现象。InDel在基因组中分布广泛、密度大、数目众多。InDel多态性分子标记是基于插入/缺失位点两侧的序列设计特异引物进行PCR扩增的标记, 其本质仍属于长度多态性标记, 可利用便捷的电泳平台进行分型。InDel标记准确性高、稳定性好, 避免了由于特异性和复杂性导致的后续分析模糊。此外, InDel标记能扩增混合DNA样品和高度降解的微量DNA样品, 并进行有效分型。InDel标记目前已开始应用于动植物群体遗传分析、分子辅助育种以及人类法医遗传学、医学诊断等领域。随着位于功能基因上InDel标记的开发, 结合染色体步移和基因精细定位, 可将这些标记应用于相关物种经济性状的功能基因的筛选, 有利于优良基因的进一步开发和利用。     

几种基于PCR的分子标记在甘薯遗传多样性研究中的应用

遗传多样性是甘薯品种遗传改良的基础。由于分子标记具有数量极大、不受环境及基因表达与否的限制、多为共显性、不影响生物性状表现等优点,现已在甘薯遗传多样性研究中得到广泛应用。本文比较了RAPD、AFLP、SSR、ISSR和SRAP等几种基于PCR的分子标记方法,分别从遗传差异和亲缘聚类分析两方面,对它们在甘薯遗传多样性研究中的应用进行了综述。对比分析表明ISSR是一种共显性、成本较低、重复性好、多态性较高且非常有发展前途的分子标记,并已经被广泛应用到甘薯遗传多样性、物种亲缘关系、系统分类和辅助育种研究中。     

Discordance in the distribution of markers of different inheritance systems (nDNA,mtDNA, and Chromosomes) in the superspecies complex <Emphasis Type="Italic">Mus musculus</Emphasis> as a result of extensive hybridization in primorye

The genetic structure of eight Mus musculus L. populations in Primorskii krai was studied with the use of taxon-specific markers of different inheritance systems: nDNA (RAPD), mtDNA (D-loop), and chromosomes. The results obtained demonstrate that although the compared nuclear marker characteristics (nDNA and chromosomes) have the same basis they are not linke with each other and, moreover, are often mutually inconsistent. Discordance in the inheritance of the marker characteristics in most of the animals studied is a result of extensive hybridization involving two to four house mouse subspecies. To identify taxonspecific nuclear markers revealed by RAPD, some RAPD PCR products were cloned, and their localization on chromosomes was determined. It was found that some fragments similar in size consist of two different comigrating sequences that are localized on different chromosomes and belong to different subspecies. All sequenced anonymous markers are localized in protein-coding genes. The functions of genes containing the marker sequences have been established. Differences in the taxon-specific RAPD fragments are associated with changes in the structure of important functional genes, and this can be considered as a significant genetic marker.     

A comparison of biallelic markers and microsatellites for the estimation of population and conservation genetic parameters in Atlantic salmon (Salmo salar)

Biallelic markers such as single nucleotide polymorphisms (SNPs) and insertion/deletion polymorphisms have become increasingly popular markers for various population genetics applications. However, the effort required to develop biallelic markers in nonmodel organisms is still substantial. In this study, we compared the estimation of various population genetic parameters (genetic divergence and structuring, isolation-by-distance, genetic diversity) using a limited number of biallelic markers (in total 7 loci) to those estimated with 14 microsatellite loci in 21 Atlantic salmon (Salmo salar) populations from northern Europe. Pairwise FST values were significantly correlated between biallelic loci and microsatellite datasets, as was overall heterozygosity when both anadromous and nonanadromous populations were analyzed together. However, when the anadromous and nonanadromous samples were analyzed separately, only genetic divergence correlations remained significant. Biallelic markers alone were not sufficient for reliable neighbor-joining clustering of populations but gave highly similar isolation-by-distance signals when compared with microsatellites. Finally, although several population prioritization measures for conservation exhibited significant correlation between different marker types, the specific populations highlighted as being most valuable for conservation purposes varied depending on the marker type and conservation criteria applied. This study demonstrates that a relatively small set of biallelic markers can be sufficient for obtaining concordant results in most of the analyses compared with microsatellites, although estimates of genetic distance are generally more concordant than estimates of genetic diversity. This suggests that a relatively small number of biallelic markers can provide useful information for various population genetic applications. However, we emphasize that the use of much higher number of loci is preferable, especially when the genetic differences between populations are subtle or individual multilocus genotype-based analyses are to be performed.     

Discordance in the distribution of markers of different inheritance systems (nDNA, mtDNA, and chromosomes) in superspecies complex Mus musculus as a result of extensive hybridization in Primor'e

The genetic structure of eight Mus musculus L. populations in Primorskii krai was studied with the use of taxon-specific markers of different inheritance systems: nDNA (RAPD), mtDNA (D-loop), and chromosomes. The results obtained demonstrate that although the compared nuclear marker characteristics (nDNA and chromosomes) have the same basis they are not linke with each other and, moreover, are often mutually inconsistent. Discordance in the inheritance of the marker characteristics in most of the animals studied is a result of extensive hybridization involving two to four house mouse subspecies. To identify taxon-specific nuclear markers revealed by RAPD, they were cloned and sequenced, and their localization on chromosomes was determined. It was found that some fragments similar in size consist of two different comigrating sequences that are localized on different chromosomes and belong to different subspecies. All sequenced anonymous markers are localized in protein-coding genes. The functions of genes containing the marker sequences have been established. Differences in the taxon-specific RAPD fragments are associated with changes in the structure of important functional genes, and this can be considered as a significant genetic marker.