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1.
微卫星分子标记分析四川绵羊群体遗传多样性   总被引：2，自引：0，他引：2  
为探究四川省6个绵羊群体的遗传多样性,实验应用12个微卫星标记计算基因频率、有效等位基因数、杂合度及多态信息含量来评估群体内遗传多样度,通过遗传距离聚类图、群体结构推测图、主成分分析及群体间分子方差分析来评估群体间遗传关系。结果表明:6个绵羊群体在12个微卫星位点的平均有效等位基因数为3.006~3.176,平均多态信息含量变化为0.559~0.612,平均期望遗传杂合度为0.610~0.670;6个绵羊群体间的遗传关系与地理分布情况及育成史实不完全一致,但遗传距离聚类图、群体结构推测图和主成分分析结果均显示,6个绵羊群体中布拖黑绵羊类群与贾洛绵羊类群遗传关系更近;6个绵羊群体间方差组分F统计量结果为0.112 39,处于中度分化水平。  相似文献   

2.
基于SRAP和SSR分子标记分析了青藏高原东南缘8个老芒麦自然居群遗传变异及群体遗传结构,获得下述结果:1)16对SRAP引物在90个单株中共扩增出384条可统计条带,其中多态性条带334条,占86.98%;16个SSR位点共检测出等位变异221个,平均每个位点13.8个,其中具有多态性的位点数192个,占86.88%。2)2种分子标记检测到老芒麦居群水平的基因多样性(He)分别为0.1092和0.1296,而物种水平的基因多样性达0.2434和0.3732。3)基于2种标记的Nei氏遗传分化指数Gst(0.5525和0.5158)表明老芒麦居群出现了较大程度的遗传分化,居群间的基因流非常有限,分别为0.4050和0.4694,老芒麦的遗传变异主要分布在居群间,居群内变异相对较小,Shannon多样性指数和分子方差变异(AMOVA)分析显示了相似的结果。4)基于聚类分析结果表明各居群间存在较为明显的地理分化,8个居群分化为采集地范围内的南、北和中部3个分支。通过对老芒麦遗传多样性和遗传结构的分析提出了对该物种遗传多样性的保护策略。  相似文献   

3.
选用10对微卫星引物分析了黄羽肉鸡A、B、C3个品系的遗传结构和差异,并对微卫星标记所计算的个体间遗传距离与C×B、C×A杂交后代的初生至8周龄体重的杂种优势和杂种优势率进行了相关分析。结果表明,10个微卫星标记中有9个表现出多态性,多态信息含量(PIC)和群体杂合度(Heterozigosity)分别为0·4400和0·6811,各品系、各微卫星基因座上都表现出一定差异。利用9个多态微卫星标记计算得出的亲本个体间的遗传距离与后代杂种优势率间多数没有显著的相关(P>0·05),仅C×B组合中亲本个体间平均遗传距离与第8周龄体重杂种优势和杂种优势率间相关显著(P<0·05)。  相似文献   

4.
为了解中国双峰驼群体的遗传多样性及不同种群间的遗传进化关系,本研究采用微卫星标记技术,对中国阿拉善驼、青海驼、南疆驼、北疆驼、肃北驼、苏尼特驼6个双峰驼群体进行了遗传多样性分析。通过计算杂合度（H）、多态信息含量（PIC）、有效等位基因（Ne）、Shannon信息指数等分析群体内遗传变异,通过计算F-统计量、基因流、遗传分化系数、遗传距离等分析群体间遗传进化关系。结果显示,10个微卫星位点共检测到了89个等位基因,平均每个位点检测到8.9个等位基因;所有位点均属中高度多态位点（YWLL08除外）,平均PIC值在0.488~0.752之间;6个群体观测杂合度值（0.355~0.448）都低于期望杂合度值（0.643~0.703）;几乎所有位点的Shannon指数都>1,且处于哈代-温伯格不平衡状态（P< 0.05）。群体间遗传分化系数Fst值为0.059,处于较低程度的中等分化状态; 6个双峰驼群体的平均Fis值均为正值,说明6个双峰驼群体都存在不同程度的近交。基于标准遗传距离DS和遗传距离DA进行聚类分析,南疆驼和北疆驼聚为一支,阿拉善驼、青海驼、肃北驼、苏尼特驼4个群体聚为一支。研究表明,中国双峰驼遗传多样性丰富,群体内遗传变异较大,存在一定近交现象;群体间存在着一定的基因流动,群体间的分化主要由群体内的遗传变异造成;6个群体分为2个类群。  相似文献   

5.
In order to understand the genetic diversity of Bactrian camel and the genetic evolutionary relationships between different populations,the genetic diversity of Alashan camel, Qinghai camel, Nanjiang camel, Beijiang camel, Subei camel and Sunite camel populations in China were analyzed using 10 microsatellite markers. By calculating heterozygosity (H), polymorphism information content (PIC), effective allele (Ne), Shannon information index, the genetic variation within populations were analyzed. By calculating the F-statistics, gene flow, genetic differentiation coefficient and genetic distance to analyze the genetic relationship between populations. The results showed that 89 alleles were tested at the 10 microsatellite loci,8.9 alleles were tested at every locus in average. All loci were medium-highly polymorphic loci (except YWLL08),the average PIC of the Bactrian camel population was between 0.488 to 0.752. The observed heterozygosity (0.355 to 0.448) of 6 Bactrian camel populations was lower than the expected heterozygosity (0.643 to 0.703). Almost all loci Shannon index was greater than 1,and most of loci were in Hardy-Weinberg disequilibrium. The genetic differentiation coefficient between groups (Fst) value was 0.059 and in the low degree of moderately differentiated state. The average Fis values of 6 Bactrian camel populations were positive which suggested 6 Bactrian camel populations had different levels of inbreeding. The standard genetic distance (DS) and genetic distance T (DA) clustering analysis showed that the Nanjiang camel and Beijiang camel jointed as one group, the Alxa camel, Qinghai camel, Subei camel, Sunite camel jointed as the other group. Research showed that Chinese Bactrian camel was abundant in genetic diversity, genetic variation within population was larger, and there was a phenomenon of inbreeding. There was a certain gene flow between populations, the differentiation of populations were mainly caused by genetic variation within population. 6 Chinese Bactrian camel populations were divided into two groups.  相似文献   

6.
俞靓  井赵斌  程积民 《草地学报》2012,20(3):512-517
利用ISSR分子标记,对采自陕西省不同地区的5个本氏针茅(Stipa bungeana)自然种群进行遗传变异及群体遗传结构分析,旨在探讨本氏针茅遗传变异产生的分子生态机理,为其资源保护提供理论依据。在100个供试单株中,采用15条ISSR引物共扩增出223条可统计条带,其中多态性带182条,多态性位点比率为81.61%,Nei’s基因多样性(H)为0.1887,Shannon 信息指数(I)为0.2975,各种群之间存在较高的多态性。种群间的遗传变异为63.01%,种群内的遗传变异为36.99%,遗传分化系数φst 为0.6300,种群间的基因流(Nm)为0.1468,表明本氏针茅遗传分化程度较高,遗传变异主要分布在种群间,而种群内变异相对较小,且各种群间的基因交流非常有限。  相似文献   

7.
为筛选多态性丰富的羊草叶绿体非编码区片段,本研究以9个不同地理位置的羊草居群为材料,通过对12个叶绿体非编码区DNA片段测序及其序列间变异分析试图从中找出有遗传差异的叶绿体DNA(cpDNA)片段,并利用有多态性的cpDNA片段进行遗传多样性分析。结果表明,序列ndhF-rpl32、trnL-trnF、trnC-ycf6、aptI-aptH具有比较丰富的变异,可作为下一步研究野生羊草群体遗传学和谱系地理学较为理想的分子标记。在37个羊草个体4条非编码区片段的合并序列中,共检测到15种单倍型,单倍型多态性(Hd)为0.928,核苷酸多态性(Pi)为0.00101;遗传分化指数(Fst)为0.58884,基因流(Nm)为0.17,基因流较小;中性检验Tajima’s D(-1.08542)和Fu’s Fs(-5.301)均为负值,且差异不显著(P>0.10),推测羊草遵循中性进化理论,可能经历过种群扩张;AMOVA结果显示,65%的分子变异出现在居群间,35%出现在居群内;Mantel检验得到,遗传距离与地理距离具有显著相关性(r=0.449,P<0.05);居群分化值Nst 0.386(0.1865)大于Gst 0.234(0.1506),差异显著(P<0.05),表明羊草居群存在分子谱系地理结构。通过系统发育树分析得到,羊草15个单倍型分为两大分支,H2和H10聚为一支,它们与别的居群个体亲缘关系较远,其余单倍型聚为另一支;单倍型网络图显示,H2和H12、H10和H12亲缘关系较远,与系统发育树分析结果基本一致。本研究为羊草的种质资源保护、谱系地理学研究等工作奠定了基础。  相似文献   

8.
闽南牛遗传多样性及其系统地位的研究   总被引：1，自引：0，他引：1  
以中心产区简单随机抽样法在福建省漳州市漳浦县霞关乡抽取闽南牛64头,采集血样,按常规方法分离血浆和血细胞,冷冻后带回实验室-20℃保存备用。用垂直平板聚丙烯酰胺凝胶电泳(PAGE)和水平淀粉凝胶电泳技术检测21个编码血液蛋白(酶)的结构基因座的基因频率,同时引用国内外13个群体7个相同座位的研究资料,进行聚类分析,结果表明:在所检测的21个基因座中,有10个存在多型,多态位点百分比为47．62％,群体内遗传变异水平相对较高,平均杂合度为0．1593;闽南牛与东南亚牛种亲缘关系较近,证实了闽南牛是由南方黄牛和瘤牛的混血种,但可能不含有斑腾牛或巴厘牛的血统。目前应扩大保种群的数量,以维持群体内遗传传多样性。  相似文献   

9.
应用SSR分子标记,对河南省15个居群共288份狗牙根材料进行遗传多样性及群体遗传结构分析,结果表明,10对引物共扩增出173条条带,其中163条为多态性条带,多态性条带百分率为94.29%,表明河南省狗牙根具有丰富的多态性。15个居群间的遗传分化系数为0.3857,即发生在居群间的遗传变异达到38.57%,大部分的遗传变异发生在居群内部,居群间基因流为0.7964,居群之间存在一定程度的基因交流。不同居群间遗传一致度的变化范围是0.746~0.964,平均为0.767。15个居群间的UPGMA聚类分析结果表明居群间没有完全按照地理来源进行聚类,遗传距离和地理距离矩阵之间的Mantel检验结果表明狗牙根居群间的遗传距离与地理距离之间无相关性。288份狗牙根材料之间的遗传距离为0.0173~0.5205,平均为0.3113,UPGMA聚类结果将所有材料分为3组。基于Structure软件的群体遗传结构分析结果表明,可将288份狗牙根材料分为2个亚群和一个混合型群体,与288份材料的UPGMA聚类结果基本一致,由此可判断两个亚群的遗传背景单一,混合型群体存在一定的种质基因渗透,遗传背景较为复杂。  相似文献   

10.
The genetic diversity in two buffalo populations of northern India, the Bhadawari and the Tarai was assessed using a set of 22 heterologous (bovine) microsatellite markers. The average number of alleles across all loci in both populations was found to be 4.7, indicating that this set of 22 bovine microsatellite markers could be used to study genetic variation in buffalo species also. The overall polymorphic information content (PIC) value for these markers was 0.54. The average observed and expected heterozygosities for both populations were 0.59 and 0.64, respectively. Common alleles with varying allele frequencies in both populations also represented the genetic variability existing between Bhadawari and Tarai buffaloes. However the θ estimates for population differentiation indicated low levels of differentiation between the two populations. This was further supported by the low genetic distance (0.155) between Bhadawari and Tarai, which was calculated using Nei's standard genetic distance method. The present study on Bhadawari and Tarai populations represents a much‐needed preliminary effort that could be extended to other local buffalo populations of India as well.  相似文献   

11.
俞靓  井赵斌  魏琳  程积民 《草业科学》2012,29(12):1876-1882
利用ISSR分子标记,分析宁南山区6个本氏针茅（Stipa bungeana）自然种群的遗传分化及其群体遗传结构,旨在探讨本氏针茅遗传变异产生的分子生态机理,为其资源保护提供理论依据。主要结果如下,在本氏针茅6个种群中,15条ISSR引物共扩增出244条可统计条带,其中多态性条带239条,多态性位点比率（PPB）为97.95%,Nei’s基因多样性指数（H）为 0.254 4,Shannon信息指数（I）为0.396 6,各种群之间具有较高的遗传差异。分子方差分析（AMOVA）表明本氏针茅遗传变异的58.06%发生在种群内,41.94%的遗传变异发生在种群间。Mantel检测结果显示本氏针茅6个种群间的遗传距离和地理距离之间均无显著相关性。  相似文献   

12.
旨在揭示康西草原马匹的品种来源以及群体遗传结构。本研究采集了当地60匹健康状况良好、体重适中、3～6岁之间不区分公母马的血液样品,试验分为6个种群并以纯血马等4个国外马品种、1个我国地方马品种作为对照， 通过设计引物并提取基因组DNA结合微卫星扩增法对染色体上12个微卫星位点的等位基因进行检测，并对各种群遗传多样性参数、群体分化指数、瓶颈效应以及群体结构进行分析。试验按照群体个数为依据分为6组，每组1个重复，每个重复以该组样本量为标准。分析6个种群马的遗传参数结果表明，其中共检测到221个等位基因,平均Shannon指数为1.691；有效等位基因数(Ne)为3.649～5.397；期望杂合度(He)为0.681～0.798；观测杂合度(Ho)为0.632～0.780；平均多态信息含量(PIC)为0.643～0.772。这些结果表明，6个群体都具有很高的遗传多样性。通过微卫星DNA位点的连锁不平衡及哈迪-温伯格平衡分析发现， 大多数位点的P值都大于校正值(P=0.006 5)，表示较多位点都处于哈迪-温伯格及连锁平衡状态。各群体间群体分化系数(Fst)表明，群体间分化程度较低(Fst<0.15)。基于Nei’s遗传距离与地理距离之间Mantel相关性检验显示二者之间呈现正相关性(R=0.502)，但未达到显著水平(P=0.310)；各马匹种群瓶颈效应分析表明，P值极显著(P(IAM)<0.01)说明该地区的马群体受到过瓶颈效应的影响且该马群体历史上数量有大规模的减少。通过 FCA因子分析、基于Nei’s标准遗传距离UPGMA树状图以及Structure贝叶斯聚类分析发现，该地区马种群与纯血马和温血马聚为一类，说明该种群最有可能主要来源于温血马和纯血马。这些结果揭示，康西草原地区马匹具有较高的遗传多样性，该地马群体的血统与纯血马和温血马相近，这为当地马遗传资源评估以及开发利用打下了坚实的基础。  相似文献   

13.
Seven microsatellite markers were used to study genetic diversity of three Egyptian (Egyptian Baladi, Barki and Zaraibi) and two Italian (Maltese and Montefalcone) goat breeds. The microsatellites showed a high polymorphic information content (PIC) of more than 0.5 in most of the locus-breed combinations and indicated that the loci were useful in assessing within- and between-breed variability of domestic goat (Capra hircus). The expected heterozygosity of the breeds varied from 0.670 to 0.792. In the geographically wider distributed Egyptian Baladi breed there were indications for deviations from random breeding. Analysis of genetic distances and population structure grouped the three Egyptian goat breeds together, and separated them from the two Italian breeds. The studied Mediterranean breeds sampled from African and European populations seem to have differentiated from each other with only little genetic exchange between the geographically isolated populations.  相似文献   

14.
The Namaqua Afrikaner is an endangered sheep breed indigenous to South Africa, primarily used in smallholder farming systems. Genetic characterization is essential for the breed’s conservation and utilization. In this study, a genetic characterization was performed on 144 Namaqua Afrikaner sheep kept at the Karakul Experimental Station (KES), Carnarvon Experimental Station (CES), and a private farm Welgeluk (WGK) using 22 microsatellite markers. The mean number of alleles observed was low (3.7 for KES, 3.9 for CES, and 4.2 for WGK). Expected heterozygosity values across loci ranged between 46 % for WGK, 48 % for KES, and 55 % for CES, indicating low to moderate genetic variation. The analysis of molecular variance revealed that 89.5 % of the genetic variation was due to differences within populations. The population structure confirmed the differentiation of three clusters with high relationships between the CES and WGK populations. In the population structure comparison with Pedi and South African Mutton Merino sheep, limited hybridization between the Namaqua Afrikaner sheep and both of these breeds was observed. The results of this study will serve as a reference for genetic management and conservation of Namaqua Afrikaner sheep.  相似文献   

15.
试验旨在研究浦东白猪现存群体的遗传多样性及其繁殖性能变化的原因。利用全基因组范围内的遗传标记（SNPs）,对比6个太湖流域地方品种及3个西方引进品种,对浦东白猪的遗传多样性进行了分析。同时利用落入繁殖候选基因内的SNPs,分析了群体的多样性及结构。结果显示,相较于本研究中所选择的太湖流域地方品种及西方引进品种,浦东白猪的遗传多样性较太湖流域地方品种低;除枫泾猪外,浦东白猪繁殖相关SNPs的多态性标记的比例、期望杂合度最低,等位基因丰度仅高于杜洛克猪;主成分分析（PCA）结果揭示浦东白猪繁殖相关SNPs位点仍具有其群体独特性。研究结果揭示了浦东白猪现存群体遗传多样性较低,繁殖性能的退化可能是由于一些有利等位基因的灭绝、繁殖相关基因多态性及个体杂合性的降低所致。但是浦东白猪仍然携带一定数量的有利等位基因且依旧具有其群体独特性,暗示浦东白猪仍具有较高的保种价值。本研究为浦东白猪后期的选育、保种和开发利用提供了一定的参考。  相似文献   

16.
This study was aimed to investigate the genetic diversity and the reason for the degradation of the reproductive performance of Pudong White pig. The genetic diversity of Pudong White pig, six Taihu pig breeds and three Western pig breeds were analyzed based on the genome-wide SNPs.The genetic diversity and population structure of these pig breeds were also explored based on the SNPs related to reproductive traits. The results showed that Pudong White pig displayed a lower level of the genetic diversity than the Taihu area pig breeds. For the reproductive-related loci, except for Fengjing pig, Pudong White pig displayed the lowest propotion of polymorphic markers, expected heterozygosities and allelic richness (excluded Duroc pig). The result of PCA showed that Pudong White pig displayed its uniqueness in the reproductive-related SNPs. With the comparsion of Taihu pigs and Western populations, Pudong White pig displayed a lower level of the genetic diversity and more homozygous reproductive-related loci. Nevertheless, a certain number of favorable alleles were still harbored in Pudong White pig, which might result high heterosis in the offsprings. In conclusion, the results of this study might provide some valuable information for the breeding, conservation and utilization of this breed.  相似文献   

17.
The objective of this study was to evaluate the genetic structure of Mexican Criollo cattle populations using microsatellite genetic markers. DNA samples were collected from 168 animals from four Mexican Criollo cattle populations, geographically isolated in remote areas of Sierra Madre Occidental (West Highlands). Also were included samples from two breeds with Iberian origin: the fighting bull (n = 24) and the milking central American Criollo (n = 24) and one Asiatic breed: Guzerat (n = 32). Genetic analysis consisted of the estimation of the genetic diversity in each population by the allele number and the average expected heterozygosity found in nine microsatellite loci. Furthermore, genetic relationships among the populations were defined by their genetic distances. Our data shows that Mexican cattle populations have a relatively high level of genetic diversity based either on the mean number of alleles (10.2-13.6) and on the expected heterozygosity (0.71-0.85). The degree of observed homozygosity within the Criollo populations was remarkable and probably caused by inbreeding (reduced effective population size) possibly due to reproductive structure within populations. Our data shows that considerable genetic differentiation has been occurred among the Criollo cattle populations in different regions of Mexico.  相似文献   

18.
蒙古冰草遗传多样性的等位酶分析   总被引：18，自引：3，他引：15  
采用聚丙烯酰胺凝胶电泳技术检测了内蒙古中东部地区蒙古冰草6个天然居群和2个栽培品种的遗传多样性和居群结构，12个酶位点的多态位点百分率为67.71%，基因多样性指数（He)为0.285，显示出了较高的遗传多样性，从遗传多样性的分布格局来看，8个居群的遗传分化系数Gsr=0.129，表明在总的遗传变异中，只有12.9%的变异存在于居群间，而87.1%的变异存在于居群内，同时，6个天然居群的总基因多样度（HT=0.439)和基因分化系数（GST=0.032)也大于2个栽培品种的相应值（HT=0.423,GST=0.010)。UPGMA聚类分析的结果表明，蒙古冰草居群间的遗传分化与生态环境因子间有着密切的相关性。  相似文献   

19.
利用SRAP标记对来自西藏境内的4个光核桃自然居群的遗传多样性和群体遗传结构进行了分析和评价。选用20对引物对4个居群的70份材料进行扩增,检测到338个多态位点。在居群水平上,多态位点百分率为63.96%,Nei’s基因多样性和Shannon’s信息指数分别为0.194 3和0.295 5。在物种水平上,多态位点百分率为89.89%,Nei’s基因多样性和Shannon’s信息指数分别为0.246 0和0.383 9。居群间的遗传分化系数为0.170 9,居群间的基因流为1.213 0。UPGMA聚类图中,70个个体未按4个居群各自聚在一起。结果表明,光核桃遗传多样性水平较高,居群间遗传分化较小,居群间的基因交流程度较高。  相似文献   

20.
塔里木马鹿微卫星遗传多样性与产茸量的相关性研究   总被引：1，自引：0，他引：1  
利用7个微卫星遗传标记,采用PCR扩增,12%非变性聚丙烯酰胺凝胶电泳、Sanguinetti银染法显色,对新疆塔里木马鹿亚种遗传多样性进行检测,统计各群体的等位基因组成、平均有效等位基因数(E)和平均基因纯合率(Rh),根据等位基因频率计算出各群体的平均遗传杂合度(h)、多态信息含量(PIC)和群体间的遗传距离,利用分子进化遗传分析软件(MEGA),采用邻结法(NJ)重建系统发生树。根据等位基因频率,利用PHYLIP(3.6)分析软件,采用最大似然法(ML)构建系统发生树,应用自举检验(bootstrap test)估计系统树中节点的自引导值(bootstrap value),并进行了系统发生分析。同时对部分马鹿群体个体基因型与产茸量之间进行了相关分析。结果表明:7个微卫星位点在3个塔里木马鹿中的多态信息含量除BMS2508和Celjp0023没有多态性,以及BM5004为中度多态外,其他4个微卫星均为高度多态,可作为有效的遗传标记用于3个塔里木马鹿群体遗传多样性和系统发生关系的分析。所有马鹿群体的平均PIC为(0.5196)、h(0.5552)和E(2.45),其基因多态性和遗传多样性相对丰富。塔里木马鹿35团群体与沙雅群体的血缘关系及遗传距离近于阿拉尔群体,3个塔里木马鹿群体的系统发育关系基本符合其地理分布和育成史。微卫星位点BM4208的166bp/185bp基因型和微卫星BM888的208bp/208bp基因型可以对塔里木马鹿35团群体高产茸量进行分子遗传标记。  相似文献   

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