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61.
Through exploring the microsatellite primers from the random genome sequences of Chinese shrimp (Fenneropenaeus chinensis), some microsatellite primers were obtained with rich polymorphic genetic information, and a triplex PCR was established using three primers (RS1101, RS0683 and H081 primers). By adjusting the final concentration of Mg2 , dNTP and primers, and using a touch-town PCR program, the optimum amplification parameters of PCR system were obtained, which could successfully amplify the three primers in a PCR reaction. In the denatured PAGE gel, the amplified DNA fragments of three primers RS1101, RS0683 and H081 could be easily identified each other. For the triplex PCR system, the PPE (probabilities of paternity exclusion) is 0.967 9, and the DP (discrimination power) is 0.999 327. Using the triplex PCR to test ten individuals of a parentage and their parents, an individual was excluded from the parentage in all of the three microsatellite loci, which might be mixed into the parentage for some unknown reason such as factitious misplay. The triplex PCR will be of great practical value in identifying the parentages of F. chinensis.  相似文献   
62.
微卫星分型方法进行中国明对虾家系系谱鉴定   总被引:2,自引:1,他引:2  
微卫星(microsatellite)又称简单序列重复(simple sequence repeats,SSR),是20世纪80年代末期发展起来的DNA分子标记技术,以其数量多、分布广、多态性丰富、检测快速方便、共显性遗传等优点而被广泛应用于构建连锁图谱、个体识别、亲子鉴定、遗传多样性分析、疾病诊断、基因定位等诸多领域.微卫星研究的层次也从群体、个体到基因的表达.虽然有关微卫星起源、演化等相关的理论问题还未研究清楚,但自微卫星标记被发现始就被应用于相关研究,并显示出明显优势,是最具应用价值的标记技术之一.  相似文献   
63.
荧光标记微卫星分析人工饲养中华绒螯蟹的遗传多样性   总被引:5,自引:1,他引:5  
分析中华绒螯蟹的遗传多样性,采集来自无锡、苏州和上海人工养殖样品102个,运用毛细管电泳检测荧光标记(FAM或HEX)的10个中华绒螯蟹微卫星DNA位点。在所有的3个群体中,单一位点等位基因数从15~42个,平均值为22.9;多态信息含量(PIC)和有效等位基因数(E)分别高达0.826和7.699。结果表明10个位点均为高度多态位点,中华绒螯蟹人工养殖群体具有较高的遗传多样性。欧氏遗传距离、遗传相似性和群体各亚群体内固定系数(Fst)平均值分别为0.439,0.825和0.099,结果显示不同的人工养殖群体之间也存在较大的遗传多样性。除上海群体在同步突变模式(SMM)下,近期不会有瓶颈(P=0.35);所有群体在SMM和无限等位基因模式(IAM)下均有显著或极显著的瓶颈(P〈0.01或0.05),结果说明科学的品种保护计划的迫切性。本研究首次选择遗传标记微卫星DNA评估中华绒螯蟹的遗传多样性,并采用高精度的毛细管电泳检测技术,将对中华绒螯蟹的品种保护和合理利国提倡科学依据。  相似文献   
64.
65.
为对大菱鲆(Scophthalmus maximus)的养殖群体进行微卫星分析研究,作者用70个微卫星位点在大菱鲆亲本后代中的基因型分离方式进行检测与分析。结果显示,70个位点共产生了12种分离方式(♀×♂)。70个微卫星位点中45个位点符合孟德尔遗传定律(P≥0.05),有25个位点偏离了孟德尔遗传定律(P0.05)。平均等位基因数目为2.2,平均有效等位基因数为1.885。平均期望杂合度和观测杂合度分别为0.55和0.537。多态信息含量为0.182~0.699,平均值为0.361。研究证明这些标记大部分可以用于大菱鲆进一步的图谱构建,QTL定位和分子标记辅助育种研究。同时对群体的分析表明,该大菱鲆养殖群体遗传多样性水平较高,可用于进一步的良种繁育。  相似文献   
66.
对海带(Saccharina japonica)转录组测序数据进行分析,从70 497条Unigenes中共检测到9 237个简单序列重复(SSR)位点,并对包含SSR序列的Unigenes进行功能注释。海带转录组中SSR的类型十分丰富,其中单核苷酸和三核苷酸重复SSR的数量最多,分别占SSR总数的40.9%和39.4%,其次为四核苷酸、二核苷酸、五核苷酸和六核苷酸重复,分别占SSR总数的9.8%,6.1%,3.1%和0.7%。SSR重复单元类型共有147种,其重复次数的范围为5~70次。功能注释发现约50%含有SSR的Unigenes获得了注释信息,并且大多数与已知蛋白有同源性。COG、GO功能分类结果均表明,大量含有SSR序列的基因与多种生物功能有关,其中与碳水化合物代谢及参与细胞组成相关的基因数量最多。本研究结果为深入开发功能性SSR标记奠定基础,也为开展海带分子标记辅助选育提供支持。  相似文献   
67.
为了筛选与暗纹东方鲀(Takifugu obscurus)生长相关的分子标记,作者采用SSR结合BSA技术对同龄孵化群体的同池养殖暗纹东方鲀生长差异性状标记进行筛选。利用85对微卫星引物对暗纹东方鲀生长快、慢各30尾个体构建的两个基因池进行分析,共筛选到14个差异位点。然后分析这14个差异微卫星位点在这60个暗纹东方鲀个体中的基因型差异,结果表明:位点TOP03、TOG01、fms15、fms75与生长性状呈现极显著负相关关系(P0.01),fms89与生长性状呈现极显著正相关关系(P0.01)。用另外30个个体(生长快慢各15个)进行验证实验后,结果只有位点fms15、fms75与生长性状显著相关,相关系数分别为–0.411和–0.384。这两个微卫星位点对于暗纹东方鲀生长性状有显著效应,为开展暗纹东方鲀的分子标记辅助育种提供了有价值的参考标记。  相似文献   
68.
Space-based observatories have several advantages over ground-based observatories in searching for asteroids and comets. In particular, the Aten and Interior to Earth’s Orbit (IEO) asteroid classes may be efficiently sought at low solar elongations along the ecliptic plane. A telescope in low Earth orbit has a sufficiently long orbital baseline to determine the parallax for all Aten and IEO class asteroids discovered with this observing strategy. The Near Earth Object Space Surveillance Satellite (NEOSSat) mission will launch a microsatellite to exploit this observing strategy complementing ground-based search programmes.  相似文献   
69.
Unbalanced parental contribution and small effective population size(N e)are common issues during the artifi cial breeding of marine bivalves.The impact of hatchery-spawning practices on parental contribution,effective population size,the N e/N ratio,and genetic diversity are largely unknown.To address this,we conducted a parentage analysis on a complete 3×3 diallel cross of clam M eretrix meretrix using eight microsatellite markers.The genetic diversity of the parents was higher than that of their respective offspring in most crosses(8/9).Sires or dams from the same family contributed unequally to the pool of offspring from a particular cross,and the same parent clam exhibited large variation in parental contribution among different crosses.The variance in male contribution was higher than that of the female contribution in most crosses,suggesting that male contribution was more skewed than for females.The N e/N ratio for nine crosses ranged from 0.58 to 0.86.There was no linear relationship between the sex ratio and the N e/N ratio(P0.05).Moreover,a sex ratio closer to one-to-one does not necessarily mean a larger effective population size.A solution to small effective population size in commercial breeding programs is increasing broodstock numbers and attempting to maintain a balanced sex ratio.  相似文献   
70.
Ovoviviparous black rockfish (Sebastes schlegeli) is an important marine fish species for aquaculture and fisheries in China. Genetic information of this species is scarce because of the lack of microsatellite markers. In this study, a large number of microsatellite markers of black rockfish were isolated by constructing microsatellite-enriched libraries. Female- and male-specific genetic linkage maps were constructed using 435 microsatellite markers genotyped in a full-sib family of the fish species. The female linkage map contained 140 microsatellite markers, in which 23 linkage groups had a total genetic length of 1334.1 cM and average inter-marker space of 13.3 cM. The male linkage map contained 156 microsatellite markers, in which 25 linkage groups had a total genetic length of 1359.6 cM and average inter-marker distance of 12.4 cM. The genome coverage of the female and male linkage maps was 68.6% and 69.3%, respectively. The female-to-male ratio of the recombination rate was approximately 1.07:1 in adjacent microsatellite markers. This paper presents the first genetic linkage map of microsatellites in black rockfish. The collection of polymorphic markers and sex-specific linkage maps of black rockfish could be useful for further investigations on parental assignment, population genetics, quantitative trait loci mapping, and marker-assisted selection in related breeding programs.  相似文献   
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