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1.
Bacteriophage X174 temperature-sensitive and nonsense mutations in eight cistrons were mapped by using two-, three-, and four-factor genetic crosses. The genetic map is circular with a total length of 24 × 10−4wt recombinants per progeny phage. The cistron order is D-E-F-G-H-A-B-C. High negative interference is seen, consistent with a small closed circular deoxyribonucleic acid molecule as a genome.  相似文献   

2.
A Genetic Linkage Map for Cattle   总被引:34,自引:4,他引:34       下载免费PDF全文
We report the most extensive physically anchored linkage map for cattle produced to date. Three-hundred thirteen genetic markers ordered in 30 linkage groups, anchored to 24 autosomal chromosomes (n = 29), the X and Y chromosomes, four unanchored syntenic groups and two unassigned linkage groups spanning 2464 cM of the bovine genome are summarized. The map also assigns 19 type I loci to specific chromosomes and/or syntenic groups and four cosmid clones containing informative microsatellites to chromosomes 13, 25 and 29 anchoring syntenic groups U11, U7 and U8, respectively. This map provides the skeletal framework prerequisite to development of a comprehensive genetic map for cattle and analysis of economic trait loci (ETL).  相似文献   

3.
Genetic Map of Bacteriophage T3   总被引:6,自引:7,他引:6       下载免费PDF全文
About 200 amber mutants of phage T3 were found to lie in 14 different genes. These genes are homologous to known T7 genes. The genetic map of T3 is very similar to that of T7.  相似文献   

4.
Zebrafish Genetic Map with 2000 Microsatellite Markers   总被引:33,自引:0,他引:33  
The zebrafish is the first vertebrate organism used for large-scale genetic screens seeking genes critical to development. These screens have been quite successful, with more than 1800 recessive mutations discovered that speak to morphogenesis of the vertebrate embryo. The cloning of the mutant genes depends on a dense genetic map. The 2000 markers we present here, using microsatellite (CA) repeats, provides 1.2-cM average resolution. One centimorgan in zebrafish is about 0. 74 megabase, so, for many mutations, these markers are close enough to begin positional cloning by YAC walks.  相似文献   

5.
Oligonucleotide primers for 125 simple sequence repeat microsatellite-based genetic markers have been assayed by polymerase chain reaction (PCR) in the CEPH reference family panel. These microsatellites include 101 dinucleotide repeats as well as 24 new tetranucleotide repeats. The average heterozygosity of this marker set was 72.4%. Genetic data were analyzed with the genetic mapping package LINKAGE. A subset of these microsatellite markers define a set of 56 uniquely ordered loci (>1000:1 against local inversion) that span 271 cM. Sixty-seven additional loci were tightly linked to markers on the uniquely ordered map, but could not be ordered with such high precision. These markers were positioned by CMAP into confidence intervals. One hundred thirteen of the microsatellite markers were also tested on a chromosome 3 framework somatic cell hybrid panel that divides this chromosome into 23 cytogenetically defined regions, integrating the genetic and physical maps of this chromosome. The high density, high heterozygosity, and PCR format of this genetically and physically mapped set of markers will accelerate the mapping and positional cloning of new chromosome 3 genes.  相似文献   

6.
The Genetic Map of Escherichia Coli K-12   总被引:48,自引:6,他引:48       下载免费PDF全文
  相似文献   

7.
An Autosomal Genetic Linkage Map of the Sheep Genome   总被引:46,自引:2,他引:46       下载免费PDF全文
We report the first extensive ovine genetic linkage map covering 2070 cM of the sheep genome. The map was generated from the linkage analysis of 246 polymorphic markers, in nine three-generation fullsib pedigrees, which make up the AgResearch International Mapping Flock. We have exploited many markers from cattle so that valuable comparisons between these two ruminant linkage maps can be made. The markers, used in the segregation analyses, comprised 86 anonymous microsatellite markers derived from the sheep genome, 126 anonymous microsatellites from cattle, one from deer, and 33 polymorphic markers of various types associated with known genes. The maximum number of informative meioses within the mapping flock was 222. The average number of informative meioses per marker was 140 (range 18-209). Linkage groups have been assigned to all 26 sheep autosomes.  相似文献   

8.
Based on the results of matings with interrupted conjugation and analysis of marker joint inheritance frequencies, distances between 26 genetic determinants were estimated and a genetic map of Pseudomonas mendocina bacteria was constructed.  相似文献   

9.
A Genetic Linkage Map of the Male Goat Genome   总被引:32,自引:0,他引:32       下载免费PDF全文
This paper presents a first genetic linkage map of the goat genome. Primers derived from the flanking sequences of 612 bovine, ovine and goat microsatellite markers were gathered and tested for amplification with goat DNA under standardized PCR conditions. This screen made it possible to choose a set of 55 polymorphic markers that can be used in the three species and to define a panel of 223 microsatellites suitable for the goat. Twelve half-sib paternal goat families were then used to build a linkage map of the goat genome. The linkage analysis made it possible to construct a meiotic map covering 2300 cM, i.e., >80% of the total estimated length of the goat genome. Moreover, eight cosmids containing microsatellites were mapped by fluorescence in situ hybridization in goat and sheep. Together with 11 microsatellite-containing cosmids previously mapped in cattle (and supposing conservation of the banding pattern between this species and the goat) and data from the sheep map, these results made the orientation of 15 linkage groups possible. Furthermore, 12 coding sequences were mapped either genetically or physically, providing useful data for comparative mapping.  相似文献   

10.
The ease of isolating mutations in zebrafish will contribute to an understanding of a variety of processes common to all vertebrates. To facilitate genetic analysis of such mutations, we have identified DNA polymorphisms closely linked to each of the 25 centromeres of zebrafish, placed centromeres on the linkage map, increased the number of mapped PCR-based markers to 652, and consolidated the number of linkage groups to the number of chromosomes. This work makes possible centromere-linkage analysis, a novel, rapid method to assign mutations to a specific linkage group using half-tetrads.  相似文献   

11.
高通量测序技术和生物信息学的发展极大的促进了山羊分子生物学研究。山羊参考基因组的不断完善以及基因组重测序技术的应用,在全基因组水平上发现了大量的遗传变异信息(SNP、Indel和CNV),丰富了山羊分子群体遗传学研究利用的分子标记。综述了山羊参考基因组组装和全基因组变异图谱的构建及其在山羊上的研究进展,以期为进一步利用分子遗传标记进行山羊的各种性状的遗传基础研究和遗传资源保护利用提供科学依据和参考。  相似文献   

12.
Genetic Linkage Map of the Edible Basidiomycete Pleurotus ostreatus   总被引:3,自引:0,他引:3       下载免费PDF全文
We have constructed a genetic linkage map of the edible basidiomycete Pleurotus ostreatus (var. Florida). The map is based on the segregation of 178 random amplified polymorphic DNA and 23 restriction fragment length polymorphism markers; four hydrophobin, two laccase, and two manganese peroxidase genes; both mating type loci; one isozyme locus (est1); the rRNA gene sequence; and a repetitive DNA sequence in a population of 80 sibling monokaryons. The map identifies 11 linkage groups corresponding to the chromosomes of P. ostreatus, and it has a total length of 1,000.7 centimorgans (cM) with an average of 35.1 kbp/cM. The map shows a high correlation (0.76) between physical and genetic chromosome sizes. The number of crossovers observed per chromosome per individual cell is 0.89. This map covers nearly the whole genome of P. ostreatus.  相似文献   

13.
运用小规模实验初步探讨了以中国人群为基础的遗传图绘制工作的必要性。18个无关汉族3代家系共131份血样采自甘肃省白银地区,常规PCR扩增9号染色体的10个STR基因座,采用非变性聚丙烯酰凝胶电泳分析。PCR产物经克隆测序确定核心序列重复次数,采用标准命名法命名各等位基因,用POPGENE软件包计算各基因座等位基因频率,并进行Hardy-Weiberg平衡检验,用Linkage软件包进行各基因座之间连锁关系分析。根据连锁分析结果绘制了中国人群由10个STR基因座构成的9号染色体遗传图。基于中国人群体的9号染色体10个STR连分析锁分析结果与GDB检索结果之间存在较显著的差异,这种差异同时表现在个别基因座之间和0号染色体遗传图总长度上。男、女遗传结果之间在较显著的差异,这种差异同时表现在个别基因之间和9号染色体总长度上。男、女遗传图总长度为129.21cM和178.4cM,均大高加索入。说明了在运用GDB数据之前,有必要根据实验群体进行基因座的初步评估,并且有必要对基于中国人群体的遗传图进行进一步的研究。  相似文献   

14.
By marker rescue of bacteriophage SP02 sus mutants with purified bacteriophage SP02 DNA fragments, 11 of the 17 known bacteriophage SP02 sus loci were assigned to discrete DNA fragments. The left-most genetic locus, susA, was found to reside near one bacteriophage SP02 terminus (EcoRI-C1 fragment), whereas the right-most genetic locus, susP, was found to reside near the other bacteriophage SP02 terminus (EcoRI-C2 fragment). The physical locations of the intervening genetic loci were found to be consistent with the previously determined genetic order. Evidence was also obtained which suggested that at least one end of a transforming DNA fragment is degraded during DNA uptake by the competent bacterium.  相似文献   

15.
A. Darvasi  A. Weinreb  V. Minke  J. I. Weller    M. Soller 《Genetics》1993,134(3):943-951
A simulation study was carried out on a backcross population in order to determine the effect of marker spacing, gene effect and population size on the power of marker-quantitative trait loci (QTL) linkage experiments and on the standard error of maximum likelihood estimates (MLE) of QTL gene effect and map location. Power of detecting a QTL was virtually the same for a marker spacing of 10 cM as for an infinite number of markers and was only slightly decreased for marker spacing of 20 or even 50 cM. The advantage of using interval mapping as compared to single-marker analysis was slight. ``Resolving power' of a marker-QTL linkage experiment was defined as the 95% confidence interval for the QTL map location that would be obtained when scoring an infinite number of markers. It was found that reducing marker spacing below the resolving power did not add appreciably to narrowing the confidence interval. Thus, the 95% confidence interval with infinite markers sets the useful marker spacing for estimating QTL map location for a given population size and estimated gene effect.  相似文献   

16.
An Integrated Genetic and Cytogenetic Map of the Cucumber Genome   总被引:3,自引:0,他引:3  
The Cucurbitaceae includes important crops such as cucumber, melon, watermelon, squash and pumpkin. However, few genetic and genomic resources are available for plant improvement. Some cucurbit species such as cucumber have a narrow genetic base, which impedes construction of saturated molecular linkage maps. We report herein the development of highly polymorphic simple sequence repeat (SSR) markers originated from whole genome shotgun sequencing and the subsequent construction of a high-density genetic linkage map. This map includes 995 SSRs in seven linkage groups which spans in total 573 cM, and defines ∼680 recombination breakpoints with an average of 0.58 cM between two markers. These linkage groups were then assigned to seven corresponding chromosomes using fluorescent in situ hybridization (FISH). FISH assays also revealed a chromosomal inversion between Cucumis subspecies [C. sativus var. sativus L. and var. hardwickii (R.) Alef], which resulted in marker clustering on the genetic map. A quarter of the mapped markers showed relatively high polymorphism levels among 11 inbred lines of cucumber. Among the 995 markers, 49%, 26% and 22% were conserved in melon, watermelon and pumpkin, respectively. This map will facilitate whole genome sequencing, positional cloning, and molecular breeding in cucumber, and enable the integration of knowledge of gene and trait in cucurbits.  相似文献   

17.
食用菌遗传连锁图谱的构建工作虽然较晚于动植物研究,但随着基础研究不断完善,连锁图谱构建工作陆续开展。文中综述了双孢蘑菇(Agaricus bisporus)、香菇(Lentinula edodes)、双色蜡蘑(Laccaria bicolor)、草菇(Volvariella volvacea)、糙皮侧耳(Pleurotus ostreatus)、杏鲍菇(Pleurotus eryngii)、金针菇(Flammulina velutipes)、斑玉蕈(Hypsizigus marmoreus)等食用菌的遗传连锁图谱研究进展,展望了其应用现状及前景,并对笔者所在的国家食用菌产业技术体系黑木耳育种与菌种繁育团队的黑木耳遗传连锁图谱研究进展进行了简介。  相似文献   

18.
大豆遗传图谱的构建和分析   总被引:45,自引:2,他引:45  
利用大豆栽培品种科丰1号和南农1138-2杂交得到的重组近交系NJRIKY,通过RFLP,SSR,RAPD和AFLP4种分子标记的遗传连锁分析,构建了包含24个连锁群,由792个遗传标记组成的大豆较高密度连锁图谱,该图谱覆盖2320.7cM,平均图距2.9cM,SSR标记的多态性较高,在基因组中的位置相对稳定,可以作为锚定标记,有利于连锁群的归并和不同图谱的比较整合;而AFLP标记对于增加图谱密度效率较高,但其容易出现聚集现象,从而造成连锁群上有很大的空隙(gap),另外,在连锁群中有21.7%的分子标记出现偏分离,该图谱为基因定位,比较基因组学和重要农艺性状的QTL定位等研究打下了基础。  相似文献   

19.
20.
Genetic Map Position of the pdxH Gene in Escherichia coli   总被引:1,自引:0,他引:1       下载免费PDF全文
The gene for pyridoxine phosphate oxidase, pdxH, is located 1.2 min beyond aroD, proximal to trp.  相似文献   

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