可可西里自然保护区藏羚羊的微卫星多态性研究

藏羚羊是我国特有的珍稀濒危动物,对其开展遗传多样性的研究具有非常重要的科学价值。为了获取足够的遗传信息并进一步研究藏羚羊在核基因水平上的遗传多样性,对来自可可西里地区的75个藏羚羊干皮张样本进行了微卫星遗传多样性研究。研究从来自牛和绵羊的25个微卫星基因座中筛选到9个具有高度多态性的微卫星基因座(MCM38,MNS64,IOBT395,MCMAI,TGLA68,BM1329,BMS1341,BM3501和MB066)。用非变性聚丙烯凝胶电泳检测微卫星的PCR扩增产物,计算了这9个微卫星基因座的等位基因频率、多态信息含量、基因杂合度等指标并估算了种群数量。结果在75只藏羚羊中共检测到85个等位基因,9个微卫星基因座的等位基因数为7~12个,平均每个基因座检测到9.4个等位基因,有效等位基因数为处于4.676~9.169之间,平均为6.519;基因频率分布在0.007~0.313之间,多态信息含量在0.753~0.881之间,平均为0.818;观察杂合度为0.791~0.897,平均为0.844,期望杂合度为0.786~0.891之间,平均为0.838±0.0132,各基因座观察杂合度与期望杂合度比较接近。固定指数为-0.269~-0.097,平均为-0.163。Shannon’s指数为1.660~2.315,平均为1.990。种群数量的估算结果显示这75个体均来自同一种群。结果表明该种群在核基因水平仍具有丰富的遗传多样性。     

利用微卫星标记研究鸭品种的遗传多样性

利用32个微卫星标记研究了5个福建省地方鸭品种（金定鸭、连城白鸭、莆田黑鸭、山麻鸭和番鸭）和2个对照品种（北京鸭和卡基康贝尔鸭）的遗传多样性和种质特性.结果表明：32个微卫星标记在7个鸭品种中检测到371个等位基因,平均每个基因座有11.719个等位基因,平均多态信息含量为0.522,有效等位基因数在5.141～6961,基因杂合度变化范围在0.512～0.700,杂合度较高;基于Nei氏标准遗传距离(D_S)和D_A遗传距离,采用UPGMA方法构建了系统发生树,将金定鸭、莆田黑鸭、连城白鸭、山麻鸭和卡基康贝尔鸭聚为一类,而北京鸭和番鸭各自聚为一类.所得聚类图与种群的真实关系较为符合.     

黄河下游家绵羊与家山羊遗传关系的微卫星分析

为了探讨家养绵羊与山羊的属间遗传关系,我们利用13个定位于绵羊染色体上的微卫星基因座,分析了黄河下游4个地方绵羊品种、4个地方山羊品种和1个杂交绵羊类群的遗传结构及其系统发生关系.经Hardy-Weinberg平衡检验和中性测试,发现地方绵羊和山羊种群均处于不平衡状态(P＜0.01),61.53%的基因座属于中性位点,说明所研究种群属于非随机交配,可能受到选择、迁移等进化因素的影响.对有效等位基因数、多态信息含量、Shannon信息指数、观察杂合度和期望杂合度等遗传多样性参数进行比较,发现绵羊种群的遗传变异程度明显(P＜0.01或P＜0.05)高于山羊种群,但不同基因座上的差异效应不一致;结合F统计量和亲缘关系等参数,可推测绵羊和山羊虽然均存在不同程度的近交现象(He＞Ho,FIS＞0),但分别属于杂交和近交繁殖.通过群体遗传分化和系统发育拓扑结构分析,证明绵羊属由共同祖先分化而来的时间晚于山羊属,两属间的遗传距离为1.0708-1.5927,遗传分化时间约为19,807-28,955年;绵羊属内品种间的遗传分化程度(FST＜0.05)均低于山羊属内品种间的分化(FST＞0.15).本研究揭示了人工选择对同域家养绵羊与山羊交配系统的形成及群体遗传分化具有深刻的影响.     

我国地方鸡品种保种群微卫星多态性分析与分子标记档案的建立

利用20个微卫星标记对国家家禽品种资源基因库中保存的11个地方鸡品种保种群进行了遗传检测,计算各群体的等位基因频率、平均基因杂合度、平均多态信息含量及各群体间的遗传距离,并用类平均法进行聚类分析。研究结果表明：20个微卫星标记在11个地方鸡品种保种群共检测到176个等位基因,平均为8.8个,基因频率分布在0.013～0.838之间。检测到等位基因中,有45个等位基因为11个地方鸡品种所共有;11个地方鸡品种平均杂合度在0.6800～0.7432之间。其中藏鸡最高,为0.7432;狼山鸡最低,为0.6800;平均多态信息含量在0.6329～0.7023之间,均大于0.5,表现为高度多态性;11 个鸡品种聚为4类。丝羽乌骨鸡、茶花鸡、仙居鸡、藏鸡、萧山鸡聚为一类,鹿苑鸡、狼山鸡聚为一类,固始鸡、北京油鸡、大骨鸡聚为一类,河南斗鸡单独聚为一类;通过利用20个微卫星基因座检测不同世代群体中等位基因及其频率、群体基因平均杂合度和多态信息含量,建立地方鸡品种保种群微卫星标记档案,并分析世代间的差异,预期可以达到监测保种效果的目的。     

中国7个地方绵羊品遗传多样性的微卫星分析

利用26个微卫星标记分析了中国7个地方绵羊（Ovis aries）品种的遗传多样性。通过计算基因频率,平均杂合度（H）、多态信息含量（PIC）及有效等位基因数（Ne）,并根据Nei氏标准遗传距离,利用UPGMA法进行了聚类分析,评估其种内遗传变异和品种间遗传关系。结果表明：26个微卫星位点共检测到278个等位基因,Ne在2.1288-13.3924之间;26个位点均为高度多态位点,PIC在0.6628-0.8712之间,聚类分析表明哈萨克羊、阿勒泰羊和巴音布鲁克羊遗传关系最近;然后与白藏羊,黑藏羊聚为一类,湖羊和晋中羊聚为一类,各绵羊各种的聚类关系与其来源,育成史及地理分布基本一致。     

中国7个地方绵羊品种遗传多样性的微卫星分析

利用26个微卫星标记分析了中国7个地方绵羊（Ovis aries）品种的遗传多样性。通过计算基因频率、平均杂合度（H）、多态信息含量（PIC）及有效等位基因数（N_e）,并根据Nei氏标准遗传距离,利用UPGMA法进行了聚类分析,评估其种内遗传变异和品种间遗传关系。结果表明：26个微卫星位点共检测到278个等位基因,Ne 在2.1288-13.3924之间;以等位基因频率为基础,得出位点的平均杂合度在0.0629-0.5903之间,品种平均杂合度在0.3633-0.4489之间。26个位点均为高度多态位点,PIC在0.6628-0.8712之间。聚类分析表明哈萨克羊、阿勒泰羊和巴音布鲁克羊遗传关系最近;然后与白藏羊、黑藏羊聚为一类;湖羊和晋中羊聚为一类。各绵羊品种的聚类关系与其来源、育成史及地理分布基本一致。     

利用17个微卫星标记分析鳙鱼的遗传多样性

选用本实验室克隆的17个鳙鱼微卫星分子标记分析四川泸州和江西鄱阳湖的两个种群鳙鱼的遗传多样性及种质特性,计算和统计了杂合度、多态信息含量（PIC）、有效等位基因数、等位基因频率、遗传距离、遗传相似系数、Hardy-Weinberg平衡偏离指数等方面内容。结果表明：选择使用17个微卫星标记,其中有4个为单态标记,13个为多态标记。江西和四川鳙鱼群体每个微卫星位点的平均等位基因数分别为3.325及3.882,平均有效等位基因数分别为3.531及2.676,多态位点百分率分别为82.4及70.5, 17个微卫星标记共有等位基因71个,多态微卫星位点的PIC在0.114~0.960之间变动,平均为0.417 ,两群体位点平均观测杂合度为0.385和0.452,平均期望杂合度为0.360和0.422,两个群体间的遗传相似系数为0.897,群体间的遗传距离为0.109。     

采用6个微卫星位点研究6个绵羊品种遗传多样性

利用6个微卫星座位对中国乌珠穆沁羊、小尾寒羊、滩羊、昭通绵羊、呼伦贝尔羊和甘肃高山细毛羊6个绵羊品种,共计280个个体进行遗传多样性分析。计算了6个绵羊品种间的多态信息含量、杂合度和遗传距离,并进行了主成分分析和UPGMA聚类。发现了101个等位基因,平均杂合度0.599-0.691,平均多态信息含量0.609-0.680;甘肃高山细毛羊与其他绵羊品种遗传分歧最大,而呼伦贝尔羊与乌珠穆沁羊间的分歧最小。结果表明6个绵羊品种均具有较高的遗传多样性,品种间的遗传关系与其形成历史、分化及地理分布基本一致。     

长江中上游两个鲢群体遗传变异的微卫星分析

对长江中上游2个鲢群体使用39个微卫星标记进行了遗传多样性分析, 计算并统计了平均观测等位基因数、平均有效等位基因数、多态信息含量、遗传杂合度、Hardy-Weinberg平衡偏离指数、遗传相似系数、遗传距离等遗传参数。结果表明: 万州鲢和监利鲢群体所检测微卫星位点的平均观测等位基因数分别为6.128和4.974; 平均有效等位基因数分别为4.107和3.395; 多态位点百分率分别为100和94.87; 39个微卫星标记共有等位基因259个, 173个等位基因为两群体所共有; 多态微卫星位点的PIC在0.077~0.865之间变动,平均为0.617; 两群体所检测位点平均观测杂合度为0.834和0.775, 平均期望杂合度为0.713和0.623; 两个群体间的遗传相似系数为0.618, 群体间的遗传距离为0.482。结果显示长江中上游两个鲢群体间存在显著遗传分化, 应隶属于不同的种群。     

广西3个品种猪的微卫星遗传多样性分析

本研究利用17个微卫星标记分析广西境内德保猪、隆林猪和石头猪3个品种的群体微卫星遗传多样性及亲缘关系。通过计算它们的微卫星遗传多样性参数,分析3个品种猪的遗传结构变异。结果显示:德保猪、隆林猪和石头猪3个品种的61个个体共检测到了199个等位基因,各位点的等位基因数为8~19个;平均多态信息含量为0.717 5,期望杂合度分别为0.715 2、0.800 9、0.794 2,表明其皆含有丰富的多态信息及较大范围的遗传变异程度;遗传距离分别为0.461 6、0.322 6、0.278 2,遗传相似度系数分别为0.630 3、0.724 3、0.757 2,表明3种猪之间存在着一定的基因交流,为广西地方猪种质资源的合理利用和保护提供理论依据。     

我国主要地方绵羊品种随机扩增多态DNA研究

对蒙古羊、湖羊、滩羊、小尾寒羊、乌珠穆沁羊、藏绵羊、阿勒泰羊7个地方绵羊品种和无角陶赛特羊、德国美利奴羊、萨福克羊3个引入品种基因组DNA进行了RAPD分析。结果表明：（1）RAPD可作为一种有效的标记用于绵羊品种之间遗传亲缘关系的分析。（2）在所使用的43种随机引物中,有35种引物扩增出多态谱带,多态频率为66.24%,说明RAPD技术用于研究绵羊核DNA的遗传变异具有较高的检出率和灵敏度。（3）总群体平均遗传多样性指数（HSP)为0.9139,说明绵羊群体具有较为丰富的遗传多样性。（4）我国地方绵羊品种间的分子聚类关系与其所处的地理位置、考古学结果,以及细胞遗传学研究结果基本,引入品种间的分子聚类关系也与其育成史基本一致。     

新疆8个绵羊品种遗传多样性和系统发生关系的微卫星分析

为分析新疆北疆地区主要绵羊品种的遗传多样性和系统发生关系,利用10个微卫星标记,采用PCR扩增,12％非变性聚丙烯酰胺凝胶电泳、Sanguinetti银染法显色,对新疆北疆地区8个品种、1个杂交一代绵羊群体遗传多样性进行了检测,统计了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,利用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,采用邻结法构建系统发生树;同时根据等位基因频率,利用PHYLIP(3．6)分析软件,采用最大似然法构建系统发生树,应用白举检验估计系统树中结点的白引导值,并进行了系统发生分析。结果表明：10个微卫星位点在9个绵羊群体中的多态信息含量除BMI824、MAF65为低、中度多态外,其余8个微卫星均为高度多态,可作为有效的遗传标记用于各绵羊品种的遗传多样性和系统发生关系的分析;所有绵羊群体的平均PIC(0．5631)、h(0．5721)和E(2．9)均低于国外其他品种的绵羊,其基因多态性和遗传多样性相对贫乏;新疆本地土种阿勒泰羊、哈萨克羊和巴什拜羊与国外引进绵羊品种及混有外血的本地培育品种遗传距离较远,他们聚为不同的两类,各绵羊品种的分子系统发生关系与其来源、育成史、分化及地理分布基本一致。     

Population structure in Indian sheep ascertained using microsatellite information

This study attempts to provide a comprehensive insight into the prevailing genetic status of Indian sheep breeds using microsatellite markers. Seventeen Indian sheep breeds from 3 agroecological zones were analysed using a panel of 25 microsatellite markers. All of the sheep breeds investigated were genetically diverse, as evident from the high allele (>6) and gene (>0.6) diversity values. The gene diversity values for all breeds ranged from 0.621 to 0.780. The within-population heterozygote deficit (F(IS)) varied from -0.098 to 0.234, reflecting significant levels for 12 of the 17 breeds investigated. The average genetic differentiation between all breeds (F(ST)) was 11.1%, revealing moderate discrimination between the indigenous sheep breeds. The genetic distance and principal component analysis revealed a separation of sheep breeds based on geographical propinquity. The Bayesian clustering approach suggested poor breed differentiation in the north-western arid and semi-arid region when compared to the breeds from the eastern and southern peninsular regions. The observed results mirror the divergent management strategies in the different agroecological regions, lack of specific selection policies, and intermixing of breeds in close proximity. Immediate steps to curb the intermixing and erosion of breed purity for some of these breeds need to be implemented, for example, by introducing measures like making proven rams available and ensuring their frequent exchange between flocks. The data generated here provides valuable information about the genetic structure of the 17 Indian sheep breeds and this can be used for designating priorities for their conservation.     

山羊群体遗传多样性的微卫星分析

为了保护和合理利用我国地方山羊品种遗传资源提供理论基础,本研究利用国际农粮组织和国际家畜研究所推荐的10对微卫星引物,结合荧光标记PCR,检测了中国9个地方山羊品种和1个引进山羊品种的遗传多样性。所研究的10个品种中7个呈现出高度多态,3个呈现出中度多态。并共检测到119个等位基因,有效等位基因数在1.4641~9.2911之间,座位平均杂合度在0.2618~0.7672之间,品种平均杂合度在0.5196~0.7024之间,其中SRCRSP23位点和河西绒山羊(HXR)平均杂合度最高。聚类关系(NJ和UPGMA)和主成分分析结果与其起源、育成历史及地理分布基本一致。     

Isolation and Characterization of the Bovine Microsatellite Loci

Microsatellite loci were isolated using five repetitive probes for Korean native cattle. Eleven microsatellite loci were developed based on a biotin hybrid capture method, and enrichment of the genomic libraries (AAAT, TG, AG, T, and TGC repeats) was performed using Sau3AI adapters. The isolated markers were tested in two half-sib Korean cattle families and four imported breeds (Angus, Limousine, Holstein, and Shorthorn). Nine informative microsatellite loci were observed, and two microsatellite loci were revealed as monomorphic in Korean cattle. In the imported breeds, however, all of the markers were informative. In total, 213 alleles were obtained at the 11 loci across five breeds, and the average number of alleles found per locus, considering all populations, was 4.26. Heterozygosity was 0.71 (expected) and 0.57 (observed). The range of the polymorphic information content for the markers in all cattle populations was 0.43-0.69. Eleven percent of genetic variation was attributed to differentiation between populations as determined by the mean F (ST) values. The remaining 89% corresponded to differences among individuals. The isolated markers may be used to identify and classify the local breeds on a molecular basis.     

Microsatellite analysis to estimate genetic relationships among five bulgarian sheep breeds

Herein, genetic relationships among five breeds of Bulgarian sheep were estimated using microsatellite markers. The total number of alleles identified was 226 at the 16 loci examined. D(A) distance values were used for phylogenetic tree construction with the UPGMA algorithm. The two Tsigai and two Maritza populations were found to be geneticallvery closely related to each other y (0.198, and 0.258 respectively). The Pleven Black Head population was distinct from the other four. These results could be useful for preserving genes in these breeds, thereby ensuring their preservation in Bulgaria.     

中国主要地方品种猪血液蛋白遗传多样性研究

实验采用水平板淀粉凝胶电泳技术,对中国地方猪五大类型９个品种,１个引入品种共２０１个个体进行了遗传多样性分析。共分析遗传座痊３０个,其中只有ＭＤＨ、ＰＥＰＢ、Ａ从位具有多在记民生。中国主要地方猪品种的多态座位百分比Ｐ＝０．２００,平均杂２合度Ｈ＝０．０６５,平均等位基因数Ａ＝１．３００。根据基因频率采用ＰＨＹＬＩＰ３．５ｃ民计算Ｎｅｉ氏遗传距离,然后用“ＮＥＩＧＨＢＯＲ”程序分别构建Ｎｅｉｇｈｂｏ     

Genetic diversity of Chinese indigenous sheep breeds inferred from microsatellite markers

To determine the genetic diversity and phylogenetic relationships among Chinese sheep, 10 indigenous breeds and one introduced breed were genotyped for 19 microsatellite loci. The mean number of alleles per breed ranged from 5.44 (Guide Black Fur sheep) to 9.13 (Ujumqin sheep and Hulunbeier sheep), the expected heterozygosity varied from 0.623 (Guide Black Fur sheep) to 0.737 (Zhaotong sheep), and the allelic richness ranged from 5.169 (Guide Black Fur sheep) to 7.610 (Zhaotong sheep). The deviation from Hardy–Weinberg equilibrium (HWE) was statistically significant (P < 0.05) at three loci (SRCRSP5, OarAE129 and DYMS1) in most of the breeds. Chinese sheep breeds had maintained a high level of within-population genetic differentiation (95.23%), with the remainder explained by differentiation among populations (4.77%). The genetic differentiation pattern and genetic relationships among Chinese sheep breeds displayed a high consistency with the traditional classification. Both the Bayesian cluster and principal component analyses showed a reliable clustering pattern, which revealed three major clusters in Chinese indigenous sheep (Mongolian sheep, Kazakh sheep and Tibetan sheep), except Zhaotong and Guide Black Fur sheep. There were probably caused by different breeding history, geography isolation and different levels of inbreeding. This study will help to interpret the genetic characters of Chinese indigenous sheep and benefit to the future conservation programs.     

Genetic diversity and population structure of 10 Chinese indigenous egg-type duck breeds assessed by microsatellite polymorphism

The genetic structure and diversity of 10 Chinese indigenous egg-type duck breeds were investigated using 29 microsatellite markers. The total number of animals examined were 569, on average 57 animals per breed were selected. The microsatellite marker set analysed provided 177 alleles (mean 6.1 alleles per locus, ranging from 3 to 10). All populations showed high levels of heterozygosity with the lowest estimate of 0.539 for the Jinding ducks, and the highest 0.609 observed for Jingjiang partridge ducks. The global heterozygote deficit across all populations (F _IT) amounted to −0.363. About 10% of the total genetic variability originated from differences among breeds, with all loci contributing significantly. An unrooted consensus tree was constructed using the NeighborNet tree based on the Reynold’s genetic distance. The structure software was used to assess genetic clustering of these egg-type duck breeds. Clustering analysis provided an accurate representation of the current genetic relations among the breeds. An integrated analysis was undertaken to obtain information on the population dynamics in Chinese indigenous egg-type duck breeds, and to better determine the conservation priorities.