DNA fingerprints of living fossil Ginkgo biloba by using ISSR and improved RAPD analysis

In this study, we have aimed to genetically characterize Ginkgo biloba. Nine G. biloba samples from different places of China were collected, and DNA was extracted from the leaves of these samples for inter-simple sequence repeat (ISSR) and random amplified polymorphic DNA (RAPD) analysis. ISSR analysis showed high genetic variation among the nine varieties of G. biloba; the polymorphism and similarity coefficients were 87% and 0.40–0.84, respectively. RAPD analysis also showed 93% polymorphism, and the similarity coefficients ranged from 0.44 to 0.87. Persistent genetic isolation that developed for millions of years might influence the genetic variability between the samples of G. biloba. This study generates a genetic map of G. biloba, and reports the highly variable intra-species genetic characteristics of this living fossil among different geographical locations of China. Our study also suggests that ISSR and the improved RAPD markers are useful molecular tools for the genetic characterization of plants.     

Detection of section-specific random amplified polymorphic DNA (RAPD) markers in Lilium

Random amplified polymorphic DNA (RAPD) markers were utilized for the identification of Lilium species and inter-specific hybrids. The optimum annealing temperature of the polymerase chain reaction (PCR) for the RAPD assay in Lilium was 54 °C, which is relatively higher than the temperature used for other genera reported by previous researchers. Among 76 primers used to amplify genomic DNA by PCR, 18 primers (24%) generated polymorphic DNA fragments in Lilium species and hybrids. Cultivars were also identified by RAPD markers. Some amplified fragments were unique to species of each section and to hybrids derived from these species; that is, they were the section-specific DNA markers. Sections, Sinomartagon, Leucolirion b, Leucolirion a and Archelirion could be identified by 6 section-specific markers amplified with five primers. Seven inter-section hybrids showed the section-specific bands of both parental sections, indicating that these markers would be useful for identifying the parental sections of inter-section hybrids.     

Random amplified polymorphic DNA (RAPD) markers in hop, Humulus lupulus: level of genetic variability and segregation in F1 progeny

The level of genetic variation in 24 hop genotypes was studied using the recently developed technique for producing random amplified polymorphic DNAs (RAPDs). Of the 60 primers screened, eight produced polymorphic RAPD bands, 38 produced bands that were monomorphic for all genotypes and 19 did not produce any amplification product. It appeared that the level of polymorphism among the genotypes was generally low. Three of the primers, A11, A17 and C9, were used to determine the stability and segregation of RAPD markers in five families with a total of 182 F₁ progeny. The segregation ratios of these markers in the f₁ progeny suggested that they were inherited in a Mendelian manner. RAPD markers were stable and may be useful for the construction of linkage maps in hop.     

Application of random amplified polymorphic DNA (RAPD) assays in identifying conserved regions of actinomycete genomes

Abstract Various arbitrary primers as well as pUC18/19 'reverse' sequencing primers were used for random amplified polymorphic DNA assays. Use of a modified reverse primer led to amplification of one major approx. 1100-bp band from the chromosomal DNA of all actinomycetes tested; however, the band was not found when DNAs from other bacteria were used in comparable experiments. Hybridization experiments showed that these bands all contained similar genomic regions. Subsequent sequencing of four of these fragments showed they each contained the sequence of the 3' end of the 23S rRNA gene, the intergenic region and the start of the 5S rRNA gene.     

Strain typing of Lentinula edodes by random amplified polymorphic DNA assay

Abstract Single 10-base primers were used to generate randomly amplified polymorphic DNA (RAPD) markers in the shiitake mushroom, Lentinula edodes . Seven primers produced polymorphisms in all 15 strains tested, producing 12–19 bands ranging from 0.34 to 2.52 kb. Thirteen of the 15 strains had unique DNA fingerprints, whereas L. edodes ATCC 28759 and ATCC 28760 exhibited identical RAPD profiles for all the primers. Molecular-genetic markers obtained with the RAPD assay can be used to differentiate strains of L. edodes and have potential applications in mushroom breeding and strain improvement programs.     

利用RAPD对稻蝗属昆虫亲缘关系的研究

通过20个随机引物的PCR扩增,得到了日本主要稻蝗的随机扩增多态性DNA（RAPD）图谱,根据扩增结果,计算了种间相似系数和遗传距离,建立了UPGMA系统树。结果表明,分布没有重叠、种间容易交配、能产生杂种的中华稻蝗台湾亚种与小翅稻蝗的亲缘关系最近;分布重叠的日本稻蝗与中华稻蝗台湾亚种、日本稻蝗和小翅稻蝗的亲缘关系较近。小稻蝗与其它3种稻蝗的亲缘关系较远。     

鲍曼不动杆菌随机扩增多态性DNA法基因分型的研究

目的 利用随机扩增多态性DNA(RAPD)技术对鲍曼不动杆菌进行基因分型建立DNA指纹图谱,调查该菌在各临床科室的流行情况,并将其与药敏谱进行比较.方法 随机收集中南大学湘雅二医院2007年9月到2008年9月分离出的86株鲍曼不动杆菌,采用WHO推荐的K-B法对鲍曼不动杆菌进行药物敏感试验,建立药敏谱,同时利用随机扩增多态性DNA法(RAPD)技术进行基因分型,建立DNA指纹图谱,对二者进行比较,然后结合药敏谱和指纹图谱分析各临床科室鲍曼不动杆菌的感染情况.结果 药物敏感试验将86株鲍曼不动杆菌分为47型,RAPD技术将其分为14型,其中A、F、D、B和L型为5种优势型,其菌株数分别为22、15、11、9和7株.本院ICU,老年病科,神经内科,呼吸内科,神经外科鲍曼不动杆菌检出率较高.结论 RAPD分型方法优于药敏分型,其在流行病学研究上更能证实菌株的相关性,在早期发现和预防感染暴发流行中起重要作用.     

Random amplified polymorphic DNA (RAPD) markers for genetic analysis inAllium

RAPD analysis was applied to onion (Allium cepa) and otherAllium species in order to assess the degree of polymorphism within the genus and to investigate if this approach was suitable for genetic studies of onion. Seven cultivars ofA. cepa, including shallot, and single cultivars of Japanese bunching onion (A. fistulosum), chive (A. schoenoprasum), leek (A. ampeloprasum), and a wild relative of onion (A. roylei), were evaluated for variability using a set of 20 random 10-mer primers. Seven out of the twenty primers revealed scorable polymorphisms between cultivars ofA. cepa and these will be further evaluated for use in genetic mapping. Wide variations in banding profiles between species were observed with nearly every primer tested. These were assessed for use in systematic studies within the genus. Ninety-one band positions were scored (+/-) for all the cultivars studied. Genetic distances between each of the cultivars were calculated and cluster analysis was used to generate a dendrogram showing phylogenetic relationships between them. The resulting analysis was in broad agreement with previous classifications of the species studied, confirming the validity of the method. However, amongst the species studied, it placedA. roylei as the closest relative ofA. cepa, questioning the current classification of the former species in the section Rhizideum.     

三种摇蚊幼虫RAPD扩增条件的优化及在昆虫系统发育分析中的应用

为了研究摇蚊科昆虫种群遗传的多样性,以促进对其资源的合理保护,以萨摩亚摇蚊Chironomus samoensisEdwards基因组DNA为模板,对摇蚊幼虫的RAPD扩增条件进行优化,建立了摇蚊幼虫RAPD扩增反应的最佳体系:按照利用优化的RAPD扩增条件进行研究,实验有着良好的重现性。用16个随机引物对3种摇蚊幼虫类群各10个个体进行RAPD扩增,其中萨摩亚摇蚊共扩增出78个条带,多态座位率为41.03%,Shannon遗传多样性指数为0.2570,群体内相似度为0.8730;红裸须摇蚊Propsilocerus akamusi(Tokunaga)共75个条带,多态座位率为44.0%,Shannon遗传多样性指数为0.2472,群体内相似度为0.8731;刺铗长足摇蚊Tanypus punctipennis(Fabricius)共67个条带,多态座位率为41.79%,Shannon遗传多样性指数为0.1943,群体内相似度为0.9066。聚类分析结果表明,刺铗长足摇蚊与红裸须摇蚊的亲缘关系较近。     

Identification and typing of Malassezia yeasts using amplified fragment length polymorphism (AFLP), random amplified polymorphic DNA (RAPD) and denaturing gradient gel electrophoresis (DGGE)

Three molecular tools, amplified fragment length polymorphism (AFLP), denaturing gradient gel electrophoresis (DGGE) and random amplified polymorphic DNA (RAPD) analysis, were explored for their usefulness to identify isolates of Malassezia yeasts. All seven species could be separated by AFLP and DGGE. Using AFLP, four genotypes could be distinguished within M. furfur. AFLP genotype 4 contained only isolates from deep human sources, and ca. 80% of these isolates were from patients with systemic disease. Most of the systemic isolates belonged to a single RAPD genotype. This suggests that systemic conditions strongly select for a particular genotype. Although the clinical use of DGGE may be limited due to technical demands, it remains a powerful tool for the analysis of complex clinical samples.     

Applications of random amplified polymorphic DNA (RAPD) in molecular ecology

Molecular genetic markers have been developed into powerful tools to analyse genetic relationships and genetic diversity. As an extension to the variety of existing techniques using polymorphic DNA markers, the Random Amplified Polymorphic DNA (RAPD) technique may be used in molecular ecology to determine taxonomic identity, assess kinship relationships, analyse mixed genome samples, and create specific probes. Main advantages of the RAPD technology include (i) suitability for work on anonymous genomes, (ii) applicability to problems where only limited quantities of DNA are available, (iii) efficiency and low expense.     

Genetic variation in agronomically important species of Stylosanthes determined using random amplified polymorphic DNA markers

Summary Random amplified polymorphic DNA (RAPD) markers were generated from 20 cultivars and accessions representing four agronomically important species of Stylosanthes, S. scabra, S. hamata, S. guianensis, and S. humilis. Approximately 200 fragments generated by 22 primers of arbitrary sequence were used to assess the level of DNA variation. Relatively low levels of polymorphism (0–16% of total bands in pairwise comparisons) were found within each species, while polymorphisms between the species were much higher (up to 46%). Very few polymorphisms (0–2%) were detected between the individuals of the same cultivar or accession. A phenogram of relationships among the species was constructed based on band sharing. Four main clusters corresponding to each species were readily distinguished on this phenogram. The allotetraploid species S. hamata and its putative diploid progenitor, S. humilis, were more similar to each other than to S. scabra and S. guianensis. No variation in RAPD markers was found between the two commercial S. hamata cvs Verano and Amiga. Cultivar Oxley in S. guianensis was considerably different from the other cultivars and accessions of this species. The phylogenetic distinctions obtained with RAPDs were in agreement with other studies from morphology, cytology, and enzyme electrophoresis. The low level of polymorphisms observed within each species suggested that interspecific crosses may be a better vehicle for the construction of RAPD linkage maps in Stylosanthes.     

西瓜种质资源遗传亲缘关系的RAPD分析

利用 RAPD 技术对国内外32份西瓜主栽品种与其骨干亲本及野生类型的遗传亲缘关系进行了研究。从720个随机引物(10bp)中筛选出15个能产生稳定多态性的引物用于 RAPD 反应,共扩增出104条 DNA 带,其中多态性 DNA 条带43条,占41.35%,平均每个引物扩增的 DNA 条带的数目为7.0条。聚类分析将供试材料分为6个类群:1个东亚生态型类群、1个美国生态型类群、2个中间生态型类群和2个非洲野生型类群,与传统的西瓜生态型分类基本吻合。每个生态型类群都有其特有的扩增(缺失)条带,同时分析了同一生态型中各个品种之间的亲缘关系及其品种的特异条带。本实验结果不仅从分子水平验证了西瓜是遗传基础狭窄的作物,而且在分子水平对西瓜传统分类与地理生态型分类进行了分析。     

In vitro regeneration of loblolly pine and random amplified polymorphic DNA analyses of regenerated plantlets

 Adventitious buds were induced from organogenic callus derived from mature zygotic embryos of three lines (E-311, E-440, and E-822) of loblolly pine (Pinus taeda L.) within 27 weeks of culture. The influence of cytokinins, silver nitrate, and low-temperature treatment on the differentiation of adventitious buds was analyzed. Elongation of adventitious buds was achieved on TE medium supplemented with 0.5 mg/l indole-3-butyric acid (IBA) and 1 mg/l 6-benzyladenine (BA). After adventitious shoots had rooted on TE medium supplemented with 0.5 mg/l IBA, 2 mg/l BA, and 0.5 mg/l gibberellic acid, 498 regenerated plantlets were transferred to a perlite:peatmoss:vermiculite (1 :>: 1) soil mixture; 351 of these survived in the field. Total DNA was extracted from 21 regenerated plantlets randomly chosen from the 151 regenerated plantlets of line E-822. Random amplified polymorphic DNA (RAPD) analysis using 80 arbitrary oligonucleotide 10-mers showed that 21 primers gave 107 clear reproducible bands, with the amplification products being monomorphic for all of the plantlets of line E-822 tested. A total of 2,247 bands obtained from these studies exhibited no aberration in RAPD banding patterns among the tested plantlets. These results suggest that somatic organogenesis can be used for clonal micropropagation of some lines of loblolly pine without the fear of the appearance of unwanted somaclonal variants. Received: 5 August 2000 / Revision received: 5 September 2000 / Accepted: 10 October 2000     

Genetic relationship of 32 cell lines of the euplotes octocarinatus species complex revealed by random amplified polymorphic DNA (RAPD) fingerprinting

Random amplified polymorphic DNA (RAPD) fingerprinting was used in this study to determine the genetic relationship of different cell lines of the hypotrichous ciliate Euplotes octocarinatus. Stocks isolated from different habitats in the USA, and from a group of genetically recombined laboratory strains, were characterized. Band-sharing indices (D) for all possible pairwise comparisons revealed a remarkable genetic diversity between the different cell lines. Investigation of the genetic structure in natural populations found diversity--although to a different extent--in all populations investigated. No clonal structure could be observed, as proposed for several protozoa and recently shown for E. daidaleos. These findings suggest frequent conjugation in the population of E. octocarinatus. No correlation between the genetic relationship of cell lines from different habitats and the distance between the corresponding sampling locations was found. Once separated geographically, the exchange of genetic material between populations appears to be nearly impossible. Therefore, these groups tend to separate into sibling species. The data generally support the occurrence of different syngens in the E. octocarinatus species complex. This finding is in accordance with our observation that the morphological 'species' of E. octocarinatus consists of several syngens or sibling species, similar to findings for the Paramecium aurelia-, Tetrahymena pyriformis- and E. vannus- species complexes.     

Intra-specific relationships among Tibetan Eared-pheasants based on randomly amplified polymorphic DNA(RAPD) analysis

The Tibetan Eared-pheasant Crossoptilon harmani is a rare species native to China.A captive population has been established in the Beijing Zoo since 1999.In order to determine the kinship of the offsprings in 2001,randomly amplified polymorphic DNA (RAPD) was used to examine the parenthood of seven Tibetan Eared-pheasants in the Beijing Zoo.To amplify the genomic DNA of each individual,53 arbitrary primers were selected.The results of amplifica tions showed that 14 primers had clear and distinct RAPD patterns.Totally,226 amplified fragments were generated by RAPD in this study.Cluster analysis of the seven Tibetan Eared-pheasants indicated that all the four young birds had the same father (No.5 male).This study provides a practical method to determine the relationship of offsprings whose parents are unknown in birds.     

Detection of somaclonal variation in cultured rice cells using digoxigenin-based random amplified polymorphic DNA

A procedure for the non-radioactive detection of random amplified polymorphic DNA (RAPD) was developed and designated as digoxigenin (DIG)-based RAPD. Using this procedure, we analyzed somaclonal variation in cultured cells of rice. Somaclonal variation was found to increase with culture age. More than 50 polymorphic fragments were identified with the four primers tested. Random sequencing of 10 clones generated one intron, one 5′-noncoding, and eight non-redundant expressed sequences. A database search for homology showed that the eight exon sequences displayed a significant similarity to sequences already stored in EMBL, GenBank and DDBJ. The sources of the known genes ranged from microorganism to human, including three rice genes. The results showed that somaclonal variation might have occurred in transfer RNA, ribosomal protein, and other genes during cell culture. Received: 14 November 1997 / Revision received: 21 August 1998 / Accepted: 31 August 1998     

Application of randomly amplified polymorphic DNA (RAPD) analysis for typing avian Salmonella enterica subsp. enterica

Randomly amplified polymorphic DNA (RAPD) analysis was performed for the molecular genetic typing of 30 Salmonella enterica subsp. enterica strains isolated from chickens and ducks in Thailand. Six different primers were tested for their discriminatory ability. While some of the primers could only differentiate between the different serovars, the use of multiple primers showed that the RAPD method could also subdivide within a given serovar. The Ready-To-Go RAPD analysis beads used, resulted in reproducible and stable banding patterns. As the RAPD technique is simple, rapid and rather cheap, we suggest that it may be a valuable new tool for studying the molecular genetic epidemiology of S. enterica ssp. enterica, both inter- and intra-serovars.