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1.
四个鲤鱼种群遗传多样性的AFLP分析   总被引:2,自引:0,他引:2  
本文采用AFLP技术对黑龙江野鲤、黄河鲤、建鲤和荷包红鲤4个鲤鱼种群共96个个体进行了遗传多样性分析。结果显示,8对选择性扩增引物共扩增得到502个位点,其中多态性位点273个,多态性比率为54.38%。同时对4个种群的Shannon多样性指数,Nei's基因多样性等参数进行了分析,结果表明,4个种群的Shannon多样性指数分别为0.2114±0.2705,0.1825±0.2694,0.1888±0.2587和0.1600±0.2426,Nei's基因多样性指数分别为0.1398±0.1872,0.1225±0.1863,0.1235±0.1774和0.1036±0.1636;总基因多样性(Ht)平均值为0.1721±0.0350;种群内基因多样性(Hs)平均值为0.1224±0.0190;基因分化系数(Gst)为0.2892,种群内的基因多样性占总群体的71.08%,种群间为28.92%,而基因流系数(Nm)为1.2291。另一方面,分子方差分析(AMOVA)结果表明,种群平均近交系数(Fst)为0.31191,变异31.19%来自种群间,68.81%来自种群内。4个种群中黑龙江野鲤的种内多态性比例最高,而荷包红鲤种群最低,并且4个鲤鱼种群当前的种质资源良好,具有一定的种群稳定性;建鲤已经开始分化,与亲本荷包红鲤亲缘关系逐渐分化,逐步形成自己稳定的遗传结构。本研究为探讨鲤鱼种群的遗传特性和遗传分化提供参考,也为其种质资源的保护及合理利用提供科学依据。  相似文献   

2.
利用ISSR技术对"全红"瓯江彩鲤(Cyprinus car pio var. color)4个世代群体的遗传结构及其分化进行了分析。筛选的15个ISSR引物从4个世代群体中分别扩增到120、118、101和110条扩增谱带,全部扩增片段长度在200—2500bp之间。根据扩增结果,利用POPGENE version 1.31进行分析,结果表明:4个群体的多态位点比例(P)为51.49%—67.80%,Shannon信息指数(Ho)为0.2176—0.2745之间,并随着世代的增加,选育群体的遗传多样性呈现下降趋势。有70%的遗传变异来自于群体内;结合遗传分化指数Gst、UPGMA聚类分析,证实"全红"瓯江彩鲤4个世代间存在一定程度的遗传分化,即任意两个群体间的遗传分化达到较大的水平(Gst均为0.1588—0.2766)。  相似文献   

3.
对41尾感病和22尾抗病兴国红鲤的308个有效克隆进行测序,获得171条不同的MHCⅡ类α基因编码序列,分属26个不同的等位基因,其中Cyca-DXA24—Cyca-DXA36为新发现的13个等位基因。MHCⅡ类α基因片段的长度为624 bp,包括第1—4个外显子,分别编码信号肽、α1和α2结构域及连接肽/跨膜区。α1结构域的变异明显大于α2结构域,表现在α1结构域中核苷酸和氨基酸变异位点比例(55.16%和79.76%)明显高于α2结构域的变异位点比例(45.96%和68.42%)。α1结构域的PBR区的非同义碱基替换率(dN)与同义碱基替换率(dS)的比值ω(ω=dN/dS)为5.742,远远高于非抗原结合位点(non-PBR)及α2结构域的0.755、0.592,揭示兴国红鲤MHCⅡ类α基因的α1结构域在进化过程中受到正向选择作用。等位基因Cyca-DXA24(P0.01)与兴国红鲤对嗜水气单胞菌的抗性相关,等位基因Cyca-DXA3(P0.05)、Cyca-DXA4(P0.01)、Cyca-DXA6(P0.05)、Cyca-DXA33(P0.05)与兴国红鲤对嗜水气单胞菌的易感性相关。荧光定量PCR结果表明,MHCⅡ类α基因在健康兴国红鲤的肾、肝、鳃等10个组织均能普遍表达。人工感染嗜水气单胞菌后,肾、肝、脾3个组织中的MHCⅡ类α基因的表达量均发生了不同程度的变化,表明MHCⅡ类α分子在兴国红鲤的免疫反应中起到重要作用。  相似文献   

4.
研究基于线粒体DNA细胞色素b (mtDNA Cyt b)基因序列, 对2013—2017年间采自我国长江上游贵州省赤水市和重庆市万州区共161尾岩原鲤(Procypris rabaudi)个体进行了遗传多样性分析。结果表明, 在所有个体序列中, A、T、C、G碱基的平均含量分别为30.2%、27.9%、28.2%和13.7%, (A+T)含量(58.1%)明显大于(G+C)含量(41.9%), 表现出较强的反G偏倚性。161条序列检测到18个变异位点, 定义了15种单倍型, 整体单倍型多样性指数(Hd)、核苷酸多样性指数(Pi)分别为0.590、0.00132; 岩原鲤赤水群体遗传多样性水平低于万州群体; 万州群体的单倍型多样性和核苷酸多样性均呈现逐年降低的趋势, 但是赤水群体的单倍型多样性和核苷酸多样性呈现逐年增加的趋势。基于最大似然法构建的系统发育树和单倍型网络图结果一致, 万州和赤水群体并未形成明显的地理分布格局。Mega 6.0软件计算2个群体之间的遗传距离为0.001。Fst值统计表明, 2个地理群体间Fst值为0.01749 (P>0.05), 群体间没有出现遗传分化现象。两群体间基因交流频繁, 基因流Nm=24.71。分子方差分析(Analysis of Molecular Variance, AMOVA)显示: 98.25%的遗传变异是由群体内产生的。中性检验结果表明万州岩原鲤群体历史上曾发生过种群扩张事件, 时间约为0.15百万年前。岩原鲤群体整体上遗传多样性偏低, 急需提出合理的管理措施, 以加强长江流域岩原鲤物种的资源保护。  相似文献   

5.
采用线粒体细胞色素b基因(Cyt b)序列,分析了采自新疆克孜河3个群体(斯木哈纳SM、牙师YS、卡拉贝利KL)的塔里木裂腹鱼(Schizothorax biddulphi)41尾个体及1个斑重唇鱼(Diptychus maculates)群体(斯木哈纳)23尾个体的种群遗传多样性和遗传结构.结果显示,塔里木裂腹鱼检测到6个碱基变异位点,定义了4种单倍型,平均单倍型多样性指数及核苷酸多样性指数分别为0.525 4和0.001 16.分子变异分析(AMOVA)结果提示,塔里木裂腹鱼的遗传变异全部发生于群体内部;群体间Kimura-2-parameter遗传距离、分化指数(F<,st><0.085 25)和基因流(N<,m>>3.18)都显示3个群体没有种群分化,属于单一种群.斑重唇鱼检测出7个变异位点,定义了8个单倍型,平均单倍型多样性指数与核苷酸多样性指数分别为0.830 1和0.001 13.研究表明,克孜河的塔里木裂腹鱼和斑重唇鱼均处于很低的遗传多样性水平,物种维持力较弱.  相似文献   

6.
为揭示北沙柳(Salix psammophila)的遗传多样性、遗传结构及分化特征,利用叶绿体非编码区序列(trnL-trnF和trnD-trnT)对分布于毛乌素沙地和库布齐沙漠的16个北沙柳居群(339个个体)进行了遗传研究,为北沙柳种子资源库遗传管理、遗传改良、遗传育种及品种选育提供理论依据。结果表明:(1)经trnL-trnF和trnD-trnT片段联合比对获得了1811 bp序列,共有12个核苷酸变异位点(8个简约信息位点,4个变异位点),得到16个单倍型。(2)单倍型多样性指数(Hd)为0.737,核苷酸多样性指数(π)为0.00107;且单倍型H3的分布在所有居群中位于单倍型网络图中心,其余单倍型随机分布于各个居群。(3)AMOVA分析表明,北沙柳cpDNA的变异主要来源于居群内(91.16%),居群间遗传分化程度中等(FST=0.08837),各居群间的基因交流非常频繁(Nm=2.58);遗传分化系数NST(0.085)显著大于GST(0.056,0.01相似文献   

7.
与“全红”瓯江彩鲤体色相关的SRAP及SCAR分子标记   总被引:1,自引:0,他引:1  
利用相关序列扩增多态性(Sequence Related Amplified Polymorphism,SRAP)技术分析"全红"和"粉玉"瓯江彩鲤,筛选与瓯江彩鲤体色相关的分子遗传标记。从88个SRAP引物组合筛选出的12个引物组合共获得扩增条带104个,并筛选出1个SRAP特异扩增带,即"全红"瓯江彩鲤家系SR2,7173 bp带。该条SRAP特异扩增条带经回收、克隆和测序,并将测序结果进行BLAST分析,发现该片段在GenBank中与斑马鱼的POl多蛋白基因和尿红素基因有较高的同源性。根据序列信息分别设计了4对正、反向引物(22—26 bp)。用4对引物分别在"全红"瓯江彩鲤F2和"粉玉"瓯江彩鲤F2群体中进行PCR扩增,仅发现SC-3(154 bp)能够在"全红"瓯江彩鲤群体中特异扩增,而且在"粉玉"瓯江彩鲤F2群体中未出现此扩增带。采用大样本对该SC-3标记进行验证,结果发现,在"全红"瓯江彩鲤群体中呈现阳性,而在"粉玉"瓯江彩鲤群体中为阴性,可以区分这两种群体。因此SC-3标记可以作为"全红"瓯江彩鲤群体一个重要的分子遗传特征指标,为进一步进行分子标记辅助育种奠定了基础。  相似文献   

8.
全面了解中国乌骨鸡的遗传背景有利于保护和开发利用其种质资源。本研究测定了中国12个乌骨鸡品种线粒体细胞色素c氧化酶亚基I (cytochrome c oxidase subunit I, COI)基因, 比较分析其遗传多样性和群体遗传结构。255份乌骨鸡样品共检测到22个变异位点, 占分析位点的3.17%; 核苷酸多样性为0.00142-0.00339, 单倍型多样性为0.380-0.757, 其中略阳乌鸡核苷酸多样性最高, 德化黑鸡最低。检测到7个氨基酸变异位点, 来自6个品种共11个个体。定义了24种单倍型, 其中单倍型H1和H3为12个乌骨鸡品种共享, 出现频率分别为115次和64次; 盐津乌骨鸡单倍型数最多, 广西乌鸡最少。中性检验与错配分析显示实验种群未经历显著的群体扩张事件。分子变异分析显示81.06%的变异来自群体内; 品种间遗传距离为0.002-0.004, 品种间遗传分化系数Fst值为-0.035至0.594, 雪峰乌骨鸡与其他种群间的遗传分化程度最高。邻接树显示, 乌骨鸡未能独立形成分支, 不能从家鸡和红原鸡中有效区分开来。中国乌骨鸡中介网络图将24个单倍型分为3条进化主支, 呈现出一定的品种特异性, 由无量山乌骨鸡、云南盐津乌骨鸡和雪峰乌骨鸡组成单倍型H8、H9、H11、H12游离于这3条进化主支之外。增加其他家鸡和红原鸡COI基因的中介网络图主体结构与中国乌骨鸡的相同。结果表明中国乌骨鸡品种遗传多样性较低, 但品种间遗传分化显著, 可能是从当地家鸡中选育而来, 需要加强种质资源的保护。  相似文献   

9.
采用线粒体DNA(mt DNA)细胞色素b基因(cytb)和控制区序列,分析长江中游宜都、沙市、燕窝、团风等4个产卵场鳊种群的遗传多样性和遗传结构。结果表明:长江中游鳊群体cytb序列共检出82个多态位点,86种单倍型,平均单倍型多样性指数(Hd)和核苷酸多样性指数(Pi)分别为0.930和0.00244;控制区序列共检出变异位点46个,单倍型76种,Hd指数和Pi指数分别为0.972和0.00505;构建的单倍型网络结构和分子方差分析(AMOVA)显示,4个群体的遗传变异绝大部分来自群体内部,群体间无显著遗传分化;群体间的分化指数(FST)、平均基因流(Nm)和平均K2-P遗传距离均表明,4个鳊地理群体间存在广泛的基因交流,未发生明显群体遗传分化;中性检验表明,鳊历史上发生了群体扩张,扩张时间在第四纪冰期后期。  相似文献   

10.
通过分析我国20个不同地理种群中蜂线粒体COⅡ序列的变异,对中华蜜蜂群体遗传分化程度遗传多样性进行全面研究。结果表明:COⅡ基因部分序列中共发现16个变异位点和18个单倍型,核苷酸差异数的平均值为0.939,核苷酸分歧度(Dxy)在0.1%~0.965%之间变化,核苷酸遗传距离为-0.007%~1.489%。总种群的Fst为0.4978,差异均极显著(P0.001)。研究结果显示种群总体单倍型多样性较为丰富,种群间核苷酸分歧度差异很大。20个东方蜜蜂不同地理种群间存在显著的遗传分化。  相似文献   

11.
研究基于线粒体D-loop区和Cyt b基因部分序列, 分析了广西全州、融水、环江三地禾花鲤(Cyprinus carpio)的遗传结构。在3个群体中共鉴定到19种D-loop与Cyt b序列的组合单倍型, 总的单倍型多样性(Hd)和核苷酸多样性(π)分别为0.916±0.010和0.008±0.004, 禾花鲤线粒体DNA具有单倍型多样性高和核苷酸多样性低的特点。环江群体单倍型多样性最低, 但是核苷酸多样性却最高, 反映了环江群体存在最明显的谱系混杂。分子方差分析(AMOVA)显示遗传变异主要来源于群体内部(71.54%), 禾花鲤三个群体间有显著的遗传分化(Fst=0.285; P<0.01)。系统发育分析表明, 多数样本的线粒体单倍型属于华南鲤(C. carpio rubrefusus)类型, 同时三地禾花鲤中均检测到一定频率的西鲤(C. carpio carpio)或远东鲤(C. carpio haematopterus)类型的线粒体单倍型, 提示禾花鲤可能受到鲤养殖品种的杂交渐渗。研究初步揭示了广西禾花鲤的种质资源现状, 为禾花鲤这一地方特色“稻鱼共作”品种的选育和苗种管理提供了必要的依据。  相似文献   

12.
Polymorphism of the mitochondrial cyt b gene was examined in 35 individuals of common carp and wild common carp (Cyprinus carpio L.). The fish examined represented two natural populations from Khabarovsk krai (Ac and Am), Volga wild common carp, Don wild common carp, and two common carp breeds, Ropsha (strains BB and MM) common carp and Hungarian common carp. The highest level of nucleotide (pi) and haplotype (h) diversity was detected in two strains of Ropsha common carp (MM, pi = 0.67%, h = 0.7; and BB, pi = 0.21%, h = 0.9) and in one population (Am) of Amur wild common carp (pi = 0.26%; h = 0.6). The second population of Amur wild common carp (Ac) and Hungarian common carp were characterized by lower variation estimates (pi = 0.035%, h = 0.4; and pi = 0.09%, h = 0.7, respectively). Genetic homogeneity was demonstrated for the populations of Volga and Don wild common carp (pi = 0, h = 0). In the sample of the cyt b sequences examined, three lineages were identified. Lineages I and II united all haplotypes of the Am Amur wild common carp along with two haplotypes of Ropsha common carp, strain MM. The third lineage (III) was formed by the haplotypes of three individuals of Ropsha common carp strain MM, all representatives of Ropsha common carp strain BB, Hungarian common carp, Ac Amur wild common carp, and Don and Volga wild common carps. Statistically significant amino acid differences were observed only for the sequences, corresponding to haplotypes of lineage III, and the sum of sequences of lineages I and II. Effectiveness of different types of markers to differentiate the two subspecies of European and Amur wild common carp (C. c. carpio and C. c. haematopterus) is discussed, as well as the issues of the origin and dispersal of Russian common carp and wild common carp breeds.  相似文献   

13.
Ten tri- and tetranucleotide microsatellite DNA markers were isolated and characterized from common carp (Cyprinus carpio L.) to estimate genetic potential. These markers were tested in the samples from two closely related carp populations (Cyprinus carpio var. xingguonensis and Cyprinus carpio var. wananensis). The number of the alleles ranged from three to nine, and observed and expected hererozygosities varied from 0.207 to 1.000 and from 0.499 to 0.900 in each population, respectively. No evidence for linkage disequilibrium was found, indicating that these markers will be useful for population studies.  相似文献   

14.
Silver carp Hypophthalmichthys molitrix (Cyprinidae) is native to China and has been introduced to over 80 countries. The extent of genetic diversity in introduced silver carp and the genetic divergence between introduced and native populations remain largely unknown. In this study, 241 silver carp sampled from three major native rivers and two non-native rivers (Mississippi River and Danube River) were analyzed using nucleotide sequences of mitochondrial COI gene and D-loop region. A total of 73 haplotypes were observed, with no haplotype found common to all the five populations and eight haplotypes shared by two to four populations. As compared with introduced populations, all native populations possess both higher haplotype diversity and higher nucleotide diversity, presumably a result of the founder effect. Significant genetic differentiation was revealed between native and introduced populations as well as among five sampled populations, suggesting strong selection pressures might have occurred in introduced populations. Collectively, this study not only provides baseline information for sustainable use of silver carp in their native country (i.e., China), but also offers first-hand genetic data for the control of silver carp in countries (e.g., the United States) where they are considered invasive.  相似文献   

15.
In order to assess genetic diversity and population structure, nine Camellia sinensis var.assamica and three C.taliensis populations from Yunnan, China were evaluated. Based on nucleotide variation of 94 cpDNA RPL32-TRNL sequences, a total of seven distinct haplotypes were detected in the studied populations. It was apparent that C.sinensis var.assamica (h=0.728,π =0.00469) possessed higher levels of genetic diversity than C.taliensis (h =0.610, π =0.00225). However, genetic differentiation among populations of C.sinensis varassamica (Gst=0.580, FST=0.612) was lower than that among C.taliensis populations (Gst=0.696, FST=0.773). Our AMOVA analysis further revealed that the majority of variation was partitioned among populations of the two taxa, while C.sinensis var.assamica (6121%) showed lower level of genetic differentiation than C.taliensis (77.34%). In comparisons to C.taliensis, genetic diversity within C.sinensis var.assamica largely varied among populations, ranging from 0 to 0.809 and from 0 to 0.00487 for haplotype and nucleotide diversity, respectively. Conservation strategies were finally discussed and proposed to efficiently protect ancient tea plantations in China.  相似文献   

16.
Polymorphism of the mitochondrial cyt b gene was examined in 35 individuals of common carp and wild common carp (Cyprinus carpio L.). The fish examined represented two natural populations from Khabarovsk krai (Ac and Am), Volga wild common carp, Don wild common carp, and two common carp breeds, Ropsha (strains BB and MM) common carp and Hungarian common carp. The highest level of nucleotide (π) and haplotype (h) diversity was detected in two strains of Ropsha common carp (MM, π = 0.67%, h = 0.7; and BB, π = 0.21%, h = 0.9) and in one population (Am) of Amur wild common carp (π = 0.26%; h = 0.6). The second population of Amur wild common carp (Ac) and Hungarian common carp were characterized by lower variation estimates (π = 0.035%, h = 0.4; and π = 0.09%, h = 0.7, respectively). Genetic homogeneity was demonstrated for the populations of Volga and Don wild common carp (π = 0, h = 0). In the sample of the cyt b sequences examined, three lineages were identified. Lineages I and II united all haplotypes of the Am Amur wild common carp along with two haplotypes of Ropsha common carp, strain MM. The third lineage (III) was formed by the haplotypes of three individuals of Ropsha common carp strain MM, all representatives of Ropsha common carp strain BB, Hungarian common carp, Ac Amur wild common carp, and Don and Volga wild common carps. Statistically significant amino acid differences were observed only for the sequences, corresponding to haplotypes of lineage III, and the sum of sequences of lineages I and II. Effectiveness of different types of markers to differentiate the two subspecies of European and Amur wild common carp (C. c. carpio and C. c. haematopterus) is discussed, as well as the issues of the origin and dispersal of Russian common carp and wild common carp breeds.  相似文献   

17.
应用微卫星多态分析四个鲤鱼群体的遗传多样性   总被引:28,自引:1,他引:27  
选择12个斑马鱼功能基因的微卫星标记和12个鲤鱼微卫星标记,检测黑龙江鲤(Cyprinus carpiohaematopterusTemminck et Schlegel)、散鳞镜鲤(C.carpio)、荷包红鲤抗寒品系(C.carpiovar.wuyuanensis)、松浦鲤(C.carpioSongpu carp)的群体遗传多样性。共检测到3882个扩增片段,长度为126~489bp,在群体间扩增出1~5个等位基因不等,共计59个等位基因,平均等位基因2.46个。数据经PHYLIP V3.6软件估算和MEGA3软件作图,确立4个群体间的亲缘关系。并应用Bootstrap检验估计系统树中节点的自引导值,并进行了系统发生分析。结果表明①4个群体检测的有效等位基因数都在55个以上,平均观测杂合度为0.36~0.43,平均期望杂合度为0.49~0.53,平均多态信息含量为0.21~0.25,说明这几个群体多态性属于中度偏高水平,遗传多样性较高;②群体间相似系数都在0.84以上,遗传距离较近,为0.067~0.170,与前人研究结果一致。聚类分析显示,松浦鲤与散鳞镜鲤亲缘关系最近,荷包红鲤抗寒品系与它们的亲缘关系较黑龙江鲤更近;③在3个斑马鱼功能基因相关的微卫星位点上,黑龙江鲤缺失特异扩增条带,这可能与几种鱼类的育成史有关。  相似文献   

18.
为探究贵州从江及邻近的榕江、黎平和锦屏以及广西三江、湖南的通道和靖州等地稻田鲤Cyprinus carpio Linnaeus的遗传结构及系统关系, 研究基于mtDNA Cyt b基因测序技术对6个地理群体进行了分析。447尾稻田鲤中共界定出29种Cyt b基因序列单倍型, 结合NCBI中鲤同源序列的系统发育和序列比对分析表明, 从江及邻近苗侗族地区稻田鲤是一个含欧亚2大谱系、3个鲤亚种和多个母系血统成分的混合群体, 主体类群是华南鲤C. carpio rubrofuscus, 同时混有欧洲鲤C. carpio carpio和远东鲤C. carpio haematopterus, 遭受国内外鲤养殖品种的遗传渗析。遗传多样性分析显示, 欧洲鲤亚种群体为低Hd低π, 遗传多样性贫乏, 远东鲤和华南鲤2个亚种群体呈高Hd低π特点。华南鲤6个稻田群体除锦屏为低Hd低π外, 其余都为高Hd低π, 从江的Hd最高, 黎平的π最高。遗传分化和分子方差(AMOVA)分析显示, 谱系间和亚种间存在显著的遗传分化(P<0.001), 锦屏和三江与其他群体存在中等-高度的分化等级, 其余群体间分化较弱, 群体间变异贡献率为16.69%, 群体内为81.14%。综合分析表明, 从江及邻近地区稻田鲤群体间存在有限的遗传交流, 群体内和群体间有不同的遗传结构。研究丰富了该地区稻田鲤遗传背景资料, 可为湘黔桂交界苗侗族地区稻田鲤的种质资源鉴定与保护提供理论依据。  相似文献   

19.
对云南地区栽培的大叶茶(Camellia sinensis var. assamica)9个居群和大理茶(C.taliensis)3个居群的遗传多样性和居群遗传结构进行了比较研究。通过对94条叶绿体DNA RPL32-TRNL序列的核苷酸序列变异进行分析,共发现了7个单倍型。研究结果表明,大叶茶(h=0.728,π=0.00469)比大理茶(h=0.610,π=0.00225)拥有更为丰富的遗传变异,但其居群遗传分化水平(Gst=0.580,FST=0.612)却低于大理茶(Gst=0.696,FST=0.773)。AMOVA分析进一步证实了它们的遗传变异主要存在于居群间,且大叶茶(61.21%)低于大理茶(77.34%)。相对于大理茶,遗传多样性水平在本研究所取的大叶茶居群间存在着较大的差异,单倍型多态性水平变化范围为0~0.809,核苷酸多态性水平变化范围为0~0.00487。最后,讨论并提出了科学有效地保护我国古茶园茶种资源的建议和对策。  相似文献   

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