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1.
Accurate pedigree information is critical when managing animal breeding programmes and ensure the highest rate of genetic gain. The abundance of available genomic data and the development of high‐throughput genotyping platforms have facilitated the use of single nucleotide polymorphisms (SNPs) as the best DNA markers for genomic selection studies. Furthermore, the superior qualities of SNPs compared with those of microsatellite markers allow standardization between laboratories, which is crucial for developing an international set of markers for use in traceability studies. The objective of this study was to develop a high‐throughput SNP array to assign common carp pedigrees accurately. A 48‐SNP array was developed based on the Fluidigm genotyping platform, and a phylogenetic analysis was performed to distinguish different pedigrees. A likelihood‐based approach was used to infer parental pairs, and the pair with the highest LOD score (log of the ratio of the likelihood given parentage to likelihood given non‐parentage) was assigned. The SNP genotypes of the offspring and candidate parents tested were collected, and 94% of the offspring were assigned to the most‐likely parent pair, which was consistent with the actual pedigree records. Using this SNP assay will allow implementation of offspring testing at large commercial farms where improved accuracy of pedigree assignments and genetic evaluations will increase genetic gains in the common carp aquaculture industry.  相似文献   

2.
Polymorphisms in the growth hormone (GH) gene that is associated with the growth rate of farmed fish have been the target of many breeding programmes. The present study aimed to identify single nucleotide polymorphisms (SNPs) in GH gene regions to evaluate the association of SNP variations with the growth rate of two Nile tilapia: Oreochromis niloticus (Linnaeus, 1758) strains. The targeted regions were amplified, sequenced, aligned and screened for the presence of SNPs; thereafter, performance tests were used to check for the association between SNPs and weight. Allele and genotype frequencies were estimated for each SNP and genotype. Genotype blocks or sets of SNP genotypes and frequencies were also estimated. Association between SNPs and growth rate was statistically evaluated using a univariate linear mixed model that included both fixed and random effects. A total of 10 SNPs were identified, nine in the proximal promoter and one located in the 5′ UTR, forming 10 genotype blocks. In all weight recordings, five genotype blocks were significantly associated with the highest weights. Single nucleotide polymorphisms 6‐10 were also found to be significantly associated with growth (p‐value < .05). Genotypes with higher additive genetic values for weight were identified in the Chitralada strain, suggesting a possible impact of these additive effects of the GH SNP genotype on the growth rate of Nile tilapia. These findings may be used as part of marker‐assisted selection in tilapia breeding programmes.  相似文献   

3.
Custom‐built single‐nucleotide‐polymorphism (SNP) marker systems that are compatible with Sequenom® chemistry are compared with a general purpose microsatellite marker system in their ability to accurately assign Black Tiger shrimp parentage. The microsatellite system consisted of 13 markers, while the SNP systems comprised of 63 (SNPa), 59 (SNPb) or 122 markers (SNPab). Comparisons were made using animals from commercial breeding lines with thresholds for assignment derived using simulated genotypes. Pedigree assignment for commercial lines was highest when panel SNPab was used. Panel SNPa, panel SNPb and Msat functioned with an overall similar level of power for pedigree assignment, however, for some families, the Msat panel was not as powerful. Pedigree assignment for the simulated diploid genotypes was higher for all SNP panels compared with Msat. Overall the three SNP panels provided parentage assignment rates suitable for commercial shrimp breeding programs with assignment rates in the simulated genotypes greater than 96.8% and correct assignments greater than 99.3%. Compared with the microsatellite panel, custom‐built SNP panels, whether they operate as single panels, or as a combined panel, have improved power to perform dam and sire assignment to progeny and provide faster turnaround time as they are compatible with Sequenom® chemistry.  相似文献   

4.
  1. Single nucleotide polymorphism (SNP) markers in anchovy (Engraulis encrasicolus) egg samples were analysed to detect their origin on a small spatial scale (200 km) by assigning genotypes to adult anchovy stocks. The novelty of this work is the application of a rapid high‐throughput method for genotyping each single anchovy egg, in a single execution, using a set of 96 genome‐wide SNPs in a dynamic array system with microfluidic technology (Fluidigm 96.96).
  2. The existence of two ecotypes in E. encrasicolus had already been identified based on SNP polymorphism in the Atlantic Ocean and in the Mediterranean Sea, showing that habitat type (offshore versus coastal/estuarine) is the most important component of genetic differentiation among populations of anchovy.
  3. In this work, anchovy egg genotypes from areas of the Western Mediterranean were assigned to adult populations. Only two localities in which adult anchovies were sampled represented donor populations for the coastal/estuarine egg genotypes. Although some degree of mixing among the hauls could exist, the assignment of egg groups to adult populations led to distinguishing the contributions of distinct ecotypes to new wild generations. We can conclude that the high rate of egg dispersion caused by marine currents and the different degrees of local retention could explain the genetic heterogeneity observed in the adult populations, where eggs from neighbouring spawning sites tend to mix.
  4. The results highlight that this technique represents a new and useful tool for addressing evolutionary questions, breed recognition, assignment, and connectivity assessment of individual eggs, and anchovy population dynamics, for the management of stocks.
  相似文献   

5.
凡纳滨对虾SNP标记开发与家系亲缘关系验证分析   总被引：1，自引：0，他引：1       下载免费PDF全文
本研究基于转录组序列开发了37个SNP标记,并对22个凡纳滨对虾(Litopenaeus vannamei)家系进行了遗传多样性、家系聚类和亲子鉴定分析,探讨SNP标记在对虾家系选择育种中的应用途径。结果显示,37个SNP位点在凡纳滨对虾22个家系中的平均期望杂合度(He)和平均观测杂合度(Ho)分别为0.38和0.34;平均多态信息含量(PIC)为0.30,属于中度多态性(0.25相似文献   

6.
The aim of this study is to screen single nucleotide polymorphisms (SNPs) of the farnesoic acid O‐methyltransferase gene in shrimp, Penaeus chinensis (PcFAMeT), and analyze the potential association between PcFAMeT gene polymorphisms and growth traits in a cultured population. Four SNPs (A163G, G392T, A708G, and T752C) were tested for association with six growth traits in 240 individuals using the polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) method. The association analysis of SNPs of PcFAMeT gene with the six growth traits was carried out using general linear model estimation. Results indicated that SNP2 (G392T) of the PcFAMeT gene was significantly associated with body weight (P < 0.05) and carapace width (P < 0.05). The individuals of genotype GG grew faster than those of genotype GT and TT. The results would provide potential application in future shrimp breeding programs and may be used to improve the efficiency in shrimp, P. chinensis, breeding programs.  相似文献   

7.
Parentage analysis is of vital importance for hatchery production and breeding programmes. Two multiplex PCR protocols including seven tropical spiny lobster (Panulirus homarus) microsatellites (Pho‐G06, Pho‐G25, Pho‐G53, Pho‐G62, Pho‐G74, Pho‐G89 and Pho‐G100) were introduced for parentage assignment. All loci were polymorphic with allele sizes from 113 to 337 base pairs (bp), observed alleles (k) from two to seven and polymorphic information content (PIC) of 0.25 to 0.73. Twenty‐four stage‐3 phyllosoma larvae (39 days posthatching) were collected for paternity exclusion study using selected microsatellites. Exclusion‐based parentage analysis unambiguously assigned 83% of fry (20 of 24) to a single female parent. Of ten putative female parents, five have contributed to the 20 allocated offspring, with one being true parent of 11. Four others were assigned to two or more potential female parents, probably due to genotyping error or the presence of null allele. The exclusion power (EP) for the seven loci varied between 13% and 54% with known genotypes of one parent (P1) and 19% and 71% for given the genotypes of both parents (P2). The theoretical combined parentage exclusion (cEP) power for all seven microsatellites was P1 = 95% and P2 = 99%. The power of discrimination for each locus varied between 0.18 and 0.86. This report presents the first study to utilize microsatellite markers for successful parentage assignment of P. homarus. The selected microsatellites provide a practical tool for parentage analysis in hatchery production of juveniles as well as in future commercial breeding programme of tropical spiny lobsters.  相似文献   

8.
High‐resolution melting (HRM) has been considered as a fast and simple single‐nucleotide polymorphism (SNP) scanning and genotyping method for identifying differences in the shapes of melting curves between different genotypes. Fifty‐six SNPs were developed in the Pacific oyster, Crassostrea gigas by mining expressed sequence tags database, using the HRM method. The frequency of the SNPs was estimated at 1 per 113 bp of contig sequences. Analysis of segregation in a full‐sib family showed that 28 SNPs were polymorphic, with 15 in accordance to expected Mendelian ratios. Linkage grouping of the 28 markers resulted in six linkage groups. The combined power of exclusion of the 42 SNPs, which conformed to Hardy–Weinberg equilibrium, was greater than 99.98%, while the average polymorphic information content was 0.2223. The simulation results showed that the success rate of parentage analysis could be 97% with the 42 SNPs. These SNPs will be useful for pedigree analysis, association studies, and marker‐associated selection of this species .  相似文献   

9.
利用2b-RAD技术对119尾黄条鰤(Seriola lalandi)个体进行测序,共获得黄条鰤SNP分子标记26665个,对黄条鰤个体的体质量和全长这2个重要生长性状进行全基因组关联分析,筛选与体质量和全长性状相关的SNP位点和候选基因。结果显示,黄条鰤体质量性状中共筛选到17个体质量显著关联的SNP位点,找到17个可能的候选基因,全长性状共筛选到12个潜在显著关联位点,找到12个可能的候选基因。利用KEGG数据库对可能的候选基因进行Pathway分析,得知候选基因主要参与了细胞或组织生长发育相关的代谢通路调控过程,可能是影响黄条鰤生长性状密切相关的重要候选SNP位点和功能基因,结果可为今后黄条鰤种质资源可持续利用和育种提供遗传信息资料积累。  相似文献   

10.
随着测序技术的发展,基于单核苷酸多态性(SNP)分子标记的遗传力估计比传统法准确性更高,已被广泛应用于动植物育种中。本研究对不同地理仿刺参(Apostichopusjaponicus)群体的疣足数量进行重测序全基因组水平的SNP遗传力估计,结果显示,次等位基因频率(Minorallele frequency,MAF)>0.05时,在50K SNP基础上均匀抽样,不同SNP密度的仿刺参疣足数量SNP遗传力估计均值范围为(0.566±0.022)~(0.612±0.003);MAF>0.1时,SNP遗传力估计均值范围为(0.586±0.015)~(0.615±0.016),说明50K低密度SNP标记足够捕获数量性状基因座(QTL)大效应和小效应;同时,染色体水平SNP遗传力估计值显示,单个染色体对遗传力的贡献和其长度显著相关,暗示仿刺参疣足数量是一个复杂的数量性状,与该性状相关的基因效应位点散布在各染色体,并由多基因共同作用。本研究结果可为海参低密度SNP芯片的设计开发及海参遗传参数评估提供一定的理论依据。  相似文献   

11.
Pacific bluefin tuna (Thunnus orientalis) has high market value, but its wild populations have decreased in recent years. The broodstock of Pacific bluefin tuna that were hatched artificially and reared under aquaculture conditions is beginning to be used for production. The creation of broodstock with commercially valuable traits, such as rapid growth, is therefore of great interest. Genetic linkage map‐based identification of markers associated with quantitative trait loci (QTLs) facilitates marker‐assisted selection (MAS) breeding and allows efficient genetic improvement of broodstock. Single nucleotide polymorphism (SNP)‐based genetic linkage map construction using the genotyping‐by‐sequencing method can expand the number of mapped markers and help identify growth‐related QTLs. In this study, we constructed sex‐specific maps for 24 linkage groups consisting of 677 SNP and 651 microsatellite markers. The total lengths of 93 progenies in the mapping population followed normal distribution, with an average length of 9.4 mm. We performed composite interval mapping in the mapping population. QTL analysis revealed one significant QTL in LG10 on the female linkage map. The genetic linkage map—the second such map generated for Pacific bluefin tuna—and the growth‐related QTLs detected in this study will be useful for tuna aquaculture MAS programs.  相似文献   

12.
利用2b-RAD技术对119尾黄条[鱼师](Seriola lalandi)个体进行测序,共获得黄条[鱼师]SNP分子标记26665个,对黄条[鱼师]个体的体质量和全长这2个重要生长性状进行全基因组关联分析,筛选与体质量和全长性状相关的SNP位点和候选基因。结果显示,黄条[鱼师]体质量性状中共筛选到17个体质量显著关联的SNP位点,找到17个可能的候选基因,全长性状共筛选到12个潜在显著关联位点,找到12个可能的候选基因。利用KEGG数据库对可能的候选基因进行Pathway分析,得知候选基因主要参与了细胞或组织生长发育相关的代谢通路调控过程,可能是影响黄条[鱼师]生长性状密切相关的重要候选SNP位点和功能基因,结果可为今后黄条[鱼师]种质资源可持续利用和育种提供遗传信息资料积累。  相似文献   

13.
Abstract – We used a targeted gene approach to amplify genomic fragments to characterise single‐nucleotide polymorphisms (SNPs) in introduced European populations of the invasive mosquitofish Gambusia holbrooki. Patterns of diversity within and among European populations of G. holbrooki and American collections of G. holbrooki and Gambusia affinis reveal unexpected high diversities within European populations. This ascertainment bias is one of the major challenges in the development of SNP markers for monitoring species involved in worldwide introductions. Pattern of diversity among European populations confirmed diverse introductions, as suggested by earlier mtDNA studies. However, SNPs showed larger differentiation between populations than had been previously detected with mtDNA sequencing. Five major population groups were identified: central France, southern Iberian, northern Iberian, Eastern Europe and Mediterranean French Rivers.  相似文献   

14.
Estimation of selection response and genealogical tracing in family mixtures require an appropriate tool for parentage analysis. In this study, we tested 19 marker loci for parentage analysis allocation in Mediterranean mussel (Mytilus galloprovincialis). To this aim, we reared families in tanks isolated from wild mussel seed, analysed them using the 19 marker loci and characterized their performances based on Mendelian rules. Probabilities of exclusion of a false parent were estimated for different groups of loci and contrasted to the real paternity assignment. Based on this, we chose nine microsatellites with the highest exclusion probabilities and a real paternity assignment of 99.6%. Next, we analysed 600 individuals reared as in the usual production process, where contamination from wild seed is likely. We obtained a real assignment of 94.7% and were able to identify individuals from the wild as the most likely hypothesis to explain the observed incompatibilities with candidate parents. This information was used to evaluate parental contribution in offspring obtained from gamete mixtures of several parents, which bestowed results of interest for future breeding programs of Mediterranean mussel.  相似文献   

15.
Mediterranean populations of brown trout (Salmo trutta L. complex) have lost a large part of their genetic distinctiveness, mostly due to massive restocking, and the waters of the Gardens of Ninfa (province of Latina, central Italy, Site of Community Importance since 2013) are regarded as one of a few potential reservoirs of autochthonous trout lineages in the Tyrrhenian drainage of the Italian peninsula. In this study, nuclear and mitochondrial markers were used on brown trout samples from Ninfa to estimate non‐Mediterranean influence in the population gene pool, potential changes of genetic structure over time and genetic relationships with other sites known (or suspected) to host native trout gene pools. Striking changes in both microsatellite and mtDNA allele frequencies over a 9‐year time span were found and provided evidence of unrecorded stocking from the nearby Lake Fibreno. Results are analysed in the light of potential ecological consequences of such events on a longer time scale and provide a scientific background for fisheries management and conservation programmes in the area.  相似文献   

16.
The sea cucumber Apostichopus japonicus is one of the most economically important aquaculture species in China, which shows a distinct characteristic of body colour variation. A number of purple variants were obtained in the coast of China, which shows great potential to develop a niche market. In the present study, to understand the genetic basis of green‐purple colour variation, a genome‐wide association study based on the 2b‐RAD sequencing was conducted. As a result, 8,795 genome‐wide single nucleotide polymorphism (SNP) markers were obtained and then applied to the association analysis. Ten most associated SNP loci with p‐value <1.0 × 10–8 were obtained, and they were assigned to 4 chromosomes (chr17, chr21, chr15 and chr05). In genomic regions neighbouring to those SNPs, 33 candidate genes with annotation were obtained and the endothelin‐converting enzyme‐1, which was reported to be involved in pigmentation variation, was identified. To our knowledge, this is the first report of the genetic locus for body colour variation in this species. These findings will be useful for the fine mapping of the determining gene for body colour variation of A. japonicus.  相似文献   

17.
为获得尼罗罗非鱼(Oreochromis niloticus)抗链球菌病相关的单核苷酸多态性(single nucleotide polymorphism,SNP)标记,本研究通过染色体步移法克隆了尼罗罗非鱼Ikaros基因5′调控区序列,长度为4178 bp,并使用生物信息学软件对Ikaros基因的启动子和转录调控元件进行预测和分析。利用PCR产物直接测序法从亲本(P0)尼罗罗非鱼Ikaros基因5′调控区中筛查到5个SNPs,分别为SNP1(g.562,GA)、SNP2(g.217,GT)、SNP3(g.–53,CT)、SNP4(g.–220,TC)和SNP5(g.–579,TC)。利用Snapshot技术对子一代(F1)尼罗罗非鱼易感群体和抗病群体进行相应SNPs的基因分型,分析两个群体遗传多样性参数,结果显示多态信息含量(polymorphism information content,PIC)值在0.0872~0.3747之间,表明Ikaros基因5′调控区中所有SNPs的多态性均较低。Ikaros基因5′调控区SNPs与抗链球菌病性状关联分析结果表明,SNP2、SNP3、SNP4和SNP5的基因型频率和等位基因频率在易感群体和抗病群体中存在显著差异(P0.05)。连锁不平衡分析结果显示Ikaros基因5′调控区SNPs可形成1个单倍块和5种单倍型,其中GGCTT单倍型与抗病性显著相关(P0.05),GGTCT和GTCCC单倍型与易感性显著相关(P0.05)。此外,还发现SNP2和SNP5处于完全连锁状态(r~2=1,LOD=57.25,D′=1),可作为罗非鱼抗链球菌病遗传育种的标签SNP。综上所述,在Ikaros基因5?调控区筛选到4个抗链球菌病相关SNPs和1个单倍型(GGCTT),均可作为尼罗罗非鱼分子育种的候选分子标记。  相似文献   

18.
李军  喻子牛 《南方水产》2010,6(3):74-80
单核苷酸多态性（single nucleotide polymorphisms,SNPs）是基因组水平上单个核苷酸变异所引起的DNA序列多态性,是继限制性片段长度多态性、微卫星标记之后的第三代分子标记。最初SNPs主要应用在人类重要疾病的关联性研究中,随着检测技术不断提高以及各种生物SNP数据库的不断完善,其逐渐被应用于遗传图谱的构建、群体遗传学、亲缘关系、关联分析和基因功能分析等方面。文章主要介绍了SNPs的发生、特点及常用检测方法,综述了SNPs在海洋生物遗传学中的研究进展,以期将SNPs更好地应用到海洋经济动物遗传育种中。  相似文献   

19.
牙鲆家系亲权鉴定的微卫星DNA标记分析   总被引：2，自引：1，他引：2  
刘永新  孙朝徽  王玉芬  刘奕  刘英杰 《水产学报》2015,39(11):1593-1603
为准确进行不同家系的亲权鉴定,筛选具有高亲本排除概率的微卫星DNA标记,从牙鲆选育基础群体中挑选性腺发育良好的雌雄亲本各10尾建立全同胞家系10个,从独立饲养的每个家系中随机选取30尾个体组成系谱结构已知的家系群体,从混合培育的子代群体中随机选取200尾个体组成系谱结构未知的混合群体。48个微卫星DNA标记选自牙鲆第二代遗传连锁图谱,且均匀分布于24个连锁群上,每个连锁群2个标记。家系群体的遗传分析结果发现,10个拥有丰富遗传多态性的微卫星DNA标记表现出高的亲本排除概率,其Excl1和Excl2的范围分别为0.655~0.719和0.792~0.837。随鉴定所用微卫星DNA标记数目的增加,累计排除概率逐步升高。当使用8个微卫星DNA标记鉴定时,累计排除概率达到100%。利用这些标记开展混合群体的亲权鉴定,显示共有13个雌雄个体参与繁殖过程,不同亲本配组产生的后代数量存在差异,亲本与后代群体之间的各项遗传学统计指标不存在明显差异。研究表明,筛选出具有高亲本排除概率的微卫星DNA标记能够有效进行牙鲆家系的亲权鉴定,可以作为今后开展家系选育与DNA分子标记联合育种的候选标记。  相似文献   

20.
  • 1. Genetic analysis is increasingly recognized as a key tool for understanding demography, and is particularly useful for describing patterns of gene flow between putative populations. Most effort has been directed towards vertebrate systems, where any one study often benefits from marker development in related species. The greater diversity of invertebrate taxa presents a challenge, but amplified fragment length polymorphism (AFLP) markers offer a solution, yielding high levels of polymorphism and no prior knowledge of a species' genome.
  • 2. AFLP markers have been used to analyse an unusual metapopulation of an invertebrate, the endangered freshwater mussel, Pseudanodonta complanata, sampled from river systems across the UK. This was done to assess the extent to which individual river systems were genetically isolated from one another.
  • 3. The results show patterns of weak genetic differentiation across the UK, with one hydrologically isolated population in the south west showing clear genetic differentiation from the rest of the country. However, the UK population as a whole exhibits significant isolation by distance, particularly when one population subject to fish stocking is removed, this population probably being seeded with mussel glochidia larvae which use fish as vectors. Genetic estimates of inbreeding reveal a complicated pattern in which inbreeding peaks at intermediate densities. High‐density populations may be genetically diverse due to their size, while the lowest density populations may represent transient groups of emigrants from other, larger populations.
  • 4. The findings show that limited gene flow does exist between some but not all river systems. The isolation of the south‐west population indicates that dispersal is variable and should not be assumed to be present. Waterways that remain hydrologically isolated may require special attention in conservation programmes as they can harbour genetically distinct populations. The balance between river management activities and conservation priorities therefore needs careful consideration. Copyright © 2010 John Wiley & Sons, Ltd.
  相似文献   

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