WorldWideScience

Sample records for detect induced mutations

  1. Radiation-induced germ-line mutations detected by a direct comparison of parents and children DNA sequences containing SNPs

    International Nuclear Information System (INIS)

    Morimyo, M.; Hongo, E.; Higashi, T.; Wu, J.; Matsumoto, I.; Okamoto, M.; Kawano, A.; Tsuji, S.

    2003-01-01

    Full text: Germ-line mutation is detected in mice but not in humans. To estimate genetic risk of humans, a new approach to extrapolate from animal data to humans or to directly detect radiation-induced mutations in man is expected. We have developed a new method to detect germ-line mutations by directly comparing DNA sequences of parents and children. The nucleotide sequences among mouse strains are almost identical except SNP markers that are detected at 1/1000 frequency. When gamma-irradiated male mice are mated with female mice, heterogeneous nucleotide sequences induced in children DNA are a candidate of mutation, whose assignment can be done by SNP analysis. This system can easily detect all types of mutations such as transition, transversion, frameshift and deletion induced by radiation and can be applied to humans having genetically heterogeneous nucleotide sequences and many SNP markers. C3H male mice of 8 weeks of gestation were irradiated with gamma rays of 3 and 1 Gy and after 3 weeks, they were mated with the same aged C57BL female mice. After 3 weeks breeding, DNA was extracted from parents and children mice. The nucleotide sequences of 150 STS markers containing 300-900 bp and SNPs of parents and children DNA were determined by a direct sequencing; amplification of STS markers by Taq DNA polymerase, purification of PCR products, and DNA sequencing with a dye-terminator method. At each radiation dose, a total amount of 5 Mb DNA sequences were examined to detect radiation-induced mutations. We could find 6 deletions in 3 Gy irradiated mice but not in 1 Gy and control mice. The mutation frequency was about 4.0 x 10 -7 /bp/ Gy or 1.6 x 10 -4 /locus/Gy, and suggested the non-linear increase of mutation rate with dose

  2. Detection of induced male germline mutation: Correlations and comparisons between traditional germline mutation assays, transgenic rodent assays and expanded simple tandem repeat instability assays

    Energy Technology Data Exchange (ETDEWEB)

    Singer, Timothy M. [Mutagenesis Section, Environmental and Occupational Toxicology Division, Safe Environments Programme, 0803A, Health Canada, Ottawa, Ont., K1A 0K9 (Canada); Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, Ont., K1S 5B6 (Canada); Lambert, Iain B. [Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, Ont., K1S 5B6 (Canada); Williams, Andrew [Biostatistics and Epidemiology Division, Safe Environments Programme, 6604B, Health Canada, Ottawa, Ont., K1A 0K9 (Canada); Douglas, George R. [Mutagenesis Section, Environmental and Occupational Toxicology Division, Safe Environments Programme, 0803A, Health Canada, Ottawa, Ont., K1A 0K9 (Canada); Yauk, Carole L. [Mutagenesis Section, Environmental and Occupational Toxicology Division, Safe Environments Programme, 0803A, Health Canada, Ottawa, Ont., K1A 0K9 (Canada)]. E-mail: carole_yauk@hc-sc.gc.ca

    2006-06-25

    Several rodent assays are capable of monitoring germline mutation. These include traditional assays, such as the dominant lethal (DL) assay, the morphological specific locus (SL) test and the heritable translocation (HT) assay, and two assays that have been developed more recently-the expanded simple tandem repeat (ESTR) and transgenic rodent (TGR) mutation assays. In this paper, we have compiled the limited amount of experimental data that are currently available to make conclusions regarding the comparative ability of the more recently developed assays to detect germline mutations induced by chemical and radiological agents. The data suggest that ESTR and TGR assays are generally comparable with SL in detecting germline mutagenicity induced by alkylating agents and radiation, though TGR offered less sensitivity than ESTR in some cases. The DL and HT assays detect clastogenic events and are most susceptible to mutations arising in post-spermatogonial cells, and they may not provide the best comparisons with TGR and ESTR instability. The measurement of induced ESTR instability represents a relatively sensitive method of identifying agents causing germline mutation in rodents, and may also be useful for bio-monitoring exposed individuals in the human population. Any future use of the TGR and ESTR germline mutation assays in a regulatory testing context will entail more robust and extensive characterization of assay performance. This will require substantially more data, including experiments measuring multiple endpoints, a greatly expanded database of chemical agents and a focus on characterizing stage-specific activity of mutagens in these assays, preferably by sampling epididymal sperm exposed at defined pre-meiotic, meiotic and post-meiotic stages of development.

  3. Detection of induced male germline mutation: Correlations and comparisons between traditional germline mutation assays, transgenic rodent assays and expanded simple tandem repeat instability assays

    International Nuclear Information System (INIS)

    Singer, Timothy M.; Lambert, Iain B.; Williams, Andrew; Douglas, George R.; Yauk, Carole L.

    2006-01-01

    Several rodent assays are capable of monitoring germline mutation. These include traditional assays, such as the dominant lethal (DL) assay, the morphological specific locus (SL) test and the heritable translocation (HT) assay, and two assays that have been developed more recently-the expanded simple tandem repeat (ESTR) and transgenic rodent (TGR) mutation assays. In this paper, we have compiled the limited amount of experimental data that are currently available to make conclusions regarding the comparative ability of the more recently developed assays to detect germline mutations induced by chemical and radiological agents. The data suggest that ESTR and TGR assays are generally comparable with SL in detecting germline mutagenicity induced by alkylating agents and radiation, though TGR offered less sensitivity than ESTR in some cases. The DL and HT assays detect clastogenic events and are most susceptible to mutations arising in post-spermatogonial cells, and they may not provide the best comparisons with TGR and ESTR instability. The measurement of induced ESTR instability represents a relatively sensitive method of identifying agents causing germline mutation in rodents, and may also be useful for bio-monitoring exposed individuals in the human population. Any future use of the TGR and ESTR germline mutation assays in a regulatory testing context will entail more robust and extensive characterization of assay performance. This will require substantially more data, including experiments measuring multiple endpoints, a greatly expanded database of chemical agents and a focus on characterizing stage-specific activity of mutagens in these assays, preferably by sampling epididymal sperm exposed at defined pre-meiotic, meiotic and post-meiotic stages of development

  4. Induced mutations in citrus

    International Nuclear Information System (INIS)

    Spiegel-Roy, P.; Vardi, Aliza

    1990-01-01

    Full text: Parthenocarpic tendency is an important prerequisite for successful induction of seedlessness in breeding and especially in mutation breeding. A gene for asynapsis and accompanying seedless fruit has been found by us in inbred progeny of cv. 'Wilking'. Using budwood irradiation by gamma rays, seedless mutants of 'Eureka' and 'Villafranca' lemon (original clone of the latter has 25 seeds) and 'Minneola' tangelo have been obtained. Ovule sterility of the three mutants is nearly complete, with some pollen fertility still remaining. A semi-compact mutant of Shamouti orange has been obtained by irradiation. A programme for inducing seedlessness in easy peeling citrus varieties and selections has been initiated. (author)

  5. Induced skeletal mutations

    International Nuclear Information System (INIS)

    Selby, P.B.

    1979-01-01

    This paper describes a large-scale experiment that, by means of breeding tests, confirmed that many dominant skeletal mutations are induced by large-dose radiation exposure. The author also discusses: (1) the major advantages and disadvantages of the skeletal method in improving estimates of genetic hazard to man; (2) future uses of the skeletal method; (3) direct estimation of risk beyond the first generation using the skeletal method; and (4) the possibility of using the skeletal method as a quick and easy screen for chemical mutagens

  6. Mutations induced in plant breeding

    International Nuclear Information System (INIS)

    Barriga B, P.

    1984-01-01

    The most significant aspects of the use of ionizing radiations in plant breeding are reviewed. Aspects such as basic principles of mutation, expression and selection in obtention of mutants, methods for using induced mutations and sucess achieved with this methodology in plant breeding are reviewed. Results obtained in a program of induced mutation on wheat for high content of protein and lysine at the Universidad Austral de Chile are presented. (Author)

  7. Mutations induced in plant breeding

    Energy Technology Data Exchange (ETDEWEB)

    Barriga B, P. (Universidad Austral de Chile, Valdivia. Inst. de Produccion y Sanidad Vegetal)

    1984-10-01

    The most significant aspects of the use of ionizing radiations in plant breeding are reviewed. Aspects such as basic principles of mutation, expression and selection in obtention of mutants, methods for using induced mutations and sucess achieved with this methodology in plant breeding are reviewed. Results obtained in a program of induced mutation on wheat for high content of protein and lysine at the Universidad Austral de Chile are presented.

  8. Induced mutations in castor

    International Nuclear Information System (INIS)

    Ganesan, K.; Javad Hussain, H.S.; Vindhiyavarman, P.

    2001-01-01

    Castor (Ricinus communis L.) is an important oilseed crop in India. To create variability mutations were induced in two cultivars 'TMV5' (maturing in 130-140 days) and 'CO1' (perennial type). Gamma rays and diethyl sulphate and ethidium bromide were used for seed treatment. Ten doses, from 100 to 1000 Gy were employed. For chemical mutagenesis five concentrations of mutagenes from 10 to 50 mM were tried. No economic mutants could be isolated after treatment with the chemical mutagens. The following economic mutants were identified in the dose 300 Gy of gamma rays. Annual types from perennial CO 1 castor CO 1 is a perennial variety (8-10 years) with bold seeds (100 seed weight 90 g) and high oil content (57%). Twenty-one lines were isolated with annual types (160-180 days) with high yield potential as well as bold seeds and high oil content. These mutants, identified in M 3 generation were bred true in subsequent generations up to M 8 generation. Critical evaluation of the mutants in yield evaluation trials is in progress

  9. Detecting the brachyspina mutation

    DEFF Research Database (Denmark)

    2012-01-01

    This invention relates to methods for the detection of a bovine that is affected by or carrier of brachyspina. It is based on the identification of a 3.3 Kb deletion in the bovine FANCI gene that is shown to cause the brachyspina syndrome. The present invention provides methods and uses for deter...

  10. New mutations affecting induced mutagenesis in yeast.

    Science.gov (United States)

    Lawrence, C W; Krauss, B R; Christensen, R B

    1985-01-01

    Previously isolated mutations in baker's yeast, Saccharomyces cerevisiae, that impair induced mutagenesis were all identified with the aid of tests that either exclusively or predominantly detect base-pair substitutions. To avoid this bias, we have screened 11 366 potentially mutant clones for UV-induced reversion of the frameshift allele, his4-38, and have identified 10 mutants that give much reduced yields of revertants. Complementation and recombination tests show that 6 of these carry mutations at the previously known REV1, REV1 and REV3 loci, while the remaining 4 define 3 new genes, REV4 (2 mutations), REV5 and REV6. The rev4 mutations are readily suppressed in many genetic backgrounds and, like the rev5 mutation, impart only a limited deficiency for induced mutagenesis: it is likely, therefore that the REV4+ and REV5+ gene functions are only remotely concerned with this process. The rev6 mutants have a more general deficiency, however, as well as marked sensitivity to UV and an increased spontaneous mutation rate, properties that suggest the REV6 gene is directly involved in mutation induction. The REV5 gene is located about 1 cM proximal to CYC1 on chromosome X.

  11. Mutations induced by ultraviolet light

    International Nuclear Information System (INIS)

    Pfeifer, Gerd P.; You, Young-Hyun; Besaratinia, Ahmad

    2005-01-01

    The different ultraviolet (UV) wavelength components, UVA (320-400 nm), UVB (280-320 nm), and UVC (200-280 nm), have distinct mutagenic properties. A hallmark of UVC and UVB mutagenesis is the high frequency of transition mutations at dipyrimidine sequences containing cytosine. In human skin cancers, about 35% of all mutations in the p53 gene are transitions at dipyrimidines within the sequence 5'-TCG and 5'-CCG, and these are localized at several mutational hotspots. Since 5'-CG sequences are methylated along the p53 coding sequence in human cells, these mutations may be derived from sunlight-induced pyrimidine dimers forming at sequences that contain 5-methylcytosine. Cyclobutane pyrimidine dimers (CPDs) form preferentially at dipyrimidines containing 5-methylcytosine when cells are irradiated with UVB or sunlight. In order to define the contribution of 5-methylcytosine to sunlight-induced mutations, the lacI and cII transgenes in mouse fibroblasts were used as mutational targets. After 254 nm UVC irradiation, only 6-9% of the base substitutions were at dipyrimidines containing 5-methylcytosine. However, 24-32% of the solar light-induced mutations were at dipyrimidines that contain 5-methylcytosine and most of these mutations were transitions. Thus, CPDs forming preferentially at dipyrimidines with 5-methylcytosine are responsible for a considerable fraction of the mutations induced by sunlight in mammalian cells. Using mouse cell lines harboring photoproduct-specific photolyases and mutational reporter genes, we showed that CPDs (rather than 6-4 photoproducts or other lesions) are responsible for the great majority of UVB-induced mutations. An important component of UVB mutagenesis is the deamination of cytosine and 5-methylcytosine within CPDs. The mutational specificity of long-wave UVA (340-400 nm) is distinct from that of the shorter wavelength UV and is characterized mainly by G to T transversions presumably arising through mechanisms involving oxidized DNA

  12. Development of techniques using DNA analysis method for detection/analysis of radiation-induced mutation. Development of an useful probe/primer and improvement of detection efficacy

    International Nuclear Information System (INIS)

    Maekawa, Hideaki; Tsuchida, Kozo; Hashido, Kazuo; Takada, Naoko; Kameoka, Yosuke; Hirata, Makoto

    1999-01-01

    Previously, it was demonstrated that detection of centromere became easy and reliable through fluorescent staining by FISH method using a probe of the sequence preserved in α-satelite DNA. Since it was, however, found inappropriate to detect dicentrics based on the relative amount of DNA probe on each chromosome. A prove which allows homogeneous detection of α-satelite DNA for each chromosome was constructed. A presumed sequence specific to kinetochore, CENP-B box was amplified by PCR method and the product DNA was used as a probe. However, the variation in amounts of probe DNA among chromosomes was decreased by only about 20%. Then, a program for image processing of the results obtained from FISH using α-satelite DNA was constructed to use as a marker for centromere. When compared with detection of abnormal chromosomes stained by the conventional method, calculation efficacy for only detection of centromere was improved by the use of this program. Calculation to discriminate the normal or not was still complicated and the detection efficacy was little improved. Chromosomal abnormalities in lymphocytes were used to detect the effects of radiation. In this method, it is needed to shift the phase of cells into metaphase. The mutation induced by radiation might be often repaired during shifting. To exclude this possibility, DNA extraction was conducted at a low temperature and immediately after exposure to 137 Cs, and a rapid genome detection method was established using the genome DNA. As the model genomes, the following three were used: 1) long chain repeated sequences widely dispersed over chromosome, 2) cluster genes, 3) single copy genes. The effects of radiation were detectable at 1-2 Gy for the long repeated sequences and at 7 Gy for the cluster genes, respectively, whereas no significant effects were observed at any Gy tested for the single copy genes. Amplification was marked in the cells exposed at 1-10 Gy (peak at 4 Gy), suggesting that these regions had

  13. Induced mutations in sesame breeding

    International Nuclear Information System (INIS)

    Ashri, A.

    2001-01-01

    The scope of induced mutations in sesame (Sesamum indicum L.) breeding is reviewed. So far in Egypt, India, Iraq, Rep. of Korea, and Sri Lanka, 14 officially released varieties have been developed through induced mutations: 12 directly and 2 through cross breeding (one using the 'dt45' induced mutant from Israel). For another variety released in China there are no details. The induced mutations approach was adopted primarily in order to obtain genetic variability that was not available in the germplasm collection. The mutagens commonly applied have been gamma rays, EMS and sodium azide. Sesame seeds can withstand high mutagen doses, and there are genotypic differences in sensitivity between varieties. The mutants induced in the above named countries and others include better yield, improved seed retention, determinate habit, modified plant architecture and size, more uniform and shorter maturation period, earliness, resistance to diseases, genic male sterility, seed coat color, higher oil content and modified fatty acids composition. Some of the induced mutants have already given rise to improved varieties, the breeding value of other mutants is now being assessed and still others can serve as useful markers in genetic studies and breeding programmes. (author)

  14. Induced mutation of Dendrobium orchid

    International Nuclear Information System (INIS)

    Sakinah Ariffin; Mohd Nazir Basiran

    2000-01-01

    Dendrobiiim orchids serve as the main orchid cut flower export of Malaysia. The wide range of colour and forms presently available in the market are obtained through hybridisation. Induced mutation breeding program was initiated on a commercial variety Dendrobium 'Sonia Kai' to explore the possibilities of obtaining new colour and forms. Matured seeds from self pollination were cultured and irradiated at 35 Gy at the protocorm-like bodies (PLBS) stage. Selection of induced mutations was done after the first flowering of the plants regenerated from the irradiated protocorms. Results showed changes in flower colour, shape and size. Most of these chances are expressed in different combinations in the petals, sepals and lip of the flowers. Thus, resulting. in a very wide spectrum of mutations. Some of these chances are not stable. To date, mutants that showed stable characteristics changes are grouped into 11 categories based on flower colour and form. These results show that the combination of its vitro technique and induced mutation can be applied in orchid breeding to produce new interesting and attractive variety for the market

  15. Induced Mutations in Thai Rice

    International Nuclear Information System (INIS)

    Klakhaeng, Kanchana

    2014-01-01

    Rice is the primary source of food for more than half of the world's population. It benefits greatly from technological inputs in the area of breeding such as induced mutation. Induced mutation can produce mutants with significant improvement in plant type, maturity, yields and protein ratio when compared to the parent. These improved traits enable the mutants to fit into farming systems with either shorter or longer growing seasons. Three induced mutant rice varieties, including RD6, RD10 and RD15, are well accepted by farmers and consumers in Thailand. RD6 and RD15 were aromatic, photosensitive varieties which were derived from KDML105 by acute irradiation of 20 and 15 kilorad gamma ray, respectively. After induced mutation, pedigree selection was applied. RD6 showed drought tolerance and also good grain quality including softness and good aroma with a higher average yield than the famous glutinous variety, San-Pah-Tong. Additionally, it was resistant to blast and brown spot diseases with an average yield of 4.19 tons/ha. RD15 showed drought tolerance and resistance to brown spot disease with the highest yield of 3.5 tons/ha. These two mutant varieties are currently the most famous aromatic rice varieties in Thailand. On the other hand, RD10 is a glutinous, photoperiod insensitive rice variety which was derived from RD1 by irradiation of 1 kilorad fast neutrons. RD10 showed good grain quality such as softness and stickiness with the yield of 4.25 tons/ha. As an on-going project, recommended rice varieties were irradiated with electron beam for anaerobic germination ability, submergence tolerance, stagnant-flood tolerance and also internode elongation.

  16. Gamma ray induced somatic mutations in rose

    International Nuclear Information System (INIS)

    Datta, S.K.

    1989-01-01

    Budwood of 32 rose cultivars (Rosa spp.) was exposed to 3-4 krad of gamma rays and eyes were grafted on Rosa indica var. odorata root stock. Radiosensitivity with respect to sprouting, survival and plant height, and mutation frequency varied with the cultivar and dose of gamma rays. Somatic mutations in flower colour/shape were detected as chimera in 21 cultivars. The size of the mutant sector varied from a narrow streak on a petal to a whole flower and from a portion of a branch to an entire branch. 14 mutants were detected in M 1 V 1 , four in M 1 V 2 and three in M 1 V 3 . Maximum number of mutations was detected following 3 krad treatment. Eyes from mutant branches were grafted again on root stock and non-chimeric mutants were aimed at by vegetative propagation. Mutants from 11 cultivars only could be isolated in pure form. Isolation of non-chimeric mutants sometimes is difficult due to weak growth of a mutant branch. In such a case, all normal looking branches are removed to force a better growth of the mutant branch. It is advisable to maintain irradiated plants at least for four years with drastic pruning in each year. Nine mutants viz. 'Sharada', 'Sukumari', 'Tangerine Contempo', 'Yellow Contempo', 'Pink Contempo', 'Striped Contempo', 'Twinkle', 'Curio' and 'Light Pink Prize' have already been released as new cultivars for commercialization [ref. MBNL No. 23 and 31] and others are being multiplied and assessed. The mutation spectrum appears to be wider for the cultivars 'Contempo' and 'Imperator'. Pigment composition of the original variety is relevant for the kind of flower colour mutations that can be induced

  17. Rice breeding with induced mutations

    Energy Technology Data Exchange (ETDEWEB)

    1968-06-01

    The Joint FAO/IAEA Division of Atomic Energy in Food and Agriculture decided in 1964 to organize a co-ordinated research programme on the use of induced mutations in rice breeding. The programme was organized within the framework of activities of the International Rice Commission. This is a report of the Third Co-ordination Meeting of the participants, which was held in Taipei, 5-9 June 1967. As the projects, which together make up the co-ordinated programme, are at different stages of progress, the report contains a variety of papers including completed studies, field and progress reports, and highlights of the discussions with some additional recommendations prepared by the participants. Refs, figs and tabs.

  18. Molecular methods for the detection of mutations.

    Science.gov (United States)

    Monteiro, C; Marcelino, L A; Conde, A R; Saraiva, C; Giphart-Gassler, M; De Nooij-van Dalen, A G; Van Buuren-van Seggelen, V; Van der Keur, M; May, C A; Cole, J; Lehmann, A R; Steinsgrimsdottir, H; Beare, D; Capulas, E; Armour, J A

    2000-01-01

    We report the results of a collaborative study aimed at developing reliable, direct assays for mutation in human cells. The project used common lymphoblastoid cell lines, both with and without mutagen treatment, as a shared resource to validate the development of new molecular methods for the detection of low-level mutations in the presence of a large excess of normal alleles. As the "gold standard, " hprt mutation frequencies were also measured on the same samples. The methods under development included i) the restriction site mutation (RSM) assay, in which mutations lead to the destruction of a restriction site; ii) minisatellite length-change mutation, in which mutations lead to alleles containing new numbers of tandem repeat units; iii) loss of heterozygosity for HLA epitopes, in which antibodies can be used to direct selection for mutant cells; iv) multiple fluorescence-based long linker arm nucleotides assay (mf-LLA) technology, for the detection of substitutional mutations; v) detection of alterations in the TP53 locus using a (CA) array as the target for the screening; and vi) PCR analysis of lymphocytes for the presence of the BCL2 t(14:18) translocation. The relative merits of these molecular methods are discussed, and a comparison made with more "traditional" methods.

  19. Radiation-induced mutation at minisatellite loci

    International Nuclear Information System (INIS)

    Dubrova, Y.E.; Nesterov, V.N.; Krouchinsky, N.G.

    1997-01-01

    We are studying the radiation-induced increase of mutation rate in minisatellite loci in mice and humans. Minisatellite mutations were scored by multilocus DNA fingerprint analysis in the progeny of γ-irradiated and non-irradiated mice. The frequency of mutation in offspring of irradiated males was 1.7 higher that in the control group. Germline mutation at human minisatellite loci was studied among children born in heavily polluted areas of the Mogilev district of Belarus after the Chernobyl accident and in a control population. The frequency of mutation assayed both by DNA fingerprinting and by eight single locus probes was found to be two times higher in the exposed families than in the control group. Furthermore, mutation rate was correlated with the parental radiation dose for chronic exposure 137 Cs, consistent with radiation-induction of germline mutation. The potential use of minisatellites in monitoring germline mutation in humans will be discussed

  20. Radiation induced chlorophyll mutations in rice

    International Nuclear Information System (INIS)

    Bari, G.; Mustafa, G.; Soomro, A.M.; Baloch, A.W.

    1985-01-01

    Air dried grains of four local varieties of rice were treated with gamma-rays and fast neutrons for determining their mutagenic effectiveness through the occurence of chlorophyll mutations. Fast neutrons were more effective in inducing chlorophyll mutations and the rice variety Basmati 370 produced maximum number of mutations followed by varieties Sonahri Sugdasi, Jajai 77 and Sada Gulab. The highest frequency of chlorophyll mutations was that of albina types followed by striata types. The xantha, viridis and tigrina types of mutations were less frequent. (authors)

  1. High resolution melting analysis for the detection of EMS induced mutations in wheat SbeIIa genes

    Directory of Open Access Journals (Sweden)

    Botticella Ermelinda

    2011-11-01

    Full Text Available Abstract Background Manipulation of the amylose-amylopectin ratio in cereal starch has been identified as a major target for the production of starches with novel functional properties. In wheat, silencing of starch branching enzyme genes by a transgenic approach reportedly caused an increase of amylose content up to 70% of total starch, exhibiting novel and interesting nutritional characteristics. In this work, the functionality of starch branching enzyme IIa (SBEIIa has been targeted in bread wheat by TILLING. An EMS-mutagenised wheat population has been screened using High Resolution Melting of PCR products to identify functional SNPs in the three homoeologous genes encoding the target enzyme in the hexaploid genome. Results This analysis resulted in the identification of 56, 14 and 53 new allelic variants respectively for SBEIIa-A, SBEIIa-B and SBEIIa-D. The effects of the mutations on protein structure and functionality were evaluated by a bioinformatic approach. Two putative null alleles containing non-sense or splice site mutations were identified for each of the three homoeologous SBEIIa genes; qRT-PCR analysis showed a significant decrease of their gene expression and resulted in increased amylose content. Pyramiding of different single null homoeologous allowed to isolate double null mutants showing an increase of amylose content up to 21% compared to the control. Conclusion TILLING has successfully been used to generate novel alleles for SBEIIa genes known to control amylose content in wheat. Single and double null SBEIIa genotypes have been found to show a significant increase in amylose content.

  2. Molecular mechanisms of induced-mutations

    International Nuclear Information System (INIS)

    Kato, Takeshi

    1985-01-01

    The outcome of recent studies on mechanisms of induced-mutations is outlined with particular emphasis on the dependence of recA gene function in Escherichia coli. Genes involved in spontaneous mutation and x-ray- and chemical-induced mutation and genes involved in adaptive response are presented. As for SOS mutagenesis, SOS-induced regulation mechanisms and mutagenic routes are described. Furthermore, specificity of mutagens themselves are discussed in relation to mechanisms of base substitution, frameshift, and deletion mutagenesis. (Namekawa, K.)

  3. Induced mutations - a tool in plant research

    International Nuclear Information System (INIS)

    1981-01-01

    These proceedings include 34 papers and 18 brief descriptions of poster presentations in the following areas as they are affected by induced mutations: advancement of genetics, plant evolution, plant physiology, plant parasites, plant symbioses, in vitro culture, gene ecology and plant breeding. Only a relatively small number of papers are of direct nuclear interest essentially in view of the mutations being induced by ionizing radiations. The papers of nuclear interest have been entered as separate and individual items of input

  4. ENU-induced phenovariance in mice: inferences from 587 mutations

    Directory of Open Access Journals (Sweden)

    Arnold Carrie N

    2012-10-01

    Full Text Available Abstract Background We present a compendium of N-ethyl-N-nitrosourea (ENU-induced mouse mutations, identified in our laboratory over a period of 10 years either on the basis of phenotype or whole genome and/or whole exome sequencing, and archived in the Mutagenetix database. Our purpose is threefold: 1 to formally describe many point mutations, including those that were not previously disclosed in peer-reviewed publications; 2 to assess the characteristics of these mutations; and 3 to estimate the likelihood that a missense mutation induced by ENU will create a detectable phenotype. Findings In the context of an ENU mutagenesis program for C57BL/6J mice, a total of 185 phenotypes were tracked to mutations in 129 genes. In addition, 402 incidental mutations were identified and predicted to affect 390 genes. As previously reported, ENU shows strand asymmetry in its induction of mutations, particularly favoring T to A rather than A to T in the sense strand of coding regions and splice junctions. Some amino acid substitutions are far more likely to be damaging than others, and some are far more likely to be observed. Indeed, from among a total of 494 non-synonymous coding mutations, ENU was observed to create only 114 of the 182 possible amino acid substitutions that single base changes can achieve. Based on differences in overt null allele frequencies observed in phenotypic vs. non-phenotypic mutation sets, we infer that ENU-induced missense mutations create detectable phenotype only about 1 in 4.7 times. While the remaining mutations may not be functionally neutral, they are, on average, beneath the limits of detection of the phenotypic assays we applied. Conclusions Collectively, these mutations add to our understanding of the chemical specificity of ENU, the types of amino acid substitutions it creates, and its efficiency in causing phenovariance. Our data support the validity of computational algorithms for the prediction of damage caused by

  5. Effects of spermine on the detection of induced forward mutation at the CAN1 locus in yeast: evidence for selection against canavanine-resistant mutants

    Energy Technology Data Exchange (ETDEWEB)

    McDougall, K.J.; Lemontt, J.F.

    1979-01-01

    The effect of exogenous spermine tetrahydrochloride (0.5 mg/ml) on hydrazine- and nitrous acid-induced forward mutation to canavanine resistance (CAN1 ..-->.. can1, normal to defective arginine permease) was examined in stationary-phase haploid Saccharomyces cerevisiae. Post-treatment cell division (specifically DNA replication) is required for hydrazine mutagenesis at this locus, whereas nitrous acid mutagenesis exhibits, in addition, a significant post-treatment-independent component.

  6. Induced mutations for crop improvement

    International Nuclear Information System (INIS)

    Micke, A.; Donini, B.; Maluszynski, M.

    1990-01-01

    Mutation induction has become an established tool in plant breeding to supplement existing germ plasma and to improve cultivars in certain specific traits. Hundreds of improved varieties have been released to farmers for many different crop species, demonstrating the economic value of the technology. Limitations arise mainly from the large mutagenized populations to be screened and from the unsatisfactory selection methods. Both limitations may be eased to some extent by advances in techniques of plant in-vitro culture. (author). Refs, 1 fig., 7 tabs

  7. Radiation-induced mutations in mammals

    International Nuclear Information System (INIS)

    Ehling, U.H.

    1993-01-01

    The aims of the proposed project are to provide a better basis for extrapolation of animal data to man. Genetic endpoint, strain and species comparisons are made, which will provide critical experimental data regarding strategies in extrapolating laboratory animal data to man. Experiments were conducted to systematically compare the spontaneous and radiation-induced mutation rates for recessive specific-locus, dominant cataract and enzyme activity alleles in the mouse as well as a comparison of the mutation rate in the mouse and hamster for dominant cataract and enzyme activity alleles. The comparison of the radiation-dose response for recessive specific-locus and dominant cataract mutations are extended. Selected mutations are characterized at the genetic, biochemical and molecular levels. (R.P.) 5 refs., 3 tabs

  8. Radiation-induced mutations and plant breeding

    International Nuclear Information System (INIS)

    Naqvi, S.H.M.

    1985-01-01

    Ionizing radiation could cause genetic changes in an organism and could modify gene linkages. The induction of mutation through radiation is random and the probability of getting the desired genetic change is low but can be increased by manipulating different parameters such as dose rate, physical conditions under which the material has been irradiated, etc. Induced mutations have been used as a supplement to conventional plant breeding, particularly for creating genetic variability for specific characters such as improved plant structure, pest and disease resistance, and desired changes in maturity period; more than 200 varieties of crop plants have been developed by this technique. The Pakistan Atomic Energy Commission has used this technique fruitfully to evolve better germplasm in cotton, rice, chickpea, wheat and mungbean; some of the mutants have become popular commercial varieties. This paper describes some uses of radiation induced mutations and the results achieved in Pakistan so far

  9. Radiation-induced dominant skeletal mutations in mice

    International Nuclear Information System (INIS)

    Selby, P.B.

    1979-01-01

    Skeletons were chosen for the attempt to determine the overall damage by radiation to one body system largely bacause they can be prepared readily for detailed study. Dominant mutations were of special interest because they are the type of mutations that would account for almost all damage induced in the early generations. The male offsprings derived from spermatogonial irradiation were used in the mutation-rate experiment, and the mutation frequency of 1.4% per gamete was found. The general dominant skeletal mutations are 1) the fusions of bones or other changes in individual bones, 2) the gross changes in bone shapes, usually caused by incomplete or too extensive bone growth, or 3) the shifts in the relative positions of bones. The recessive lethality in the period between implantation and birth can be recognized by the expected high death rate of implants in approximately 1/4 of the crosses that are between heterozygotes for a given mutation. The recessive lethal mutations may account for an important fraction of human genetic disorders owing to their dominant deleterious effects which represent only a small fraction, but because of their easy detection, they have been studied more than other dominants. At least 45, or 27%, of 164 dominant visibles in mice, ignoring those concerned with enzyme polymorphisms and immunological traits, appear to be recessive lethals. (Yamashita, S.)

  10. Radiation induced mutations for plant selection

    International Nuclear Information System (INIS)

    Brunner, H.

    1994-01-01

    The successful use of plant breeding for improving crops requires the existence of genetic variation of useful traits. Unfortunately, the desired variation is often lacking. However, radiation can be used to induce mutations and thereby generate genetic variation from which desired mutants may be selected. Mutation induction has become a proven way of creating variation within a crop variety. It offers the possibility of inducing desired attributes that either cannot be expressed in nature or have been lost during evolution. More than 1700 mutant cultivars of crop plants with significantly improved attributes such as increased yield, improved quality, disease and stress resistance, have been released worldwide in the last thirty years. The Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture has contributed to these achievements through the promotion of research and development in mutation breeding techniques using nuclear and related biotechnological methods and the provision of in plant breeding is then transferred to Member States of the IAEA and the FAO through training in mutation breeding methods and the provision of technical advice. Moreover, radiation treatment services are provided to foster applications of nuclear techniques in crop improvement programmes of member states and more specifically to render direct support to plant breeders by efficient generation of mutations. Plant materials are standardized prior to radiation exposure to warrant reproducibility of the induced effects within practical limits and a radiosensitivity test is implemented to affirm useful doses for applied objectives of a request. This review deals with irradiation methods applied at the IAEA laboratories for the efficient induction of mutations in seeds, vegetative propagules and tissue and cell cultures and the establishment of genetically variable populations upon which selection of desired traits can be based. 3 tabs., 18 refs. (author)

  11. Mutation Analysis in Classical Phenylketonuria Patients Followed by Detecting Haplotypes Linked to Some PAH Mutations.

    Science.gov (United States)

    Dehghanian, Fatemeh; Silawi, Mohammad; Tabei, Seyed M B

    2017-02-01

    Deficiency of phenylalanine hydroxylase (PAH) enzyme and elevation of phenylalanine in body fluids cause phenylketonuria (PKU). The gold standard for confirming PKU and PAH deficiency is detecting causal mutations by direct sequencing of the coding exons and splicing involved sequences of the PAH gene. Furthermore, haplotype analysis could be considered as an auxiliary approach for detecting PKU causative mutations before direct sequencing of the PAH gene by making comparisons between prior detected mutation linked-haplotypes and new PKU case haplotypes with undetermined mutations. In this study, 13 unrelated classical PKU patients took part in the study detecting causative mutations. Mutations were identified by polymerase chain reaction (PCR) and direct sequencing in all patients. After that, haplotype analysis was performed by studying VNTR and PAHSTR markers (linked genetic markers of the PAH gene) through application of PCR and capillary electrophoresis (CE). Mutation analysis was performed successfully and the detected mutations were as follows: c.782G>A, c.754C>T, c.842C>G, c.113-115delTCT, c.688G>A, and c.696A>G. Additionally, PAHSTR/VNTR haplotypes were detected to discover haplotypes linked to each mutation. Mutation detection is the best approach for confirming PAH enzyme deficiency in PKU patients. Due to the relatively large size of the PAH gene and high cost of the direct sequencing in developing countries, haplotype analysis could be used before DNA sequencing and mutation detection for a faster and cheaper way via identifying probable mutated exons.

  12. Induced mutation for disease resistance in legumes

    International Nuclear Information System (INIS)

    Bravo, A.

    1984-01-01

    Mutation breeding has been used for developing genotypes that may contain resistance to: a) A necrotic strain of common mosaic virus, in common bean (Phaseolus vulgaris L.); b) Soil fungi causing root rots in chickpea (Cicer arietinum L.); c) The fungus Uromyces fabae that causes rust in lentil plants (Lens culinaria). Seeds of these three species were treated with gamma rays in doses of 1,000, 3,000, 6,000, and 9,000 rads. Treated materials and controls were grown during 1979. Chickpea M2 plants were grown in a naturally infested soil with soil-borne fungi. Lentil plants were sprayed with a suspension of spores of the rust fungus. Common bean M2 plants were sprayed with a solution containing virus particles. Ninety-three symptomless chickpea plants were identified in the M2 population. For lentil there were 47 symptomless plants and for common bean, 244 M2 plants with minor virus damage. Eight M3 progenies of chickpea, originated from symptomless M2 plants, had a high rate of survival and showed none or very little damage by root rots. In addition, some morphological changes were detected in other M3 chickpea progenies. Two progenies had larger leaflets, as compared to the control plants and those of other progenies. One progeny showed a more erect growth habit. These new traits have been attributed to genetic changes induced by the radiation treatments. By contrast to these promising results with chickpea no progress has been detected in the plant populations of common bean and lentil. (author)

  13. Induced mutations for human welfare through agriculture

    International Nuclear Information System (INIS)

    Patil, S.A.

    2009-01-01

    Full text: Use of induced mutation for crop improvement started in 1920's. It gained momentum in 1960's when IAEA and FAO started training and guidance and funds were made available for undertaking mutation breeding. IARI established a Gamma Garden and a separate institution was carved by name 'Nuclear Research Laboratory' in 1970's. ICAR Institutes and State Agriculture Universities started using this facility for crop improvement. Similarly, BARC started extending its help for irradiating the seed material specially X-rays and it became one of the major source of generating variability for crop improvement. Induced mutation has resulted in development of more than 3000 varieties of different food, feed, fruit, vegetables and flowers. Apart from direct use of mutants as cultivars, mutants have played a vital role in creating useful variation for application in basic research and gene discovery. It has helped in increasing yield through use of heterosis by inducing male sterility. It has been used for creating useful variation for changing grain composition to improve nutrition and grain quality parameters, for tolerance against abiotic and biotic stresses. Gene sequencing and related technologies have opened up new application of induced mutations. In model organisms induced mutations provide new opportunities for identification of genes/bio-chemical, cellular, developmental or functional pathways. The use of stable isotopes in basic research is of fundamental use in crop improvement. Apart from crop improvement the nuclear technology has been used for numerous other applications in Agriculture such as soil fertility, plant nutrition, use of fertilizer and irrigation, control of insect pest and storage. In recent decades BARC has come in a big way through funding for projects to State Agricultural Universities and ICAR Institutes and has signed MoU's with few of the Agriculture Universities for testing and popularizing their identified field crop varieties in

  14. Induced mutation in tropical fruit trees

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-05-15

    This publication is based on an FAO/IAEA coordinated research project (CRP) and provides insight into the application of induced mutation and in vitro techniques for the improvement of well known fruit trees such as citrus, mango, avocado and papaya, as well as more exotic fruit trees such as litchi, annona, jujube, carambola, pitanga and jaboticaba. The latter are of particular importance due to their adaptation to harsh environments and their high potential as basic food and micronutrient providers for populations in poorer and more remote regions. The findings of the CRP show that application of radiation induced mutation techniques in tropical and subtropical fruit trees can contribute to improving nutritional balance food security, and to enhancing the economic status of growers.

  15. Induced mutation in tropical fruit trees

    International Nuclear Information System (INIS)

    2009-05-01

    This publication is based on an FAO/IAEA coordinated research project (CRP) and provides insight into the application of induced mutation and in vitro techniques for the improvement of well known fruit trees such as citrus, mango, avocado and papaya, as well as more exotic fruit trees such as litchi, annona, jujube, carambola, pitanga and jaboticaba. The latter are of particular importance due to their adaptation to harsh environments and their high potential as basic food and micronutrient providers for populations in poorer and more remote regions. The findings of the CRP show that application of radiation induced mutation techniques in tropical and subtropical fruit trees can contribute to improving nutritional balance food security, and to enhancing the economic status of growers

  16. Molecular analysis of radiation-induced mutations in vitro

    International Nuclear Information System (INIS)

    Kronenberg, A.

    1996-01-01

    This review will focus on the nature of specific locus mutations detected in mammalian cells exposed in vitro to different types of ionizing radiations. Ionizing radiation has been shown to produce a wide variety of heritable alterations in DNA. These range from single base pair substitutions to stable loss or translocation of large portions of whole chromosomes. Data will be reviewed for certain test systems that reveal different mutation spectra. Techniques for the analysis of molecular alterations include applications of the polymerase chain reaction, some of which may be coupled with DNA sequence analysis, and a variety of hybridization-based techniques. The complexity of large scale rearrangements is approached with cytogenetic techniques including high resolution banding and various applications of the fluorescence in situ hybridization (FISH) technique. Radiation-induced mutant frequencies and mutation spectra are a function of the linkage constraints on the recovery of viable mutants for a given locus and test system. 44 refs

  17. Use of induced mutations for potato improvement

    International Nuclear Information System (INIS)

    Kishore, H.; Das, B.; Subramanyam, K.N.; Chandra, R.; Upadhya, M.D.

    1975-01-01

    The investigations aim at the utilization of induced mutations for potato improvement. The effect of γ-rays was tested on selfed seeds and hybrid seeds as well as on tubers of several potato varieties. Chemical mutagens have been successfully employed to produce daylength neutral clones. An attempt to induce resistance against Pseudomonas solanacearum did not give conclusive results. Potato improvement in relation of yield and other characters of economic significance like maturity and attributes of tubers has been handicapped by several technical considerations world over. The crux of the problem lies in the narrow genetic base (variability) for potato breeders to work with. The use of mutation breeding, therefore, offers a good tool for this. Improvement by mutation breeding for the quantitative characters besides the resistance to disease and pest has been demonstrated in other crops like white mustard variety Primex (Anderson and Olsson, 1954), barley (Gustafsson, 1965) and peanut (Gregory, 1956). Keeping these in view and the success we had in isolating photoperiod insensitive types (Upadhaya et al, 1973, 1974) study was enlarged to use mutagens to increase as wide a spectrum as possible of the variability for quantative and qualitative characters. (author)

  18. DNA sequence analysis of X-ray induced Adh null mutations in Drosophila melanogaster

    International Nuclear Information System (INIS)

    Mahmoud, J.; Fossett, N.G.; Arbour-Reily, P.; McDaniel, M.; Tucker, A.; Chang, S.H.; Lee, W.R.

    1991-01-01

    The mutational spectrum for 28 X-ray induced mutations and 2 spontaneous mutations, previously determined by genetic and cytogenetic methods, consisted of 20 multilocus deficiencies (19 induced and 1 spontaneous) and 10 intragenic mutations (9 induced and 1 spontaneous). One of the X-ray induced intragenic mutations was lost, and another was determined to be a recombinant with the allele used in the recovery scheme. The DNA sequence of two X-ray induced intragenic mutations has been published. This paper reports the results of DNA sequence analysis of the remaining intragenic mutations and a summary of the X-ray induced mutational spectrum. The combination of DNA sequence analysis with genetic complementation analysis shows a continuous distribution in size of deletions rather than two different types of mutations consisting of deletions and 'point mutations'. Sequencing is shown to be essential for detecting intragenic deletions. Of particular importance for future studies is the observation that all of the intragenic deletions consist of a direct repeat adjacent to the breakpoint with one of the repeats deleted

  19. Heavy ion induced mutation in arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Tano, Shigemitsu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1997-03-01

    Heavy ions, He, C, Ar and Ne were irradiated to the seeds of Arabidopsis thaliana for inducing the new mutants. In the irradiated generation (M{sub 1}), germination and survival rate were observed to estimate the relative biological effectiveness in relation to the LET including the inactivation cross section. Mutation frequencies were compared by using three kinds of genetic loci after irradiation with C ions and electrons. Several interesting new mutants were selected in the selfed progenies of heavy ion irradiated seeds. (author)

  20. Induced mutations for quantitative traits in rice

    International Nuclear Information System (INIS)

    Chakrabarti, B.N.

    1974-01-01

    The characteristics and frequency of micro-mutations induced in quantitative traits by radiation treatment and the extent of heterozygotic effects of different recessive chlorophyll-mutant-genes on quantitative trait has been presented. Mutagenic treatments increased the variance for quantitative traits in all cases although the magnitude of increase varied depending on the treatment and the selection procedure adopted. The overall superiority of the chlorophyll-mutant heterozygotes over the corresponding wild homozygotes, as noted in consecutive two seasons, was not observed when these were grown at a high level of nitrogen fertiliser. (author)

  1. Improvement of some ornamental plants by induced somatic mutations at National Botanical Research Institute

    International Nuclear Information System (INIS)

    Gupta, M.N.

    1980-01-01

    Research work on improvement of some ornamental plants by induced somatic mutations has been in progress at the National Botanical Research Institute, Lucknow, since 1964. The methods of treatments with gamma rays, detection, isolation and multiplication of induced somatic mutations have been given for Bougainvillea, Chrysanthemum, perennial Portulaca, rose and tuberose. During the last 15 years, a total of 38 new cultivars of different ornamentals evolved by gamna induced somatic mutations have been released. They include Bougainvillea 1; Chrysanthemum 28; perennial portulaca 6; rose 1 and tuberose 2. Descriptions of the original cultivars and their gamma induced mutants are given along with other pertinent details. (author)

  2. Radiation induced mutations in Phaseolus vulgaris L

    International Nuclear Information System (INIS)

    Al-Rubeai, M.A.F.

    1982-01-01

    A selection of various macro- and micro-mutations was undertaken in the M2 generation of Phaseolus vulgaris cultivars after seed exposure to acute gamma radiation doses of 2.5, 5, 7, 10 and 15 Kr. The chlorophyll mutation was positively correlated with dose. Nevertheless, the highest frequency was at 7 Kr. Several interesting morphological mutants were observed. There were dwarf, stiff stem, shiny small leaf, narrow leaf and green giant mutants. Two selected micromutants were superior in seed yield capacity to their parents. The high yields were related to the high number of pods per plant. In 'The Prince' (seed color: red with beige marbling) several mutants with seeds of black color marbled with beige were selected. These seeds gave M3 segregants exhibiting a range of seed colors including white. Many of these M3 plants were short, early flowering and highly sterile. The work demonstrated that the pigmentation character can readily be changed, and confirmed that the variability induced by radiation can be exploited to obtain desirable mutations. (Author) [pt

  3. Tumor‐associated DNA mutation detection in individuals undergoing colonoscopy

    OpenAIRE

    Fleshner, Phillip; Braunstein, Glenn D.; Ovsepyan, Gayane; Tonozzi, Theresa R.; Kammesheidt, Anja

    2017-01-01

    Abstract The majority of colorectal cancers (CRC) harbor somatic mutations and epigenetic modifications in the tumor tissue, and some of these mutations can be detected in plasma as circulating tumor DNA (ctDNA). Precancerous colorectal lesions also contain many of these same mutations. This study examined plasma for ctDNA from patients undergoing a screening or diagnostic colonoscopy to determine the sensitivity and specificity of the ctDNA panel for detecting CRC and precancerous lesions. T...

  4. Performance of mitochondrial DNA mutations detecting early stage cancer

    International Nuclear Information System (INIS)

    Jakupciak, John P; Srivastava, Sudhir; Sidransky, David; O'Connell, Catherine D; Maragh, Samantha; Markowitz, Maura E; Greenberg, Alissa K; Hoque, Mohammad O; Maitra, Anirban; Barker, Peter E; Wagner, Paul D; Rom, William N

    2008-01-01

    Mutations in the mitochondrial genome (mtgenome) have been associated with cancer and many other disorders. These mutations can be point mutations or deletions, or admixtures (heteroplasmy). The detection of mtDNA mutations in body fluids using resequencing microarrays, which are more sensitive than other sequencing methods, could provide a strategy to measure mutation loads in remote anatomical sites. We determined the mtDNA mutation load in the entire mitochondrial genome of 26 individuals with different early stage cancers (lung, bladder, kidney) and 12 heavy smokers without cancer. MtDNA was sequenced from three matched specimens (blood, tumor and body fluid) from each cancer patient and two matched specimens (blood and sputum) from smokers without cancer. The inherited wildtype sequence in the blood was compared to the sequences present in the tumor and body fluid, detected using the Affymetrix Genechip ® Human Mitochondrial Resequencing Array 1.0 and supplemented by capillary sequencing for noncoding region. Using this high-throughput method, 75% of the tumors were found to contain mtDNA mutations, higher than in our previous studies, and 36% of the body fluids from these cancer patients contained mtDNA mutations. Most of the mutations detected were heteroplasmic. A statistically significantly higher heteroplasmy rate occurred in tumor specimens when compared to both body fluid of cancer patients and sputum of controls, and in patient blood compared to blood of controls. Only 2 of the 12 sputum specimens from heavy smokers without cancer (17%) contained mtDNA mutations. Although patient mutations were spread throughout the mtDNA genome in the lung, bladder and kidney series, a statistically significant elevation of tRNA and ND complex mutations was detected in tumors. Our findings indicate comprehensive mtDNA resequencing can be a high-throughput tool for detecting mutations in clinical samples with potential applications for cancer detection, but it is

  5. RADIA: RNA and DNA integrated analysis for somatic mutation detection.

    Directory of Open Access Journals (Sweden)

    Amie J Radenbaugh

    Full Text Available The detection of somatic single nucleotide variants is a crucial component to the characterization of the cancer genome. Mutation calling algorithms thus far have focused on comparing the normal and tumor genomes from the same individual. In recent years, it has become routine for projects like The Cancer Genome Atlas (TCGA to also sequence the tumor RNA. Here we present RADIA (RNA and DNA Integrated Analysis, a novel computational method combining the patient-matched normal and tumor DNA with the tumor RNA to detect somatic mutations. The inclusion of the RNA increases the power to detect somatic mutations, especially at low DNA allelic frequencies. By integrating an individual's DNA and RNA, we are able to detect mutations that would otherwise be missed by traditional algorithms that examine only the DNA. We demonstrate high sensitivity (84% and very high precision (98% and 99% for RADIA in patient data from endometrial carcinoma and lung adenocarcinoma from TCGA. Mutations with both high DNA and RNA read support have the highest validation rate of over 99%. We also introduce a simulation package that spikes in artificial mutations to patient data, rather than simulating sequencing data from a reference genome. We evaluate sensitivity on the simulation data and demonstrate our ability to rescue back mutations at low DNA allelic frequencies by including the RNA. Finally, we highlight mutations in important cancer genes that were rescued due to the incorporation of the RNA.

  6. Laser desorption mass spectrometry for point mutation detection

    Energy Technology Data Exchange (ETDEWEB)

    Taranenko, N.I.; Chung, C.N.; Zhu, Y.F. [Oak Ridge National Lab., TN (United States)] [and others

    1996-10-01

    A point mutation can be associated with the pathogenesis of inherited or acquired diseases. Laser desorption mass spectrometry coupled with allele specific polymerase chain reaction (PCR) was first used for point mutation detection. G551D is one of several mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene present in 1-3% of the mutant CFTR alleles in most European populations. In this work, two different approaches were pursued to detect G551D point mutation in the cystic fibrosis gene. The strategy is to amplify the desired region of DNA template by PCR using two primers that overlap one base at the site of the point mutation and which vary in size. If the two primers based on the normal sequence match the target DNA sequence, a normal PCR product will be produced. However, if the alternately sized primers that match the mutant sequence recognize the target DNA, an abnormal PCR product will be produced. Thus, the mass spectrometer can be used to identify patients that are homozygous normal, heterozygous for a mutation or homozygous abnormal at a mutation site. Another approach to identify similar mutations is the use of sequence specific restriction enzymes which respond to changes in the DNA sequence. Mass spectrometry is used to detect the length of the restriction fragments generated by digestion of a PCR generated target fragment. 21 refs., 10 figs., 2 tabs.

  7. Laser desorption mass spectrometry for point mutation detection

    Energy Technology Data Exchange (ETDEWEB)

    Taranenko, N.I.; Chung, C.N.; Zhu, Y.F. [Oak Ridge National Lab., TN (United States)] [and others

    1996-12-31

    A point mutation can be associated with the pathogenesis of inherited or acquired diseases. Laser desorption mass spectrometry coupled with allele specific polymerase chain reaction (PCR) was first used for point mutation detection. G551D is one of several mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene present in 1-3% of the mutant CFTR alleles in most European populations. In this work, two different approaches were pursued to detect G551D point mutation in the cystic fibrosis gene. The strategy is to amplify the desired region of DNA template by PCR using two primers that overlap one base at the site of the point mutation and which vary in size. If the two primers based on the normal sequence match the target DNA sequence, a normal PCR product will be produced. However, if the alternately sized primers that match the mutant sequence recognize the target DNA, an abnormal PCR product will be produced. Thus, the mass spectrometer can be used to identify patients that are homozygous normal, heterozygous for a mutation or homozygous abnormal at a mutation site. Another approach to identify similar mutations is the use of sequence specific restriction enzymes which respond to changes in the DNA sequence. Mass spectrometry is used to detect the length of the restriction fragments by digestion of a PCR generated target fragment. 21 refs., 10 figs., 2 tabs.

  8. Induced mutation breeding in fruit trees

    International Nuclear Information System (INIS)

    Sanada, Tetsuro

    1988-01-01

    The black spot disease of Japanese pear is the most serious disease, and Nijusseiki which is one of the leading cultivars of Japanese pear is known to be susceptible to the disease. One branch of a tree planted at the distance of 53 m from a Co-60 source (15 R/day) was selected as a mutant resistant to the disease in 1981, as the spraying of fungicide was reduced when the pathogen was naturally inoculated. The symptom of black spot disease on the mutant observed under field conditions for the period of 5 years after the selection was minimal. The characteristics and the resistance of this mutant were examined. The development of a simple and reliable selection method is essential for mutation breeding. A selection method using a phytotoxin solution was developed. The induced mutant was obviously different from the original Nijusseiki in the susceptibility to the disease, but its resistance was medium. The faint brown spots observed on the leaves and fruit skins of the mutant were due to the aggregation of cytoplasm only in epidermal cells. By the selection method developed, about 500 shoots can be screened in a day. (Kako, I.)

  9. Radiation-Induced Mutation and Crop Improvement

    International Nuclear Information System (INIS)

    Lee, Y. I.; Song, H. S.; Kim, J. S.; Shin, I. C.; Lee, S. J.

    1987-01-01

    Radiation induced mutations have not only been used directly as a cultivar in crop plants, but also indirectly as a genetic resource that is essential to conventional plant breeding. M 1 plant survivals of three rice cultivars treated with gamma rays of 200-350 Gy varied from 30-40%. The survival of the Sawing variety was less sensitive to radiation, but its fertility was more sensitive in comparison with Seomjin and Sponging. Various dwarf or semi-dwarf mutants and early=matured mutants have been selected in the M 2 and M 3 generations of the three rice cultivars irradiated with gamma rays. Other desirable mutants also have been selected, such as high-yielding, high-tailoring and disease-resistant. The genetic nature of most of the selected short calm and earliness mutants was fixed in M 2 or M 3 generations. Dwarfism of IEAR 308 and Monogynol 10 were found to have a single recessive gene. However, the dwarf of IEAR 308 has a recessive deficit phenomenon. The highest genetic heritability of plant height was observed in the cross combination of Monogynol 10 Χ Pawling

  10. Radiation-induced mutations in fish

    International Nuclear Information System (INIS)

    Schroeder, J.H.

    1980-01-01

    X-ray-induced mutations in teleostean fish were studied from the point of social behavior. A significant reduction in male aggression was found in the postirradiated F 1 generation after the irradiation of parental oogonia and spermatogonia, with 2 x 500 R (24 hr apart) of x-rays, but did not alter the aggression of F 1 females. A study on backcross generation of irradiated line fitted with a two-factor model of dominant genetic factors, high- and low-aggressive, which co-acted additively in repressing the male aggression. Social cohesiveness was compared between F 1 convict cichlides (C. nigrofasciatum) exposed by 0, 250, 500, 750, 1000, and 2000 R of x-rays. The best response was observed in males with 500 R and in females with 750 R. While an increase in cohesiveness was observed in F 1 males with 500 R, the cohesiveness of F 1 females decreased with 750 and 200 R, suggesting that the increase in male was associated with a reduction of inter-male aggression. A new ''guppy male courtship activity test'' was carried out in the offsprings of irradiated guppy, maintained in seawater and in freshwater. The mean values of both the frequency and the duration of four behavioral traits of the male guppy increased in postirradiated F 1 generation of the seawater substrain but were unchanged in that of freshwater's. In F 2 generation the mean values of the same behavioral characters decreased in both seawater and freshwater substrains. (Nakanishi, T.)

  11. Induced mutations for soybean rust resistance

    International Nuclear Information System (INIS)

    Smutkupt, S.; Wongpiyasatid, A.; Lamseejan, S.

    1983-01-01

    Soybean mutation experiments for inducing rust resistance in the cultivars G 8375, Wakashima mutant number 10, Taichung N, S.J.2, S.J.4, BM 50, BM 98, G 8377, G 8586 and G 8587 have been carried out since 1979. Six pods from each of 4438 control and 43,907 M 1 plants were randomly harvested. M 2 seeds of each cultivar of different doses were bulked (M 2 bulk). In addition, 270 good M 1 plants were selected and threshed singly (M 2 single). M 2 -bulk and M 2 -single seeds were advanced to M 3 . Both, M 3 -bulk and M 3 -single plants, together with the remaining M 2 -bulk seeds were screened for rust resistance in the rainy season of 1980 in Nong Hoi Valley (altitude about 1000 m above sea level) and at Mae Joe Station, both in Chiang Mai Province (latitude 18 deg. 31'-19 deg. N). Based on the IWGSR rating system, soybean plants with slow growth of rust were selected from both locations. The results were as follows: Six plants were selected from a total of 2802 control plants, and 115 from a total of 28,834 M 2 and M 3 plants. Further evaluation of these selections for rust resistance will be carried out in the rainy season of 1981 in Nong Hoi Valley, Chiang Mai. (author)

  12. Induced mutation breeding by fast neutron

    International Nuclear Information System (INIS)

    Chen Zhengba; You Risheng

    1988-09-01

    The high-yield and long-grain new variety 'Zhongtie 31' was developed through five generations after irradiation of the rice variety 'Tieqiu 15' dried seeds by 14 MeV fast neutrons with a fluence of (1.33 ∼ 3.33) x 10 11 neutrons cm -2 . It matured earlier 3 to 5 days, the plant is higher 10 cm, bigger ear, more grain than its original variety 'tieqiu 15', and the yield increased by 19.2% to 30.7%. The source of new variety 'Zhongtie 31' was proved by the isoenzyme genetics. In field test, it increased by 7% to 10% as compared with high-yield variety 'Guichao No.2' and the hybrid rive 'Shanyou No.2', and is more palatable. The new variety was initiated by irradiation mutagensis routine rice, its well-grown and bumper-yield performances may be compared favourably with hybrid rice variety. In July 1986, the new variety 'Zhongtie 31' was obtained by inducing mutation with fast neutron. The same year, the planted area of 'Zhongtie 31' has achieved upto 250 thousand mu (1.67 x 10 8 cm 2 )

  13. Hyperthermia-induced alteration of yeast susceptibility to mutation

    International Nuclear Information System (INIS)

    Mitchel, R.E.J.; Morrison, D.P.

    1985-01-01

    Diploid yeast (s. cerevisiae) were examined for alterations in susceptibility to induced mutation following hyperthermia treatment. In cells grown at 23 0 C, a non-lethal heat exposure (38 0 C, 30 min) markedly suppressed mutation induced by a subsequent non-killing dose of MNNG of MNU. Mutation by ENU, 8-MOP + UVA, or γ-rays was not affected. An intermediate level of mutation suppression was observed for mutation by 254nm UV or MMS. Mutation by MNNG was not suppressed by the same heat treatment delivered after the mutagen exposure. In a split dose experiment (two MNNG treatments separated by a heat exposure) no suppression of mutation was observed. Treatment with cycloheximide mimicked the effect of heat treatment. These data suggest that mutation induction by MNNG or MNU is protein synthesis dependent, i.e. an error-prone repair system is induced by exposure to MNNG or MNU but not by ENU, 8-MOP+UVA or γ-irradiation. We propose that hyperthermia treatment, by inducing stress protein synthesis at the expense of normal protein synthesis, precludes induction of this error-prone system. Therefore, in heat treated cells, DNA lesions produced by MNNG or MNU exposure must be resolved by an essentially constitutive system which is less error-prone than the inducible one

  14. Induced mutations of winged bean in Ghana

    Energy Technology Data Exchange (ETDEWEB)

    Klu, G Y.P.; Quaynor-Addy, M; Dinku, E; Dikumwin, E [National Nuclear Research Institute, Ghana Atomic Energy Commission, Legon (Ghana)

    1989-07-01

    Winged bean (Psophocarpus tetragonolobus (L.) D.C.) was introduced into Ghana about two decades ago and not long after a high quality baby food was compounded from it. Germplasm collections are established at the Kade Agricultural Research Station of the University of Ghana and the University of Cape Coast. In 1980 a mutation breeding project was initiated at the University of Cape Coast under FAO/IAEA research contract and among various mutants a single erect stem mutant, a multiple branched bush type and a mutant with extra long pods were obtained. A similar programme was started at the National Nuclear Research Centre Kwabenya in 1982. Seeds of accessions UPS 122 and Kade 6/16 were gamma irradiated (100-400 Gy). In M{sub 2} a mutant was obtained that did not flower throughout a growing period of five months. This mutant had very few leaves but developed an underground tuber weighing ca. 100 g. The parent, UPS 122, although normally tuber producing did not form tubers at Kwabenya within the period studied. In M{sub 3}, mutants with variations in seed size and seed coat colour have been detected.

  15. R and D activities on radiation induced mutation breeding

    International Nuclear Information System (INIS)

    Lapade, A.G.; Asencion, A.B.; Santos, I.S.; Grafia, A.O.; Veluz, AM.S.; Barrida, A.C.; Marbella, L.J.

    1996-01-01

    This paper summarizes the accomplishments, prospects and future plans of mutation breeding for crop improvement at the Philippine Nuclear Research Institute (PNRI). Mutation induction has become a proven way creating variation within a crop variety and inducing desired attributes that cannot be found in nature or have been lost during evolution. Several improved varieties with desirable traits were successfully developed through induced mutation breeding at our research institute. In rice, mutation breeding has resulted in the development of new varieties: (1) PARC 2, (2) Milagrosa mutant, (3) Bengawan mutant and (4) Azmil mutant. Mutation breeding in leguminous crops has led to the induction of an improved L 114 soybean mutant that is shorter that the original variety but yield about 40% more. Several PAEC mungbean varieties characterized with long pods that are non-shattering were also induced. In asexually propagated crops, an increase in yield and chlorophyll mutants were obtained in sweet potatos. Likewise, chlorophyll mutant which look-like 'ornamental bromeliads' and a mutant with reduced spines have been developed in pineapple Queen variety. At present, we have started a new project in mutation breeding in ornamentals. Tissue culture is being utilized in our mutation breeding program. In the near future, radiation induced mutagenesis coupled with in vitro culture techniques on protoplast culture and somatic hybridization will be integrated into our mutation breeding program to facilitate the production of new crop varieties. (author)

  16. Achievements and trends of using induced mutations in crop improvement

    International Nuclear Information System (INIS)

    Nichterlein, K.; Maluszynski, M.; ); Bohlmann, H.; Nielen, S.; )

    2000-01-01

    Mutation techniques have been employed for the genetic improvement of crops and ornamentals leading to the official release of more than 2200 improved varieties. Some of them have made a major impact on crop productivity and achieved great economic success. Induced mutations play an important role in plant genome research to understand the function of genes aiming to improve food security and diversity. (author)

  17. Sensitive and fast mutation detection by solid phase chemical cleavage

    DEFF Research Database (Denmark)

    Hansen, Lise Lotte; Justesen, Just; Kruse, Torben A

    1996-01-01

    We have developed a solid phase chemical cleavage method (SpCCM) for screening large DNA fragments for mutations. All reactions can be carried out in microtiterwells from the first amplification of the patient (or test) DNA through the search for mutations. The reaction time is significantly...... reduced compared to the conventional chemical cleavage method (CCM), and even by using a uniformly labelled probe, the exact position and nature of the mutation can be revealed. The SpCCM is suitable for automatization using a workstation to carry out the reactions and a fluorescent detection-based DNA...

  18. High-resolution melting curve analysis for rapid detection of mutations in a Medaka TILLING library

    Directory of Open Access Journals (Sweden)

    Deguchi Tomonori

    2010-09-01

    Full Text Available Abstract Background During the last two decades, DNA sequencing has led to the identification of numerous genes in key species; however, in most cases, their functions are still unknown. In this situation, reverse genetics is the most suitable method to assign function to a gene. TILLING (Targeting Induced Local Lesions IN Genomes is a reverse-genetic strategy that combines random chemical mutagenesis with high-throughput discovery of the induced mutations in target genes. The method has been applied to a variety of plant and animal species. Screening of the induced mutations is the most important step in TILLING. Currently, direct sequencing or nuclease-mediated screening of heteroduplexes is widely used for detection of mutations in TILLING. Both methods are useful, but the costs are substantial and turnaround times are relatively long. Thus, there is a need for an alternative method that is of higher throughput and more cost effective. Results In this study, we developed a high resolution melting (HRM assay and evaluated its effectiveness for screening ENU-induced mutations in a medaka TILLING library. We had previously screened mutations in the p53 gene by direct sequencing. Therefore, we first tested the efficiency of the HRM assay by screening mutations in p53, which indicated that the HRM assay is as useful as direct sequencing. Next, we screened mutations in the atr and atm genes with the HRM assay. Nonsense mutations were identified in each gene, and the phenotypes of these nonsense mutants confirmed their loss-of-function nature. Conclusions These results demonstrate that the HRM assay is useful for screening mutations in TILLING. Furthermore, the phenotype of the obtained mutants indicates that medaka is an excellent animal model for investigating genome stability and gene function, especially when combined with TILLING.

  19. Studies on induced mutations in garlic

    International Nuclear Information System (INIS)

    Selvaraj, N.; Natarajan, S.; Ramaraj, B.

    2001-01-01

    Garlic (Allium sativum L.) is the second most widely cultivated Allium - after onion. It has been recognised world-wide as a valuable spice for foods and a popular remedy for various ailments and physiological disorders. The available types of garlic exhibit low variability due to repeated vegetative propagation. As garlic flowers are mostly sterile, restoration of fertility is a difficult process and hence there exists little scope for genetic improvement through hybridization. Induced mutagenesis with gamma rays has helped to overcome these genetic barriers. Ethyl methanesulphonate (EMS) and their combination treatments attempted to improve bulb yield in garlic varieties 'Mettupalayam' and 'Ooty-1' at the Horticultural Research Station, Ooty in Nilgiris. Based on radiosensitivity studies, two doses of gamma rays (2.5 and 5.0 Gy), four concentrations of EMS (15, 20, 25 and 30 mM for 8 h at temperature 25±2 deg. C) and four combined treatments (2.5 Gy + 20 mM, 2.5 Gy + 25 mM, 5.0 Gy + 20 mM and 5.0 Gy + 25 mM) were employed. Garlic bulb and clove characteristics and the varietal response were significantly influenced by the physical, chemical mutagens and their combination treatments. The spectrum of chlorophyll mutants identified in the present study are comprised of, albina, chlorina, straita, viridis and xantha. The proportion of the various mutants varied with the varieties and mutagen treatments. Increasing doses of gamma rays, EMS or combination treatments increased the rate of lethality, injury and clove sterility of treated populations. Mutations for plant, leaf and shoot morphology were more frequent than bulb characters in both varieties. Non-viable mutants were dose dependant and this increased with higher doses. Gamma treatments caused more non-viable mutants (mottled and crinkled leaves) followed by combined and EMS treatments

  20. Induced mutation for tungro resistance in rice

    International Nuclear Information System (INIS)

    Ikeda, R.; Yumol, R.R.; Taura, S.

    2001-01-01

    Tungro is the most serious virus disease of rice in South and Southeast Asia. It is a composite disease of two kinds of viruses, rice tungro bacilliform virus (RTBV) and rice tungro spherical virus (RTSV). Damage to the plant is mostly caused by RTBV, while RTSV acts to facilitate RTBV acquisition and transmission by insect vector. Both viruses are transmitted mainly by green leafhopper (GLH). Resistance to GLH is common in rice germplasm but extremely rare for the two viruses. To induce mutations for tungro resistance, a susceptible variety IR22 was treated with N-methyl-N-nitrosourea (MNH) following the procedure of Satoh and Omura. The panicles of rice variety 'IR22' were soaked in 1 mM MNH solution for 45 minutes at 16 to 18 hours after flowering. Two thousand six hundred and forty fertile M 1 plants were produced. From these plants M 2 lines with 10 or more seedlings were planted in the field to evaluate their reaction against tungro under natural conditions in the 1990 dry season on the IRRI central research farm, Los Banos, the Philippines. Of these, 124 M 2 lines were selected by visual evaluation. Five plants were harvested individually from each selected line. A bulk was also made from all the remaining plants in the line. In the M 3 generation, each family consisted of five sister lines and one bulked line. One line (M 3 -723) showed no tungro symptoms and its related bulk segregated for resistance but all other M 3 lines from the same family were susceptible to tungro. The resistant line, M 3 -723, showed low infection with RTBV and RTSV when leaves were tested by enzyme-linked immunosorbent assay (ELISA) to diagnose tungro infection. All M 4 lines from M 3 -723 showed uniform resistance in the field. They were not infected with RTBV and were resistant to RTSV infection

  1. 21 CFR 866.5900 - Cystic fibrosis transmembrane conductance regulator (CFTR) gene mutation detection system.

    Science.gov (United States)

    2010-04-01

    ... regulator (CFTR) gene mutation detection system. 866.5900 Section 866.5900 Food and Drugs FOOD AND DRUG...) gene mutation detection system. (a) Identification. The CFTR gene mutation detection system is a device... Guidance Document: CFTR Gene Mutation Detection System.” See § 866.1(e) for the availability of this...

  2. Development of Trombay pulse crop varieties mutation through induced mutation

    International Nuclear Information System (INIS)

    Dhole, V.J.; Reddy, K.S.

    2016-01-01

    The food prices including pulses were beginning to increase from 2008, something that was not expected to happen before 2020. It was due to climate change, a scarcity of good arable land, water and nutrients. With these obstacles, we must produce almost double than what we are producing now to achieve food security by 2050. It can be achieved through crop improvement. Crop improvement is the art and science of changing the genetic make of crop plant in desire direction through various method of plant breeding. Mutation breeding is one of the techniques which utilize the physical and chemical mutagens to create genetic variability. Till date more than 3200 mutant varieties have been developed worldwide in which two physical mutagens i.e. X-rays and gamma rays have major contributions. Bhabha Atomic Research Centre is one of the leading institutes in India where nuclear energy is used for crop improvement, which resulted in to development of 43 improved high yielding varieties in different crops including 19 varieties of pulse crops. These varieties are contributing significantly to production of pulses and ultimately to national food security. (author)

  3. Induced mutations for improvement of grain legume production II

    International Nuclear Information System (INIS)

    1982-02-01

    Out of 18 papers presented, 15 fall within the INIS subject scope. Other topics covered were: mutagenic efficiency of ethylmethane sulphonate in soybean; induced mutations for rust resistance in soybean; and nitrogen fixation-potentials for improvement in legumes

  4. Use of induced mutations in soybean breeding

    International Nuclear Information System (INIS)

    Zakri, A.H.; Jalani, B.S.; Ng, K.F.

    1981-01-01

    Artificial induction of mutation in plants is carried out using #betta#-irradiation and ethyl metanesulphonate (EMS) to expand the genetic variability of locally-grown soybean. This aspect of mutation breeding complements of conventional breeding approach undertaken by the Joint Malaysia Soybean Breeding Project group. Recovery of agronomically-important mutants such as earliness, lateness, bigger seed size and improved plant architecture were recorded. The significance of these findings is discussed. (author)

  5. Detecting negative selection on recurrent mutations using gene genealogy

    Science.gov (United States)

    2013-01-01

    Background Whether or not a mutant allele in a population is under selection is an important issue in population genetics, and various neutrality tests have been invented so far to detect selection. However, detection of negative selection has been notoriously difficult, partly because negatively selected alleles are usually rare in the population and have little impact on either population dynamics or the shape of the gene genealogy. Recently, through studies of genetic disorders and genome-wide analyses, many structural variations were shown to occur recurrently in the population. Such “recurrent mutations” might be revealed as deleterious by exploiting the signal of negative selection in the gene genealogy enhanced by their recurrence. Results Motivated by the above idea, we devised two new test statistics. One is the total number of mutants at a recurrently mutating locus among sampled sequences, which is tested conditionally on the number of forward mutations mapped on the sequence genealogy. The other is the size of the most common class of identical-by-descent mutants in the sample, again tested conditionally on the number of forward mutations mapped on the sequence genealogy. To examine the performance of these two tests, we simulated recurrently mutated loci each flanked by sites with neutral single nucleotide polymorphisms (SNPs), with no recombination. Using neutral recurrent mutations as null models, we attempted to detect deleterious recurrent mutations. Our analyses demonstrated high powers of our new tests under constant population size, as well as their moderate power to detect selection in expanding populations. We also devised a new maximum parsimony algorithm that, given the states of the sampled sequences at a recurrently mutating locus and an incompletely resolved genealogy, enumerates mutation histories with a minimum number of mutations while partially resolving genealogical relationships when necessary. Conclusions With their

  6. Induced mutations for crop improvement- the generation next

    International Nuclear Information System (INIS)

    Bhatia, C.R.

    2000-01-01

    Experiments to use induced mutations for the improvement of crop plants were initiated in the country in mid nineteen fifties. After forty five years and reasonably good success stories, it is no longer an attractive subject for bright young graduate students. The areas of intellectually satisfying, contemporary, plant genetics based on induced mutations that can also bring social and commercial benefits are identified. These are: nodulation mutants in legumes, altering fatty acid composition in oil crops, modification of root characters, altering host-pathogen interactions, flowering time, day length insensitivity and some changes in modulation pattern involve mutations

  7. Characterization of carbon ion-induced mutations in Arabidopsis thaliana

    International Nuclear Information System (INIS)

    Shikazono, N.; Suzuki, C.; Kitamura, S.; Watanabe, H.; Tano, S.; Tanaka, A.

    2003-01-01

    Full text: Irradiation of Arabidopsis thaliana by carbon ions was carried out to investigate the mutational effect of ion particles in higher plants. The averaged mutation rate of carbon ions was 2.0 X 10 -6 / Gy, which was 18-fold higher than that of electrons. PCR analysis of the carbon ion-induced mutants showed that, out of 28 mutant alleles, 14 had point-like mutations within the gene, while 14 contained large structural alterations. In the case of 12 electron-induced mutants, 9 had point-like mutations within the gene, while 3 contained large structural alterations. These results suggest that carbon ions are more likely to induce large structural alterations compared with electrons. Further sequence analysis revealed that most of the point-like mutations induced by carbon ions were short deletions. In the case of rearrangements, DNA strand breaks were found to be rejoined using, if present, short homologous sequences for both types of radiation. After carbon ion-irradiation, small deletions were frequently observed around the breakpoints, whereas duplications of terminal sequence were found after electron-irradiation. These results suggest that non-homologous end joining (NHEJ) pathway operates after plant cells are exposed to both ion particles and electrons but that different mode of rejoining deals with the broken ends produced by each radiation. From the present results, it seems reasonable to assume that carbon ions could predominantly induce null mutations in Arabidopsis. The fact that the molecular nature of carbon ion-induced mutation was different from that of electrons and that the molecular mechanisms of cells to induce mutations appeared to be also different implicates that ion particle is not only valuable as a new mutagen but also useful as a new tool to study repair mechanisms of certain types of DNA damage

  8. Effect of hsm mutations enhancing spontaneous mutability on induced mutagenesis and mitotic recombination in Saccharomyces cerevisiae yeast

    International Nuclear Information System (INIS)

    Fedorova, I.V.; Koval'tsova, S.V.; Ivanov, E.L.

    1993-01-01

    The authors have studied the effect of five nonallelic hms1-hms5 mutations on the incidence of direct mutations in loci ADE1 and ADE2, induced by UV-radiation, 6-hydroxyl-aminopurine, and nitrosomethylurea. All hms mutants were found to be insensitive to the lethal action of these mutagens. The frequency of UV-induced mutations to adenine dependence was increased in mutants hsm2-1, hsm3-1, hsm5-1, and particularly in hsm1-1, but remained unchanged in hsm4-1 compared to HSM. Mutagenesis induced by 6-hydroxylaminopurine was increased in all mutants studied, particularly in mutant hsm3-1. The authors did not detect any appreciable effect of hsm mutations on mutagenesis induced by nitrosomethylurea. The frequency of spontaneous mitotic conversion to prototrophy was studied in diploids heteroallelic to gene ADE2 and homo- and heterozygous for hsm mutations. Mutation hsm5-1 considerably increased the frequency of conversion for all heteroalleles studied, mutations hsm1-1 and hsm3-1 also considerably increased the conversion frequency, while mutations hsm1-1 and hsm4-1 had little effect on this process. The study of the properties of hsm mutations revealed joint genetic control of spontaneous and induced mutagenesis and recombination in yeast. The possibility that hsm mutations belong to the class of mutations impairing correction of unpaired DNA bases is discussed. 25 refs., 3 figs., 3 tabs

  9. Dew inspired breathing-based detection of genetic point mutation visualized by naked eye

    Science.gov (United States)

    Xie, Liping; Wang, Tongzhou; Huang, Tianqi; Hou, Wei; Huang, Guoliang; Du, Yanan

    2014-09-01

    A novel label-free method based on breathing-induced vapor condensation was developed for detection of genetic point mutation. The dew-inspired detection was realized by integration of target-induced DNA ligation with rolling circle amplification (RCA). The vapor condensation induced by breathing transduced the RCA-amplified variances in DNA contents into visible contrast. The image could be recorded by a cell phone for further or even remote analysis. This green assay offers a naked-eye-reading method potentially applied for point-of-care liver cancer diagnosis in resource-limited regions.

  10. Radiation-induced mutation breeding of papaya

    Energy Technology Data Exchange (ETDEWEB)

    Chan, Y. K. [Horticulture Research Centre, Malaysian Agricultural Research and Development Institute (MARDI), Kuala Lumpur (Malaysia)

    2009-05-15

    Irradiation-induced mutation breeding of papaya commenced at the Malaysian Agricultural Research and Development Institute (MARDI) in August, 2000. This research was initiated under a Coordinated Research Project (CRP - D23023) with assistance from the International Atomic Energy Agency (IAEA). In the preliminary dosimetry study, seeds from two local papaya varieties, Sekaki and Eksotika were irradiated, either as dry seeds or as pre-soaked seeds (soaked overnight in water and surface-dried) with radiation doses ranging from 0 to 300 Gy. 100 Gy dose was lethal for all wet presoaked seeds while dry seed did not show loss of viability, even at 300 Gy. From the growth data it was estimated that dose of 525 Gy reduced shoot elongation by 50%, and this dose was recommended for mass irradiation of dry seeds. For wet, pre-soaked seeds results indicated that 42.5 Gy was the optimal dose for mass irradiation. At this dose, both seeds germination and seedlings growth were reduced by 50%. In a massive irradiation experiment 2,000 Eksotika seeds were irradiated at 42.5 Gy (pre-soaked) and another 2,000 at 525 Gy (dry). In the M2 population, numerous physiological defects were observed, including stem splitting, leaf variegation and puckering, and crinkled dwarfs. In the M3 population, a wide variability was recorded for a number of traits. M3 seedlings derived from presoaked seeds irradiated a low 42.5 Gy dose presented a high number of plants that were shorter and more vigorous in leaf development compared to those irradiated at 525 Gy and to non-irradiated control seedlings. The distribution patterns of M3 progenies for nine quantitative field characters showed great variation, often exceeding the limits of the control population. There appears to be good prospects in improving Eksotika papaya especially in the development of dwarf trees with lower fruit bearing stature, higher total soluble solids in fruits and larger fruit size. Several M2 and M3 putative mutants also

  11. Induced mutations in pomoid trees breeding

    International Nuclear Information System (INIS)

    Hamed, Faysal

    1986-01-01

    Induction of mutations in fruit trees by ionizing radiation complements a cross-breeding program. The objectives are: 1) the improvements of methods of induction, identification and selection of useful mutations, and 2) the initiation of useful mutations either for immediate use as improved cultivars or as a parent material for conventional cross-breeding. The induction of mutants in pomoid fruits, with special emphasis on apple, was realized by gamma-ray treatment of dormant scions subsequently propagated on a rootstoch in the nursery. The aim was to obtain compacts, presuming the feasibility of selecting compact shoots formed by the irradiated scions in the first vegetative generation and also assuming that chance of finding (e.g. fruit mutants) would be thus increased rather than lessened. Selection was carried out on one-season old shoots, formed on the same material for two or three seasons, by using a cut-back at the end of the first and second season. The procedure was highly effective. Moderate exposures, resulting in 60% survival gave high mutation frequencies. Buds 6-10 on the primary shoot gave higher frequencies of recognizable mutations than either buds 1-5 or 11-15. Preliminary results seem to indicate that, at least in some apple cultivars, there is opportunity to obtain compact growth types with good biological characteristics. 8 refs. (author)

  12. 50 Detecting adenosine triphosphatase 6 point mutations that may ...

    African Journals Online (AJOL)

    mutations at codons for the key residues Lys 260, Leu263, Gln266, Ser769 .... agarose gel and visualized under UV transillumination after treatment with ..... Li, W., Mo, W., Shen, D., Sun, L., Wang, J., Lu, S., Gitschier, J.M. & Zhou, B. (2005) Yeast ... Nagamune, K., Beatty, W.L., & Sibley, D. (2007) Artemisinin induces Calcium ...

  13. Induced mutations for disease resistance in wheat

    International Nuclear Information System (INIS)

    Cerny, J.; Hanis, M.; Hanisova, A.; Knytl, V.; Sasek, A.

    1983-01-01

    Mutation induction has been used over a period of 20 years to obtain mutants of wheat with improved disease resistance. 34 wheat cultivars have been treated with X-rays, gamma rays, thermal neutrons or EMS. A great number of mutants were selected. Their mutational origin was verified by electrophoretic analysis of gliadin spectra. Resistances have been confirmed over several generations. None of the mutants have been released yet for commercial cultivation because of shortcomings in yield or susceptibility to other diseases. The use of mutants in cross-breeding is considered. (author)

  14. Rice breeding with induced mutations in France

    Energy Technology Data Exchange (ETDEWEB)

    Marie, R [Station d' Amelioration des Plantes, Institut National de Recherches Agronomiques, Montpellier (France)

    1970-03-01

    Mutation experiments with rice at Montpellier yielded strains with improved lodging resistance, grain size, maturing time, milling quality and other characters. The general performance of these mutant strains was tested in field trials. Further mutagenic treatments were made to improve the high-yielding short grain varieties with regard to grain quality and seed dormancy. (author)

  15. Is low-energy-ion bombardment generated X-ray emission a secondary mutational source to ion-beam-induced genetic mutation?

    Energy Technology Data Exchange (ETDEWEB)

    Thongkumkoon, P. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand); Prakrajang, K. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Faculty of Science, Maejo University, Chiang Mai 50290 (Thailand); Thopan, P.; Yaopromsiri, C. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Suwannakachorn, D. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand); Yu, L.D., E-mail: yuld@fnrf.science.cmu.ac.th [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand)

    2013-07-15

    Highlights: ► Detected X-ray emission from metal, plastic and biological samples. ► Characteristic X-ray emission was detected from metal but not from non-metals. ► Low-energy ion bombarded bacteria held in different sample holders. ► Bacteria held in metal holder had higher mutation rate than in plastic holder. ► Ion-beam-induced X-ray from biological sample is not a basic mutation source. -- Abstract: Low-energy ion beam biotechnology has achieved tremendous successes in inducing crop mutation and gene transfer. However, mechanisms involved in the related processes are not yet well understood. In ion-beam-induced mutation, ion-bombardment-produced X-ray has been proposed to be one of the secondary mutation sources, but the speculation has not yet been experimentally tested. We carried out this investigation to test whether the low-energy ion-beam-produced X-ray was a source of ion-beam-induced mutation. In the investigation, X-ray emission from 29-keV nitrogen- or argon- ion beam bombarded bacterial Escherichia coli (E. coli) cells held in a metal or plastic sample holder was in situ detected using a highly sensitive X-ray detector. The ion beam bombarded bacterial cells held in different material holders were observed for mutation induction. The results led to a conclusion that secondary X-ray emitted from ion-beam-bombarded biological living materials themselves was not a, or at least a negligible, mutational source, but the ion-beam-induced X-ray emission from the metal that made the sample holder could be a source of mutation.

  16. Is low-energy-ion bombardment generated X-ray emission a secondary mutational source to ion-beam-induced genetic mutation?

    International Nuclear Information System (INIS)

    Thongkumkoon, P.; Prakrajang, K.; Thopan, P.; Yaopromsiri, C.; Suwannakachorn, D.; Yu, L.D.

    2013-01-01

    Highlights: ► Detected X-ray emission from metal, plastic and biological samples. ► Characteristic X-ray emission was detected from metal but not from non-metals. ► Low-energy ion bombarded bacteria held in different sample holders. ► Bacteria held in metal holder had higher mutation rate than in plastic holder. ► Ion-beam-induced X-ray from biological sample is not a basic mutation source. -- Abstract: Low-energy ion beam biotechnology has achieved tremendous successes in inducing crop mutation and gene transfer. However, mechanisms involved in the related processes are not yet well understood. In ion-beam-induced mutation, ion-bombardment-produced X-ray has been proposed to be one of the secondary mutation sources, but the speculation has not yet been experimentally tested. We carried out this investigation to test whether the low-energy ion-beam-produced X-ray was a source of ion-beam-induced mutation. In the investigation, X-ray emission from 29-keV nitrogen- or argon- ion beam bombarded bacterial Escherichia coli (E. coli) cells held in a metal or plastic sample holder was in situ detected using a highly sensitive X-ray detector. The ion beam bombarded bacterial cells held in different material holders were observed for mutation induction. The results led to a conclusion that secondary X-ray emitted from ion-beam-bombarded biological living materials themselves was not a, or at least a negligible, mutational source, but the ion-beam-induced X-ray emission from the metal that made the sample holder could be a source of mutation

  17. Induced mutations in chickpea (Cicer arietinum L.) II. frequency and spectrum of chlorophyll mutations

    International Nuclear Information System (INIS)

    Kharkwal, M.C.

    1998-01-01

    A comparative study of frequency and spectrum of chlorophyll mutations induced by two physical (gamma rays, fast neutrons) and two chemical mutagens (NMU, EMS) in relation to the effects in M1 plants and induction of mutations in M2 was made in four chickpea (Cicer arietinum L.) varieties, two desi (G 130 & H 214) one Kabuli (C 104) and one green seeded (L 345). The treatments included three doses each of gamma rays (400, 500 & 600 Gy) and fast neutrons (5, 10 & 15 Gy) and two concentrations with two different durations of two chemical mutagens, NMU [0.01% (20h), & 0.02% (8h)] and EMS [0.1% (20h) & 0.2% (8h)]. The frequencies and spectrum of three different kinds of induced chlorophyll mutations in the order albina (43.5%), chlorina (27.3%) and xantha (24.2%) were recorded. Chemical mutagens were found to be efficient in inducing chlorophyll mutations in chickpea. Highest frequency of mutations was observed in green seeded var. L 345 (83% of M1 families and 19.9/1000 M2 plants). Kabuli var. C 104 was least responsive for chlorophyll mutations

  18. Advances and prospects for induced mutation breeding in Helongjiang Province

    International Nuclear Information System (INIS)

    Sun Guangzu

    1995-12-01

    Induced mutation breeding employed on soybean, spring wheat, maize, millet, fiber flax, chinese cabbage, kidney been and garlic in Heilongjiang province. Thirty-six new varieties had introduced and released from 1980 to 1994, made up 20.6% of total released varieties for the same period, accumulated cultivated area of 3.746 million hm 2 , and increased the income of formers to US dollar 168 million; 72 mutants having specific and utilizing values and traits have also been bred in the province. Basic research such as radiation breeding in combination with distant hybridization, biotechnology, and application new induced factors, improving selection methods, have been achieved; 91 articles have been published. These researches play an important role for increasing induced mutation breeding. Three items of suggestion to develop induced mutation breeding are made. (1 tab.)

  19. Base substitutions, frameshifts, and small deletions constitute ionizing radiation-induced point mutations in mammalian cells

    International Nuclear Information System (INIS)

    Grosovsky, A.J.; de Boer, J.G.; de Jong, P.J.; Drobetsky, E.A.; Glickman, B.W.

    1988-01-01

    The relative role of point mutations and large genomic rearrangements in ionizing radiation-induced mutagenesis has been an issue of long-standing interest. Recent studies using Southern blotting analysis permit the partitioning of ionizing radiation-induced mutagenesis in mammalian cells into detectable deletions and major genomic rearrangements and into point mutations. The molecular nature of these point mutations has been left unresolved; they may include base substitutions as well as small deletions, insertions, and frame-shifts below the level of resolution of Southern blotting analysis. In this investigation, we have characterized a collection of ionizing radiation-induced point mutations at the endogenous adenine phosphoribosyltransferase (aprt) locus of Chinese hamster ovary cells at the DNA sequence level. Base substitutions represented approximately equal to 2/3 of the point mutations analyzed. Although the collection of mutants is relatively small, every possible type of base substitution event has been recovered. These mutations are well distributed throughout the coding sequence with only one multiple occurrence. Small deletions represented the remainder of characterized mutants; no insertions have been observed. Sequence-directed mechanisms mediated by direct repeats could account for some of the observed deletions, while others appear to be directly attributable to radiation-induced strand breakage

  20. Alkylating agent (MNU)-induced mutation in space environment

    Science.gov (United States)

    Ohnishi, T.; Takahashi, A.; Ohnishi, K.; Takahashi, S.; Masukawa, M.; Sekikawa, K.; Amano, T.; Nakano, T.; Nagaoka, S.

    2001-01-01

    In recent years, some contradictory data about the effects of microgravity on radiation-induced biological responses in space experiments have been reported. We prepared a damaged template DNA produced with an alkylating agent (N-methyl-N-nitroso urea; MNU) to measure incorrect base-incorporation during DNA replication in microgravity. We examined whether mutation frequency is affected by microgravity during DNA replication for a DNA template damaged by an alkylating agent. Using an in vitro enzymatic reaction system, DNA synthesis by Taq polymerase or polymerase III was done during a US space shuttle mission (Discovery, STS-91). After the flight, DNA replication and mutation frequencies were measured. We found that there was almost no effect of microgravity on DNA replication and mutation frequency. It is suggested that microgravity might not affect at the stage of substrate incorporation in induced-mutation frequency.

  1. Mutation induced with ion beam irradiation in rose

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, H. E-mail: yhiroya@nias.affrc.go.jp; Nagatomi, S.; Morishita, T.; Degi, K.; Tanaka, A.; Shikazono, N.; Hase, Y

    2003-05-01

    The effects of mutation induction by ion beam irradiation on axillary buds in rose were investigated. Axillary buds were irradiated with carbon and helium ion beams, and the solid mutants emerged after irradiation by repeated cutting back. In helium ion irradiation, mutations were observed in plants derived from 9 buds among 56 irradiated buds in 'Orange Rosamini' and in plants derived from 10 buds among 61 irradiated buds in 'Red Minimo'. In carbon ion, mutations were observed in plants derived from 12 buds among 88 irradiated buds in 'Orange Rosamini'. Mutations were induced not only in higher doses but also in lower doses, with which physiological effect by irradiation was hardly observed. Irradiation with both ion beams induced mutants in the number of petals, in flower size, in flower shape and in flower color in each cultivar.

  2. Induced mutations in Petunia hybrida Hort

    International Nuclear Information System (INIS)

    Kashikar, S.G.; Khalatkar, A.S.

    1980-01-01

    The seeds of a white flowering strain of Petunia hybrida hort. were treated with different concentrations of ethyl methane-sulphonate, sodium azide, diethyl sulphate, N-methyl-N'-nitro-N-nitrosoguanidine, ethylene imine and gamma radiations. A large number of flower colour and morphological mutants superior to the parental variety were obtained. The flower colour mutations took the form of sectors and whole colour changes. The latter included a large spectrum of colours from light to deep magenta, pink, purple and violet coloured petals. The anthocyanin analysis of these mutants showed different patterns of pigments responsible for the various colours. In addition to these, a broad spectrum of morphological mutations of ornamental value included dwarfs, unbranched, cristata, densa, campyloflora and velutiniflora types. The inheritance of horticulturally important characters was investigated in M 3 and M 4 generations. (author)

  3. Genetic improvement of Sesamun indicum through induced mutations

    International Nuclear Information System (INIS)

    Rajput, M.A.; Khan, Z.H.; Jafri, K.A.; Fazal Ali, J.A.

    2001-01-01

    Pakistan is chronically deficient in the production of edible oils. To enhance local production of edible oils, a mutation breeding project entitled ''Genetic improvement of Sesamum indicum through induced mutations'' was initiated for developing high yielding and widely adapted varieties of sesame. Quite a few mutants having earliness, short stature, semi-indehiscence, compact plant type, heavy bearing and high seed yield have been developed. The true breeding mutant lines developed have exhibited impressive yield potential. (author)

  4. Genetic improvement of 'NPq' rice with induced mutations

    International Nuclear Information System (INIS)

    Ram, Mahabal

    1974-01-01

    Exposure of the seeds of rice to different doses of gamma-rays increased the total mutation frequency with an increase in the dose rate, and the most economic mutations occurred around 30 kr. Induced mutants with dwarf plant type, early maturity, fine grain, high-yielding ability, and resistance to lodging and major diseases were isolated in the M, and M generations. Genetical studies indicated that height is controlled by 4 pairs of additive genes, grass-clumps by 2 pairs of non-allelic interacting genes (inhibitory), and chlorophyll mutations such as albina by 2 pairs of duplicate genes and xantha by a single gene pair. (author)

  5. Mutations induced by ultraviolet radiation affecting virulence in Puccinia striiformis

    International Nuclear Information System (INIS)

    Shang Hongsheng; Jing Jinxue; Li Zhenqi

    1994-01-01

    Uredospores of parent culture, cy 29-1, were treated by ultraviolet radiation and mutations to virulent were tested on resistant wheat cultivars inoculated with treated spores. 7 mutant cultures virulent to the test cultivars were developed with estimated mutation rate 10~6~10~4. The virulence of mutant cultures was different from the all known races of stripe rust. Resistance segregation to mutant cultures was detected in two test cultivars. The results suggested that mutation was important mechanism of virulence variation operative in asexual population of rust fungi

  6. Validation of an NGS mutation detection panel for melanoma.

    Science.gov (United States)

    Reiman, Anne; Kikuchi, Hugh; Scocchia, Daniela; Smith, Peter; Tsang, Yee Wah; Snead, David; Cree, Ian A

    2017-02-22

    Knowledge of the genotype of melanoma is important to guide patient management. Identification of mutations in BRAF and c-KIT lead directly to targeted treatment, but it is also helpful to know if there are driver oncogene mutations in NRAS, GNAQ or GNA11 as these patients may benefit from alternative strategies such as immunotherapy. While polymerase chain reaction (PCR) methods are often used to detect BRAF mutations, next generation sequencing (NGS) is able to determine all of the necessary information on several genes at once, with potential advantages in turnaround time. We describe here an Ampliseq hotspot panel for melanoma for use with the IonTorrent Personal Genome Machine (PGM) which covers the mutations currently of most clinical interest. We have validated this in 151 cases of skin and uveal melanoma from our files, and correlated the data with PCR based assessment of BRAF status. There was excellent agreement, with few discrepancies, though NGS does have greater coverage and picks up some mutations that would be missed by PCR. However, these are often rare and of unknown significance for treatment. PCR methods are rapid, less time-consuming and less expensive than NGS, and could be used as triage for patients requiring more extensive diagnostic workup. The NGS panel described here is suitable for clinical use with formalin-fixed paraffin-embedded (FFPE) samples.

  7. New cultivars of jujube induced by mutation

    International Nuclear Information System (INIS)

    Hoang, V.T.; Tuynh, N.V.

    1989-01-01

    Full text: Mutation breeding of jujube (Ziziphus mauritiana Lin.) received attention by the Food Crops Research Institute since 1978. Mutations can be directly released as new cultivars or indirectly as bud grafting source. N-methyl-N-nitroso urea (MNH) was used at a concentration of 0.02-0.04% for 12 h treatment of pre-germinated seeds of different jujube cultivars. Some useful mutants were selected and directly released as new cultivars to farmers. Of the selected mutants two cultivars, ''Ma hong'' and ''Dao tien'', are the most preferable and popularly grown in the country. ''Ma hong'' is a mutant of ''Gia Loc'', a very popular cultivar. Main useful traits of ''Gia Loc'' such as early maturing, two crops of fruits per year are maintained (harvest in December and August). ''Ma hong'' has round-formed, pink rose coloured, sweeter fruits and stable fruit yield in off-season (Aug.) as compared with oval-formed, yellow-coloured and sour fruit of ''Gia Loc''. ''Dao tien'' is a mutant of the local variety ''Thien Phien'' with quite different traits. The original cultivar is late maturing (harvested in Feb.) with one crop of fruit per year and has small fruits (mean wt. of fruit at harvest 20 g). ''Dao tien'' is one month earlier in maturing allowing two crops of fruit per year (harvested in Jan. and Nov.). Fruits are round-formed, bigger (mean wt. of fruit: 25 g) and more tasteful (peach-flavored and brittle). (author)

  8. Biological effects of space-induced mutation on robinia pseudoacacia

    International Nuclear Information System (INIS)

    Yuan Cunquan; Li Yun; Lu Chao; Yang Min; Zhang Yuyao

    2010-01-01

    Dry seeds of Robinia pseudoacacia were carried by Shijian No.8 breeding satellite for mutagenesis and the biological effect of space-induced mutation was studied. The parameters of Robinia pseudoacacia such as plant height, stem base, branch number, knot spacing, length of thorn and chlorophyll content were analyzed, and, at the same time, the genetic diversity was tested by SSR marker. The results showed that the plant height and stem base of 2-year-old seedlings which derived from space mutagenesis were 22.0% and 24.1% lower than those of control, and 3-year-old seedlings were 13.1% and 22.4% lower than those of control, respectively. While the inhibiting effect of plant height became undermined in the following growth years. However, the inhibiting effect in stem base existed all the time,the length of thorn of branch and stem were 15.6% and 28.6% shorter than the control,respectively. Compared with the control,the variation of the length of thorn from stem was extremely significant. The variation of chlorophyll a content from space mutagenesis compared with control was not remarkable, while the total chlorophyll and chlorophyll b contents were 18.7% and 9.7% lower than those of control, respectively, and the difference between space mutagenesis and control was significant. While the chlorophyll a/b was 25.6% higher than that of control, but the difference was not significant. The coefficient of variation of the relative traits was increased by the space mutagenesis. The extensively population genome mutation after space-induction were not detected by SSR (Simple Sequence Repeats). (authors)

  9. Induced mutation to monocotyledony in periwinkle, Catharanthus ...

    Indian Academy of Sciences (India)

    Unknown

    (i) insufficiency in endogenous kinetin may lead to monocotyledonous embryo patterning and (ii) dicotyledonous em- ... Induced-mutagenesis experiments in plants have so far .... C. roseus is a small perennial herb of family Apocyna-.

  10. Gamma Radiation-Induced Mutations in Soybeans

    International Nuclear Information System (INIS)

    Smutkupt, S.

    1998-01-01

    The main objective of soybean radiation experiments was to create genetic variability in soybeans of various cultivars, mutants and mutation-derived lines with the aim of producing superior breeding lines with resistance to soybean rust (Phakopsora pachyhrizi Syd.) It took altogether 12 generations over six years after gamma irradiation if soybean seeds to produce the best resistant line (81-1-038) which a variety could be developed from it. This Line 81-1-038 showed a very good specific resistance to soybean rust, Thai race 2 and moderately resistance to Thai race 1. In the rainy season of 1985, Line 81-1-038 out yielded S.J.4 (a mother line) by 868 kg/ha in a yield trail at Suwan Farm, Pak Chong, Nakorn Rajchasima. This soybean rust mutant was later named D oi Kham

  11. Chloroplast mutations induced by 9-aminoacridine hydrochloride are independent of the plastome mutator in Oenothera.

    Science.gov (United States)

    GuhaMajumdar, M; Baldwin, S; Sears, B B

    2004-02-01

    Oenothera plants homozygous for the recessive plastome mutator allele ( pm) show chloroplast DNA (cpDNA) mutation frequencies that are about 1,000-fold higher than spontaneous levels. The pm-encoded gene product has been hypothesized to have a function in cpDNA replication, repair and/or mutation avoidance. Previous chemical mutagenesis experiments with the alkylating agent nitroso-methyl urea (NMU) showed a synergistic effect of NMU on the induction of mutations in the pm line, suggesting an interaction between the pm-encoded gene product and one of the repair systems that corrects alkylation damage. The goal of the experiments described here was to examine whether the pm activity extends to the repair of damage caused by non-alkylating mutagens. To this end, the intercalating mutagen, 9-aminoacridine hydrochloride (9AA) was tested for synergism with the plastome mutator. A statistical analysis of the data reported here indicates that the pm-encoded gene product is not involved in the repair of the 9AA-induced mutations. However, the recovery of chlorotic sectors in plants derived from the mutagenized seeds shows that 9AA can act as a mutagen of the chloroplast genome.

  12. Induced mutations for resistance to leaf rust in wheat

    International Nuclear Information System (INIS)

    Borojevic, K.

    1983-01-01

    Problems related to the induction of mutations for disease resistance were investigated under several aspects, using the wheat/leaf rust system. Previously selected mutant lines, tested in M 11 and M 13 , were found to differ with regard to infection type and disease severity from the original varieties. To verify the induced-mutation origin, these mutants were examined further using test crosses with carriers of known genes for leaf rust resistance and electrophoresis. A separate experiment to induce mutations for leaf rust resistance in the wheat varieties Sava, Aurora and Siete Cerros, using gamma rays, fast neutrons and EMS, yielded mutants with different disease reaction in the varieties Sava and Aurora at a frequency of about 1x10 - 3 per M 1 plant progenies. (author)

  13. Use of gamma radiation in floriculture industry for development of new varieties through induced mutation

    International Nuclear Information System (INIS)

    Datta, S.K.

    2002-01-01

    Nuclear radiation (gamma rays) can create changes in genetic make up of plant material through mutation. Gamma ray induced mutation is now an established method for crop improvement. It is well known that the crops which are propagated vegetatively are very suitable for the application of mutation breeding methods. In floriculture industry there is always demand and necessity of new and novel ornamental varieties. Flower colour and shape are the most important components of novelties. Gamma rays have been most successfully use to produce quite a large number of new promising,varieties in different ornamental (Bougainvillea - 4, Perennial portulaca-6, Chrysanthemum-43, Hibiscus-1, Rose-16, Tuberose-2, Lantana depressa-3 etc.) plants by bringing about genetic changes at Floriculture Section, National Botanical Research. Institute, Lucknow, India. Research carried out covers radiosensitivity, selection of materials, methods of exposure to gamma rays, suitable dose of gamma rays, detection of mutants, isolation of mutants and commercial exploitation of mutants. A good number of mutant varieties have been well accepted in the floriculture industry. The mutant varieties are with new flower colour and shape. More than three decades of applied mutation breeding work has now established beyond doubt that mutation breeding will constitute an excellent supplement to the conventional methods for development of new varieties . Detection of somatic, mutations in flower colour/shape in different vegetative generations (M 1 V 1 , M 1 V 2 , M 1 V 3 and even in later vegetative generations), mutation frequency and spectrum relationship with dose of gamma radiation have been precisely determined. Studies have clearly proved that mutation breeding technique can be exploited for the creation of new and novel ornamental cultivars of commercial importance by inducing genetic variation in already adapted, modern genotypes and can also enrich the germplasm of ornamental horticulture

  14. 21 CFR 864.7280 - Factor V Leiden DNA mutation detection systems.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Factor V Leiden DNA mutation detection systems....7280 Factor V Leiden DNA mutation detection systems. (a) Identification. Factor V Leiden deoxyribonucleic acid (DNA) mutation detection systems are devices that consist of different reagents and...

  15. Feeding the world with induced mutations and biotechnology

    International Nuclear Information System (INIS)

    Mohan Jain, S.

    2002-01-01

    The paper discussed the following subjects: biotechnology - somaclonal variation, somatic embryogenesis, somatic cell hybridization; induced mutations - in banana, ornamental plants; in vitro mutagenesis; T-DNA insertional mutagenesis. Suggestions for improving biotechnology in the developing countries also presented in the paper

  16. Induced mutations of rust resistance genes in wheat

    International Nuclear Information System (INIS)

    McIntosh, R.A.

    1983-01-01

    Induced mutations are being used as a tool to study genes for resistance in wheat. It was found that Pm1 can be separated from Lr20 and Sr15, but these two react like a single pleiotropic gene. Mutants were further examined in crosses and backmutations have been attempted. (author)

  17. A radiation-induced compact type Granny Smith apple mutation

    International Nuclear Information System (INIS)

    Hurter, N.; Van Tonder, M.J.

    1982-01-01

    More successful compact mutant clones of Granny Smith apple are being sought, for those that have so far arisen naturally have undesirable tree and fruit charateristics. For this purpose, gamma rays from a Cobalt-60 radiation unit were used to induce mutant types artificially. One compact mutation of Granny Smith was produced via re-irradiation

  18. Cellular repair and its importance for UV-induced mutations

    Energy Technology Data Exchange (ETDEWEB)

    Slamenova, D [Slovenska Akademia Vied, Bratislava (Czechoslovakia). Vyskumny Ustav Onkologicky

    1975-01-01

    Current knowledge is briefly surveyed of the mechanism of the biological repair of injuries induced in DNA cells by the action of various factors, mainly ultraviolet radiation. Genetic loci determining the sensitivity of cells to UV radiation are defined and principal reparation processes are explained; excision repair is described more fully. The role of biological repair is discussed in view of UV-induced mutations in DNA cells.

  19. Induced mutation in the improvement of beans

    International Nuclear Information System (INIS)

    Avila, R.L.; Murty, B.R.

    1984-01-01

    A program on mutational rectification was undertaken in 1978 utilizing gamma radiation, as seed treatment for three local cultivars of compea, Vigna unguiculata plus one cultivar of mungbean, Vigna radiata. The selection criteria were compact plant type with determinate habit, early maturity, resistance to Macrophomina and high yield. The selected material now in M 7 generation, selection being made in M 2 for plant type. In subsequent generations selections were made for resistance to Macrophomina, stability of plant type, uniform pod filling, seed size, good nodulation, synchronous flowering and productivity under close spacing conditions. Simultaneous studies on root development were made at seedling stage. In mungbean, emphasis on non-shattering was made. Finally 12 mutants were selected in M 5 , with uniformity for the cited characters and higher yields than the parental material, ranging from 20 to 110% superior yield in some mutants and sowing dates. Multilocation trials are being conducted to test the wide adaptability of these mutants. Chemical mutagenesis using sodium azide with and without gamma radiation was also used. From these trials nonnodulating mutants were recovered. These materials are being multiplied to be used in basic studies of the Rhizobium - legume symbiosis. Ecophysiological studies of the promising mutants have been carried out under different sowing dates at 45 day intervals. These results are of wide interest in studies of tropical adaptation of grain legumes, on which very few reports are available so far. These results are discussed with particular reference to yield and its stability for the cropping system in Venezuela. (author)

  20. Induced mutations in mungbean- variety BM-4

    International Nuclear Information System (INIS)

    Chavan, A.A.; Patil, V.D.; Pawar, R.B.

    2000-01-01

    Mung bean (Vigna radiata) is an important crop. Marathwada Agricultural University has developed and released a variety BM4 for Western Zone. This variety has got yield potential of 1200-1300 kg/ha. However it has small grain size and dull green colour resulting in less dahl recovery and less market price. To improve these parameters, a mutation breeding programme was taken up. Dry seeds of variety BM4 were treated with 10, 15, 25 kR gamma rays at BARC Mumbai. In M 1 generation, germination decreased with increased dose of gamma rays. Twenty five kR showed lowest germination, 10 and 15 kR showed satisfactory germination. Individual plants were harvested and plant to row progenies were grown in M 2 in augmented block design. Range of mean was 39.8 to 77.2, 6.3 to 45.4, 1.85 to 3.25 and 9.2 to 60.0 for plant height (cm), number of pods/plant, test weight (g) and yield/plant(g) respectively. Out of 3 doses of gamma rays 10 kR proved more effective in increasing seed size, number of pods and seed yield/plant. (author)

  1. Sucrose and IQ induced mutations in rat colon by independent

    DEFF Research Database (Denmark)

    Hansen, Max; Hald, M. T.; Autrup, H.

    2004-01-01

    Sucrose-rich diets have repeatedly been observed to have co-carcinogenic actions in colon and liver of rats and to increase the number of 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) induced aberrant crypt foci in rat colon. To investigate a possible interaction between sucrose and IQ...... on the genotoxicity in rat liver and colon, we gave Big Blue rats(TM) a diet containing sucrose (0%, 3.45% or 13.4% w/w) and/or IQ (70 ppm) for a period of 3 weeks. Sucrose and IQ increased the mutation frequency in the colon. The effect of combined treatments with IQ and sucrose on the mutation frequencies...... was additive indicating that sucrose and IQ act independently. This was supported by the mutation spectra where sucrose expands the background mutations in the colon, whereas IQ, in other studies, more specifically has induced G:C --> T:A transversions. In the liver IQ increased the mutation frequency, whereas...

  2. Specific gene mutations induced by heavy ions

    International Nuclear Information System (INIS)

    Freeling, M.; Karoly, C.W.; Cheng, D.S.K.

    1980-01-01

    This report summarizes our heavy-ion research rationale, progress, and plans for the near future. The major project involves selecting a group of maize Adh1 mutants induced by heavy ions and correlating their altered behavior with altered DNA nucleotide sequences and sequence arrangements. This research requires merging the techniques of classical genetics and recombinant DNA technology. Our secondary projects involve (1) the use of the Adh gene in the fruit fly, Drosophila melanogaster, as a second system with which to quantify the sort of specific gene mutants induced by heavy ions as compared to x rays, and (2) the development of a maize Adh1 pollen in situ monitor for environmental mutagens

  3. Timing of the uv mutagenesis in yeast: a pedigree analysis of induced recessive mutation

    International Nuclear Information System (INIS)

    James, A.P.; Kilbey, B.J.

    1977-01-01

    The mechanism of uv-induced mutation in eukaryotes was studied in individual yeast cells by a procedure that combined pedigree analysis and tetrad analysis. The technique involved the induction of recessive lethals and semilethals in G1 diploid cells. Induced frequencies were 25 and 61% at survival levels of 90 and 77%, respectively. No evidence of gross chromosome aberrations was detected. Recessive mutations that affect only one strand or that affect both strands of the DNA molecule are induced much at random among a population of cells, and both types can occur within the same cell. However, the data confirm that two-strand mutations are in the majority after a low level of irradiation. The simplest explanation involves a mechanism whereby most mutations are fixed in both strands prior to the first round of post-irradiation DNA replication. The recessive mutational consequences of irradiation are exhausted at the conclusion of the first post-irradiation cell division, although dominant-lethal sectoring continues at a high level through the second post-irradiation division. It is concluded that pyrimidine dimers that persist to the second round of DNA replication are rare or ineffective

  4. The timing of UV mutagenesis in yeast: a pedigree analysis of induced recessive mutation.

    Science.gov (United States)

    James, A P; Kilbey, B J

    1977-10-01

    The mechanism of UV-induced mutation in eukaryotes was studied in individual yeast cells by a procedure that combined pedigree analysis and tetrad analysis. The technique involved the induction of recessive lethals and semilethals in G1 diploid cells. Induced frequencies were 25 and 61 percent at survival levels of 90 and 77 percent, respectively. No evidence of gross chromosome aberrations was detected. Recessive mutations that affect only one strand or that affect both strands of the DNA molecule are induced much at random among a population of cells, and both types can occur within the same cell. However, the data confirm that two-strand mutations are in the majority after a low level of irradiation. The simplest explanation involves a mechanism whereby most mutations are fixed in both strands prior to the first round of post-irradiation DNA replication. The recessive mutational consequences of irradiation are exhausted at the conclusion of the first post-irradiation cell division, although dominant-lethal sectoring continues at a high level through the second post-irradiation division. It is concluded that pyrimidine dimers that persist to the second round of DNA replication are rare or ineffective.

  5. UV-induced tandem double mutations in the trpA gene of E. coli

    International Nuclear Information System (INIS)

    Piechocki, R.; Langhammer, R.

    1980-01-01

    The ultraviolet light induction of tandem double mutations in a reverse mutation system was shown using trpA mutants which are characterized by the codon sequences GAA and AAG in codon position 211. Among 597 Trp + independent revertants of the trpA (AAG211) strain 3 full revertants were detected arising from UV-induced tandem double base exchanges. In the codon unit 211 full revertants due to single base exchanges are at least 20 times as frequent as full revertants due to tandem double base exchanges. (author)

  6. DHPLC technology for high-throughput detection of mutations in a durum wheat TILLING population.

    Science.gov (United States)

    Colasuonno, Pasqualina; Incerti, Ornella; Lozito, Maria Luisa; Simeone, Rosanna; Gadaleta, Agata; Blanco, Antonio

    2016-02-17

    Durum wheat (Triticum turgidum L.) is a cereal crop widely grown in the Mediterranean regions; the amber grain is mainly used for the production of pasta, couscous and typical breads. Single nucleotide polymorphism (SNP) detection technologies and high-throughput mutation induction represent a new challenge in wheat breeding to identify allelic variation in large populations. The TILLING strategy makes use of traditional chemical mutagenesis followed by screening for single base mismatches to identify novel mutant loci. Although TILLING has been combined to several sensitive pre-screening methods for SNP analysis, most rely on expensive equipment. Recently, a new low cost and time saving DHPLC protocol has been used in molecular human diagnostic to detect unknown mutations. In this work, we developed a new durum wheat TILLING population (cv. Marco Aurelio) using 0.70-0.85% ethyl methane sulfonate (EMS). To investigate the efficiency of the mutagenic treatments, a pilot screening was carried out on 1,140 mutant lines focusing on two target genes (Lycopene epsilon-cyclase, ε-LCY, and Lycopene beta-cyclase, β-LCY) involved in carotenoid metabolism in wheat grains. We simplify the heteroduplex detection by two low cost methods: the enzymatic cleavage (CelI)/agarose gel technique and the denaturing high-performance liquid chromatography (DHPLC). The CelI/agarose gel approach allowed us to identify 31 mutations, whereas the DHPLC procedure detected a total of 46 mutations for both genes. All detected mutations were confirmed by direct sequencing. The estimated overall mutation frequency for the pilot assay by the DHPLC methodology resulted to be of 1/77 kb, representing a high probability to detect interesting mutations in the target genes. We demonstrated the applicability and efficiency of a new strategy for the detection of induced variability. We produced and characterized a new durum wheat TILLING population useful for a better understanding of key gene functions

  7. Improvement of rice through induced mutations

    International Nuclear Information System (INIS)

    Miah, A.J.; Mansur, M.A.; Jalal Uddin, M.

    1981-01-01

    In a field trial conducted in randomized blocks with 4 replications during November to April 1977-78, 4 radiation-induced mutants of rice (Oryza sativa Linn.) were found to be 23 to 41 days earlier than 'IR 8'. 'Mut 1-2' gave the highest grain yield (2,884 kg/ha), followed by 'Mut 1-1' (2, 183 kg/ha) and 'BR 3' (1,825 kg/ha). Though all the mutant lines were suceptible to bacterial leaf-blight in greenhouse, in the field 'Mut 1-2' was moderately resistant and 'Mut 1-1' moderately susceptible. (auth.)

  8. Induced marker gene mutations in soybean

    International Nuclear Information System (INIS)

    Sawada, S.; Palmer, R.G.

    1989-01-01

    Full text: Non-fluorescent root mutants in soybean are useful as markers in genetic studies. 13 such mutants were detected among more than 150 000 seedlings derived from soybean lines treated with 6 mutagens. One of them, derived from variety 'Williams' treated with 20 kR gamma rays, did not correspond to the already known spontaneous non-fluorescent mutants. It was assigned the identification no. T285 and the gene symbol fr5. The other mutants corresponded with known loci fr1, fr2 or fr4. (author)

  9. Mutations induced by the action of metal ions in Pisum

    Energy Technology Data Exchange (ETDEWEB)

    von Rosen, G

    1957-01-01

    Simple metal ions may induce both radiomimetic effects and genuine gene mutations of the same type which occurs from ionizing radiation and from treatment with some chemical agencies as e.g., mustard gas. The main material during the experiments has been species of Pisum. The biochemical principle which lies behind these reactions is the complex-forming ability among those reactive bivalent metal elements. The author assumes that interruptions of the chelate formation in the cell synthesis form the real background to the observed activity of the metal ions. The possible role in the evolution of the plant- and animal kingdom and the probable value for plant-breeding of the mutation activity observed are suggested. A new field for mutation experiments may here be opened and the results must hitherto be judged as interesting and promising. 13 references, 7 figures, 4 tables.

  10. Induced mutations and marker assisted breeding in soybean

    Energy Technology Data Exchange (ETDEWEB)

    Chotechuen, Somsong [Prachinburi Rice Research Center, Prachinburi (Thailand); Srisombun, Somsak [Department of Agriculture, Field Crops Research Institute, Bangkok (Thailand); Lamseejan, Siranut [Kasetsart Univ., Department of Applied Radiation and Isotopes, Bangkok (Thailand)

    2002-02-01

    Soybean is one of the important crops in Thailand. Constraints to soybean production include low yield potential, susceptibility to diseases and insects, and non-adoption of appropriate management practices. Mutation induction has been used to improve soybean yield and resistance to major diseases such as rust, purple seed, crinkle leaf, anthracnose and green seed. This paper reviews previous work and achievements of induced mutations in soybean. Successful examples are the release of a soybean variety, Doi Kham, and the development of a mutant CM 60-10kr-71; both are resistant to rust disease. The paper also gives example of the use of soybean SSR markers to identify QTL associated with pod shattering, and emphasizes the integration of mutation techniques and marker assisted selection for soybean improvement. (author)

  11. Induced mutation altering flower colour in Chrysanthemum

    Energy Technology Data Exchange (ETDEWEB)

    Datta, S K [National Botanical Research Institute, Lucknow (India)

    1989-01-01

    Full text: 'Flirt' is a double Korean type, small flowered Chrysanthemum of red colour. Rooted cuttings were treated with 1.5-2.5 krad gamma rays. A chimeral flower colour mutant was detected after 1.5 krad treatment. After purification through repeated cuttings a mutant clone was developed and released as commercial cultivar 'Man Bhawan'. It produces bi-coloured flower-heads: yellow and red at full bloom stage becoming completely yellow later on. By chromatography, 6 pigment spots could be identified in the variety 'Flirt' but only 5 in the mutant, violet (hRf 69.83) being absent. Spectrophotometric analysis of petal extracts showed presence of three peaks in both 'Flirt' and 'Man Bhawan' at full bloom stage but only two in 'Man Bhawan' at fading stage. (author)

  12. Ultrarapid mutation detection by multiplex, solid-phase chemical cleavage

    Energy Technology Data Exchange (ETDEWEB)

    Rowley, G.; Saad, S.; Giannelli, F.; Green, P.M. [Guy`s & St. Thomas`s Hospitals, London (United Kingdom)

    1995-12-10

    The chemical cleavage of mismatches in heteroduplexes formed by probe and test DNA detects and locates any sequence change in long DNA segments ({approximately}1.8 kb), and its efficiency has been well tested in the analysis of both average (e.g., coagulation factor IX) and large, complex genes (e.g., coagulation factor VIII and dystrophin). In the latter application RT/PCR products allow the examination of all essential sequences of the gene in a minimum number of reactions. We use two specific chemical reactants (hydroxylamine and osmium tetroxide) and piperidine cleavage of the above procedure to develop a very fast mutation screening method. This is based on: (1) 5{prime} or internal fluorescent labeling to allow concurrent screening of three to four DNA fragments and (2) solid-phase chemistry to use a microliter format and reduce the time required for the procedure, from amplification of sequence to gel loading inclusive, to one person-working-day. We test the two variations of the method, one entailing 5{prime} labeling of probe DNA and the other uniform labeling of both probe and target DNA, by detecting 114 known hemophilia B (coagulation factor IX) mutations and by analyzing 129 new patients. Uniform labeling of both probe and target DNA prior to formation of the heteroduplexes leads to almost twofold redundancy in the ability to detect mutations. Alternatively, the latter procedure may offer very efficient though less than 100% screening for sequence changes with only hydroxylamine. The full method with two chemical reactions (hydroxylamine and osmium tetroxide) should allow one person to screen with virtually 100% accuracy more than 300 kb of sequence in three ABI 373 gels in 1 day. 26 refs., 7 figs., 1 tab.

  13. Use of induced mutations for cotton breeding in India

    International Nuclear Information System (INIS)

    Raut, R.N.

    1980-01-01

    A large number of studies have been reported in recent years on the use of induced mutations in the improvement of food crops and ornamentals. Similar investigations on fibre crops like cotton have, however, been relatively few. The fact that most of the economically useful characters in cotton are under polygenic control appears to be the main limiting factor. Inspite of this there are reports of radiation induced useful mutations used as commercial varieties. As early as 1950 a X-ray induced mutant variety of G. hirsutum cotton Indore-2 was released for commercial cultivation in Madhya Pradesh and covered more than one lac hectares. More recently an early maturing mutant variety MCU-7 was released for cultivation in summer rice fallows of Tamil Nadu and covers nearly 10,000 acres. Other promising mutant strains found suitable b.v large scale trials and recommended for cultivation under specific conditions are Okra leaf mutant, photoinsensitive mutant of MCU-5 (named Rasmi) and Jassid tolerant early maturing mutant 4-1 (Pusa Ageti). In addition improved varieties like Badnaawar-1, Khandwa-2 and M64 have been evolved by utilizing mutant lines in cross breeding. The scope of induced mutation method as a breeding technique for cotton improvement in India is very wide. (author)

  14. Automation of diagnostic genetic testing: mutation detection by cyclic minisequencing.

    Science.gov (United States)

    Alagrund, Katariina; Orpana, Arto K

    2014-01-01

    The rising role of nucleic acid testing in clinical decision making is creating a need for efficient and automated diagnostic nucleic acid test platforms. Clinical use of nucleic acid testing sets demands for shorter turnaround times (TATs), lower production costs and robust, reliable methods that can easily adopt new test panels and is able to run rare tests in random access principle. Here we present a novel home-brew laboratory automation platform for diagnostic mutation testing. This platform is based on the cyclic minisequecing (cMS) and two color near-infrared (NIR) detection. Pipetting is automated using Tecan Freedom EVO pipetting robots and all assays are performed in 384-well micro plate format. The automation platform includes a data processing system, controlling all procedures, and automated patient result reporting to the hospital information system. We have found automated cMS a reliable, inexpensive and robust method for nucleic acid testing for a wide variety of diagnostic tests. The platform is currently in clinical use for over 80 mutations or polymorphisms. Additionally to tests performed from blood samples, the system performs also epigenetic test for the methylation of the MGMT gene promoter, and companion diagnostic tests for analysis of KRAS and BRAF gene mutations from formalin fixed and paraffin embedded tumor samples. Automation of genetic test reporting is found reliable and efficient decreasing the work load of academic personnel.

  15. Radiation induced mutations for breeding of sorghum

    Energy Technology Data Exchange (ETDEWEB)

    Bretaudeau, A [Rural Polytechnic Inst., Katibougou, Koulikoro (Mali)

    1997-07-01

    Several sorghum cultivars of Mali were irradiated with different doses of gamma rays and compared with the Caudatum types. Radio-sensitivity studies suggested that the local types were less sensitive to radiation than the introduced types. Whereas the local varieties survived dose of 300 Gy, in Caudatum types, seed germination and growth were significantly reduced at 200 Gy. Several agronomically important mutants were obtained among the progeny of the local types. Some of the mutants were shorter and had improved panicle characteristics. Radiation-induced variation was observed in several characters such as plant height, resistance to lodging, plant architecture, drought tolerance, panicle length and compactness, seed size and color, seed quality (viterous or floury) and protein content, glume color and structure, flowering data (early and late maturity), and tillering capacity. One mutant was drought tolerant. Promising mutants were selected and are presently under evaluation in the National List Trials to confirm their potential and future release. Selected variants have been also crossed with local types to obtain promising material. (author). 8 refs, 2 tabs.

  16. Radiation induced mutations for breeding of sorghum

    International Nuclear Information System (INIS)

    Bretaudeau, A.

    1997-01-01

    Several sorghum cultivars of Mali were irradiated with different doses of gamma rays and compared with the Caudatum types. Radio-sensitivity studies suggested that the local types were less sensitive to radiation than the introduced types. Whereas the local varieties survived dose of 300 Gy, in Caudatum types, seed germination and growth were significantly reduced at 200 Gy. Several agronomically important mutants were obtained among the progeny of the local types. Some of the mutants were shorter and had improved panicle characteristics. Radiation-induced variation was observed in several characters such as plant height, resistance to lodging, plant architecture, drought tolerance, panicle length and compactness, seed size and color, seed quality (viterous or floury) and protein content, glume color and structure, flowering data (early and late maturity), and tillering capacity. One mutant was drought tolerant. Promising mutants were selected and are presently under evaluation in the National List Trials to confirm their potential and future release. Selected variants have been also crossed with local types to obtain promising material. (author). 8 refs, 2 tabs

  17. A parylene-based dual channel microelectrophoresis system for rapid mutation detection via heteroduplex analysis

    NARCIS (Netherlands)

    Sukas, S.; Erson, Ayse Elif; Sert, Cuneyt; Kulah, Haluk

    2008-01-01

    A new dual channel micro-electrophoresis system for rapid mutation detection based on heteroduplex analysis was designed and implemented. Mutation detection was successfully achieved in a total separation length of 250 μm in less than 3 min for a 590 bp DNA sample harboring a 3 bp mutation causing

  18. Genomic mutation study for long-term cells induced by carbon ions

    International Nuclear Information System (INIS)

    Wang, X.; Furusawa, Y.; Suzuki, M.; Hirayama, R.; Matsumoto, Y.; Qin, Y.

    2007-01-01

    Complete text of publication follows. Objective: Densely ionizing (high LET) radiation can increase the relative biological effectiveness of cell and tissue. Astronauts in the space exploration have the potential exposure of chronic low-dose radiations in the field of low-flux galactic cosmic rays (GCR) and the subsequent biological effects have become one of the major concerns of space science. Furthermore, Heavy ions also are used new radiation therapy owing increased lethal effectiveness of high LET radiation. During radiation therapy, normal tissues also are exposed to ionizing radiation. Radiation can induce genomic mutation and instability in descendants of irradiated cells. Induction of genomic instability can represent one of the initiating steps leading to malignant transformation. Higher frequencies of mutation can be expected to provide higher rates of carcinogenicity with human exposure. Therefore, the study of radiation induced genomic mutation and instability is relevant to the estimates of the risk of secondary malignancies associated with radiation therapy and the carcinogenic effects of space environmental radiation. The hypoxanthine-guanine phosphoribosyltransferase (hprt) locus has been the most commonly used as a target gene for mutation detection studies. In this study, we investigated the generation expression dependence of mutation induction on HPRT locus in CHO cells irradiated with carbon ions. Methods: Chinese hamster ovary (CHO) cells were irradiated with graded doses of carbon ions (290MeV/u, LET:13kev/um) accelerated with Heavy Ion Medical Accelerator in Chiba (HIMAC) at National Institute of Radiological Sciences(NIRS). The survival effect of cells plated immediately after irradiation was measured with cell colony formation assay. After irradiation, cells were continues reseeding and cultures for lone-term proliferation. Cell samples were collected at 6, 12, 18, 24, 30, 37 and 44 days post irradiation. Mutation induction of cell

  19. Suitability of two-dimensional electrophoretic protein separations for quantitative detection of mutations

    International Nuclear Information System (INIS)

    Taylor, J.; Anderson, N.L.; Anderson, N.G.; Gemmell, A.; Giometti, C.S.; Nance, S.L.; Tollaksen, S.L.

    1986-01-01

    Separation of proteins by two-dimensional electrophoresis (2DE) provides a powerful method for mutagenesis studies, since hundreds of proteins can be monitored simultaneously. In previous mutation studies in which 2DE has been used, only qualitative protein differences were monitored; quantitative protein variations were not evaluated. Although significant differences in protein abundance can be detected by eye, the large number of protein spots present in 2DE patterns together with the large number of individual patterns required for a mutagenesis study would necessitate the use of a computerized analysis system to detect the rare quantitative protein changes indicative of gene deletions or inactivation of genes by point mutations in regulatory genes. A pilot study to search for heritable mutations induced by treatment of mice with either ethylnitrosourea or gamma radiation is underway. Samples are being monitored for quantitative changes that reduce the amount of protein by about 50%. The results of this study indicate that the key methods to improve the application of 2DE to mutation screening are to increase the number of measurable spots (i.e., improve stain sensitivity) and to decrease the spread of values for the volume measurements. Even small improvements in these areas could greatly increase the number of monitorable spots. 9 refs., 4 figs

  20. p53 gene mutation hotspots in skin cancer and ultraviolet induced mutation

    International Nuclear Information System (INIS)

    Ikehata, Hironobu

    1998-01-01

    Presence of certain hotspots is known in the mutation of p53 gene in skin cancer, which are codons 177, 196, 245, 248, 278 and 282 located in the exon 5-8. In these regions, mutations like C to T and CC to TT are frequent and thereby suggest that they are resulted from pyrimidine-dimers produced by ultraviolet light (UV). In cyclobutane pyrimidine dimerization (CPD), conversion of cytosine to thymine by deamination is suggested to be the primary reaction. Although studies using UVC (254 nm) suggesting that the mutation hotspots are low repair efficiency regions could not completely explain the all hotspots, those using UVB and sunlight (UVB and UVA) revealed that CPD was efficiently produced even in such regions as not explained by studies with UVC alone. Therefore, the latter studies are conceivably reasonable since the skin cancer is induced by natural sunlight. Exon 5-8 DNA is completely methylated and the absorption coefficient of 5-methylcytosine is 5-6 times as large as that of cytosine at wavelength around 290 nm. These indicate the importance of UVB in mutation of mammalian cells possessing the ability to methylate DNA. (K.H.)

  1. Occurrence of mutations in the epidermal growth factor receptor gene in X-ray-induced rat lung tumors

    International Nuclear Information System (INIS)

    Kitahashi, Tsukasa; Takahashi, Mami; Yamada, Yutaka

    2008-01-01

    Epidermal growth factor receptor (EGFR) gene alterations have been found in human lung cancers. However, there is no information on the factors inducing EGFR mutations. In rodents, K-ras mutations are frequently found in many lung carcinogenesis models, but hitherto, Egfr mutations have not been reported. Their presence was therefore investigated in representative lung carcinogenesis models with 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), N-nitrosobis(2-hydroxypropyl)amine (BHP), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MelQx) and ethyl carbamate (urethane), as well as X-ray irradiation. With the chemical carcinogenesis models, no mutations were detected in Egfr, which is in clear contrast to the high rates observed in either codon 12 or 61 of K-ras (21/23 of the lung tumors induced with NNK, 4/5 with MelQx, 1/4 with urethane and 7/18 with BHP). However, in the X-ray-induced lung tumors, Egfr mutations with amino acid substitution were observed in exons 18 and 21 (4/12, 33%), but no activating mutation of K-ras was detected. In addition, one and four silent mutations were identified in K-ras (exon 1) and Egfr (exons 18, 20 and 21), respectively. Most mutations in both Egfr and K-ras were G/C→A/T transitions (7/8, 88% and 31/34, 91%, respectively). Although, the mutational patterns in equivalent human lesions were not completely coincident, this first report of Egfr mutations in an experimental lung tumor model suggests that X-rays or other factors producing oxygen radicals could cause EGFR mutations in some proportion of lung cancers in humans. (author)

  2. Induced mutation in soybean (Glycine max L.) breeding

    International Nuclear Information System (INIS)

    Tulmann Neto, A.; Menten, J.O.M.; Ando, A.

    1984-01-01

    The induced mutation in soybean (Glycine max, L.) breeding is studied. Seed treatment with gamma-rays or methanesulfonic acid ethyl ester (EMs) is used in the following varieties: Parana, Santa Rosa, UFV-1, Foscarin 31 and IAC-8. The study to obtain resistance to the soybean bud blight virus and mutants resistant to rust was done. Early mutants are also researched. (M.A.C.) [pt

  3. Induced Mutations for Improving Production on Bread and Durum Wheat

    Science.gov (United States)

    Stamo, Ilirjana; Ylli, Ariana; Dodbiba, Andon

    2007-04-01

    Wheat is a very important crop and has been bred for food and its improvement is continuous from cross-breeding. Radiation and chemically induced mutations have provided variability in selection for novel varieties. Four bread and one durum wheat cultivars were exposed to gamma rays, Cs 137 with doses 10, 15 and 20 krad (2000 seeds of each dose and cultivars). We have isolated mutant plants with height reduced and on cv Progress spike without chaff.

  4. Induced Mutations for Improving Production on Bread and Durum Wheat

    International Nuclear Information System (INIS)

    Stamo, Ilirjana; Ylli, Ariana; Dodbiba, Andon

    2007-01-01

    Wheat is a very important crop and has been bred for food and its improvement is continuous from cross-breeding. Radiation and chemically induced mutations have provided variability in selection for novel varieties. Four bread and one durum wheat cultivars were exposed to gamma rays, Cs 137 with doses 10, 15 and 20 krad (2000 seeds of each dose and cultivars). We have isolated mutant plants with height reduced and on cv Progress spike without chaff

  5. RFLP analysis of rice semi-dwarf mutation induced by high energy argon ion radiation

    International Nuclear Information System (INIS)

    Zhuang Chuxiong; Hu Weimin; Mei Mantong

    1997-01-01

    Two Indica rice varieties, Bianpizhan and Xiangzhan, and their semi-dwarf mutants induced by high energy argon ion radiation, Ar-10, and Xiang-Ar-1, were examined with restriction fragment length polymorphism (RFLP) analysis by using 97 rice single copy genomic clones mapped on 12 chromosomes of molecular genetic map, combined with 5 restriction enzymes. Among the markers screened, 9 detected polymorphism were between Bianpizhen and Ar-10, and 11 detected polymorphism were between Xiangzhan and Xiang-Ar-1. Moreover, two or more restriction enzymes could generate RFLP patterns when screened with a given marker for several polymorphic markers. Based on the polymorphic allelic loci, the mutation frequencies were estimated as 5.15% and 6.39% for Ar-10 and Xiang-Ar-1 respectively. These results suggested that the nature of mutation on the DNA level was probably large genetic changes rather than point mutation. Genetic analysis and gene tagging of semi-dwarf mutation in one of the mutant line, Ar-10, indicated that this mutation was controlled by a major recessive gene, which was preliminary located on chromosome 4

  6. RFLP Analysis of rice semi dwarf mutation induced by high energy argon ion radiation

    International Nuclear Information System (INIS)

    Zhuang Chuxiong; Hu Weimin; Mei Mantong

    1997-01-01

    Two Indica rice varieties, Bianpizhan and Xiangzhan, and their semi dwarf mutants induced by high energy argon ion radiation, Ar 10, and Xiang Ar 1, were examined with restriction fragment length polymorphism(RFLP)analysis by using 97 rice single copy genomic clones mapped on 12 chromosomes of molecular genetic map, combined with 5 restriction enzymes.Among the markers screened, 9 detected polymorphism were between Bianpizhan and Ar 10, and 11 detected polymorphism were between Xiangzhan and Xiang Ar 1.Moreover, two or more restriction enzymes could generate RFLP patterns when screened with a given marker for several polymorphic markers. Based on the polymorphic allelic loci, the mutation frequencies were estimated as 5 15% and 6 39% for Ar 10 and Xiang Ar 1 respectively.These results suggested that the nature of mutation on the DNA level was probably large genetic changes rather than point mutation.Genetic analysis and gene tagging of semi dwarf mutation in one of the mutant line, Ar 10, indicated that this mutation was controlled by a major recessive gene, which was preliminary located on chromosome 4. (author)

  7. Detection of EGFR mutations with mutation-specific antibodies in stage IV non-small-cell lung cancer

    Directory of Open Access Journals (Sweden)

    Viteri Santiago

    2010-12-01

    Full Text Available Abstract Background Immunohistochemistry (IHC with mutation-specific antibodies may be an ancillary method of detecting EGFR mutations in lung cancer patients. Methods EGFR mutation status was analyzed by DNA assays, and compared with IHC results in five non-small-cell lung cancer (NSCLC cell lines and tumor samples from 78 stage IV NSCLC patients. Results IHC correctly identified del 19 in the H1650 and PC9 cell lines, L858R in H1975, and wild-type EGFR in H460 and A549, as well as wild-type EGFR in tumor samples from 22 patients. IHC with the mAb against EGFR with del 19 was highly positive for the protein in all 17 patients with a 15-bp (ELREA deletion in exon 19, whereas in patients with other deletions, IHC was weakly positive in 3 cases and negative in 9 cases. IHC with the mAb against the L858R mutation showed high positivity for the protein in 25/27 (93% patients with exon 21 EGFR mutations (all with L858R but did not identify the L861Q mutation in the remaining two patients. Conclusions IHC with mutation-specific mAbs against EGFR is a promising method for detecting EGFR mutations in NSCLC patients. However these mAbs should be validated with additional studies to clarify their possible role in routine clinical practice for screening EGFR mutations in NSCLC patients.

  8. Induced mutations in highly heterozygous vegetatively propagated grasses

    International Nuclear Information System (INIS)

    Powell, J.B.

    1976-01-01

    Experience with mutation induction of turf and forage grasses indicates that much progress can be achieved by this method. More than 300 mutations have been produced in our laboratory in the cultivars Tifgreen and Tifdwarf bermudagrass (Cynodon sp.). In the Tifway and Tifcote bermudagrasses we have demonstrated similar mutation responses. The first three clones are triploids and Tifcote is a probable tetraploid. No seeds are set on these clones. Two clones of bermudagrass, Coastal and Coastcross-1, occupy millions of hectares in the USA. Both are mutable and are known to be hybrids with 36 chromosomes. Biotypes of dallisgrass (Paspalum dilatatum Poir.) exist with 40 and 50 chromosomes and reproduce as sexual and obligate apomictic forms. Gamma-ray and thermal-neutron treatment of seed of these biotypes produced mutants that maintained the maternal characteristics in subsequent generations. Bahiagrass (Paspalum notatum Fluegge) also has sexual and apomictic biotypes. Some success was indicated for increased seed set by mutagen treatment. Kentucky bluegrass (Poa pratensis L.) is a facultative apomict with varying numbers of chromosomes in different cultivars. Gamma-ray mutagen treatment of rhizomes produced numerous mutations for plant type and disease reaction. Most mutations perpetuate themselves through the seed. The characteristic in common with all these grasses is their heterozygosity, which is maintained by the vegetative propagation or apomictic mode of reproduction. The experience in using ionizing radiation to induce heritable changes in these vegetatively propagated grasses is one of considerable success. Mutation rates in some of these irradiated grasses exceeded 65% and aberrant plants with characteristics previously never observed were found. Numerous hemizygous and heterozygous loci seem to be a sensitive target for mutagens. (author)

  9. Gamma radiation-induced heritable mutations at repetitive DNA loci in out-bred mice

    International Nuclear Information System (INIS)

    Somers, C.M.; Sharma, R.; Quinn, J.S.; Boreham, D.R.

    2004-01-01

    Recent studies have shown that expanded-simple-tandem-repeat (ESTR) DNA loci are efficient genetic markers for detecting radiation-induced germ line mutations in mice. Dose responses following irradiation, however, have only been characterized in a small number of inbred mouse strains, and no studies have applied Esters to examine potential modifiers of radiation risk, such as adaptive response. We gamma-irradiated groups of male out-bred Swiss-Webster mice with single acute doses of 0.5 and 1.0 Gy, and compared germ line mutation rates at ESTR loci to a sham-irradiated control. To test for evidence of adaptive response we treated a third group with a total dose of 1.1 Gy that was fractionated into a 0.1 Gy adapting dose, followed by a challenge dose of 1.0 Gy 24 h later. Paternal mutation rates were significantly elevated above the control in the 0.5 Gy (2.8-fold) and 1.0 Gy (3.0-fold) groups, but were similar to each other despite the difference in radiation dose. The doubling dose for paternal mutation induction was 0.26 Gy (95% CI = 0.14-0.51 Gy). Males adapted with a 0.1 Gy dose prior to a 1.0 Gy challenge dose had mutation rates that were not significantly elevated above the control, and were 43% reduced compared to those receiving single doses. We conclude that pre-meiotic male germ cells in out-bred Swiss-Webster mice are sensitive to ESTR mutations induced by acute doses of ionizing radiation, but mutation induction may become saturated at a lower dose than in some strains of inbred mice. Reduced mutation rates in the adapted group provide intriguing evidence for suppression of ESTR mutations in the male germline through adaptive response. Repetitive DNA markers may be useful tools for exploration of biological factors affecting the probability of heritable mutations caused by low-dose ionizing radiation exposure. The biological significance of ESTR mutations in terms of radiation risk assessment, however, is still undetermined

  10. Plant breeding: Induced mutation technology for crop improvement

    International Nuclear Information System (INIS)

    Novak, F.J.; Brunner, H.

    1992-01-01

    Plant breeding requires genetic variation of useful traits for crop improvement, but the desired variation is often lacking. Mutagenic agents, such as radiation and certain chemicals, can be used to induce mutations and generate genetic variations from which desirable mutants may be selected. After a brief summary of the methods currently employed in plant breeding, especially those inducing genetic engineering, this article describes the activities of the Plant Breeding Unit of the IAEA Laboratories at Seibersdorf, summarizing the research and development areas currently being pursued. The banana plant is chosen to exemplify the Laboratories' research

  11. Saccharomyces cerevisiae mutants with enhanced induced mutation and altered mitotic gene conversion.

    Science.gov (United States)

    Ivanov, E L; Kovaltzova, S V; Korolev, V G

    1989-08-01

    We have developed a method to isolate yeast (Saccharomyces cerevisiae) mutants with enhanced induced mutagenesis based on nitrous acid-induced reversion of the ade2-42 allele. Six mutants have been isolated and designated him (high induced mutagenesis), and 4 of them were studied in more detail. The him mutants displayed enhanced reversion of the ade2-42 allele, either spontaneous or induced by nitrous acid, UV light, and the base analog 6-N-hydroxylaminopurine, but not by gamma-irradiation. It is worth noting that the him mutants turned out not to be sensitive to the lethal effects of the mutagens used. The enhancement in mutation induced by nitrous acid, UV light, and 6-N-hydroxylaminopurine has been confirmed in a forward-mutation assay (induction of mutations in the ADE1, ADE2 genes). The latter agent revealed the most apparent differences between the him mutants and the wild-type strain and was, therefore, chosen for the genetic analysis of mutants, him mutations analyzed behaved as a single Mendelian trait; complementation tests indicated 3 complementation groups (HIM1, HIM2, and HIM3), each containing 1 mutant allele. Uracil-DNA glycosylase activity was determined in crude cell extracts, and no significant differences between the wild-type and him strains were detected. Spontaneous mitotic gene conversion at the ADE2 locus is altered in him1 strains, either increased or decreased, depending on the particular heteroallelic combination. Genetic evidence strongly suggests him mutations to be involved in a process of mismatch correction of molecular heteroduplexes.

  12. Effect of tumor promoters on ultraviolet light-induced mutation and mitotic recombination in Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Kunz, B.A.; Hannan, M.A.; Haynes, R.H.

    1980-01-01

    Recently, it has been suggested that mitotic recombination is involved in tumor promotion. On this basis, one might expect tumor promoters to be recombinagenic. D7 is a diploid strain of yeast in which both mutation and mitotic recombination can be measured. We have used this strain to assay the known tumor promoters, iodacetate, anthralin, and 12-0-tetradecanoylphorbol-13-acetate, and the cocarcinogen, catechol, for mutagenicity, recombinagenicity, and the ability to enhance ultraviolet light (UV)-induced genetic events. In the absence of preirradiation with UV, iodoacetate was found to be recombinagenic whereas catechol was mutagenic; however, in both cases, the effects were small. Iodoacetate, anthralin, and catechol potentiated UV-induced mitotic crossing-over, aberrant colony formation, and mutation, while catechol also increased UV-induced gene conversion. We were unable to detect any mutagenic or recombinagenic effect of 12-0-tetradecanoyl-phorbol-13-acetate in either whole cells or spheroplasts. Our results do not indicate any consistent correlation between tumor-promoting activity and the ability of an agent to induce mitotic recombination in yeast. However, the ability to potentiate UV-induced mutation and mitotic recombination may reflect the cocarcinogenic activity of certain promoters

  13. Somatic mutations in stilbene estrogen-induced Syrian hamster kidney tumors identified by DNA fingerprinting

    Directory of Open Access Journals (Sweden)

    Roy Deodutta

    2004-01-01

    Full Text Available Abstract Kidney tumors from stilbene estrogen (diethylstilbestrol-treated Syrian hamsters were screened for somatic genetic alterations by Random Amplified Polymorphic DNA-polymerase chain-reaction (RAPD-PCR fingerprinting. Fingerprints from tumor tissue were generated by single arbitrary primers and compared with fingerprints for normal tissue from the same animal, as well as normal and tumor tissues from different animals. Sixty one of the arbitrary primers amplified 365 loci that contain approximately 476 kbp of the hamster genome. Among these amplified DNA fragments, 44 loci exhibited either qualitative or quantitative differences between the tumor tissues and normal kidney tissues. RAPD-PCR loci showing decreased and increased intensities in tumor tissue DNA relative to control DNA indicate that loci have undergone allelic losses and gains, respectively, in the stilbene estrogen-induced tumor cell genome. The presence or absence of the amplified DNA fragments indicate homozygous insertions or deletions in the kidney tumor DNA compared to the age-matched normal kidney tissue DNA. Seven of 44 mutated loci also were present in the kidney tissues adjacent to tumors (free of macroscopic tumors. The presence of mutated loci in uninvolved (non-tumor surrounding tissue adjacent to tumors from stilbene estrogen-treated hamsters suggests that these mutations occurred in the early stages of carcinogenesis. The cloning and sequencing of RAPD amplified loci revealed that one mutated locus had significant sequence similarity with the hamster Cyp1A1 gene. The results show the ability of RAPD-PCR to detect and isolate, in a single step, DNA sequences representing genetic alterations in stilbene estrogen-induced cancer cells, including losses of heterozygosity, and homozygous deletion and insertion mutations. RAPD-PCR provides an alternative molecular approach for studying cancer cytogenetics in stilbene estrogen-induced tumors in humans and experimental

  14. Cytosine arabinoside enhancement of gamma irradiation induced mutations in human T-lymphocytes

    International Nuclear Information System (INIS)

    O'Neill, J.P.; Sullivan, L.M.; Hunter, T.C.; Nicklas, J.A.

    1991-01-01

    The frequency of 6-thioguanine resistant (TGr) mutants induced in human G0 phase T-lymphocytes by 200 cGy of gamma irradiation is greatly enhanced by incubation with cytosine arabinoside (ara-C) after irradiation. The mutant frequency increased with increasing incubation time in ara-C for up to 2 hr. This mutation induction required a phenotypic expression time of 5-8 days mass culture growth, similar to that found with mutants induced by 300 cGy of irradiation alone. Southern blot analysis of 40 isolated mutant clones revealed 8 independent mutations by T-cell receptor (TCR) gene rearrangement patterns. Four of these eight showed hprt gene structural alterations (0.50). An alternative method to allow phenotypic expression was developed to minimize the isolation of hprt/TCR sibling mutants. The use of in situ expression in the microtiter dish wells resulted in the isolation of 17 independent mutations in 19 mutant clones. Ten of these 17 mutations showed hprt structural alterations (0.59). The high fraction of mutations involving structural alterations detected by Southern blot analysis is consistent with the known induction of chromosome aberrations by irradiation plus ara-C treatment. We propose that both the increase in Mf and the increase in the incidence of hprt gene structural alterations are due to the accumulation of strand breaks in repairing regions of DNA under these conditions of ara-C induced inhibition of repair. We further propose that upon release of the ara-C inhibition, these repairing regions can interact to yield both gene mutations and chromosome aberrations

  15. Utilization of induced mutations in improving legumes in Egypt

    International Nuclear Information System (INIS)

    Abo-Hegazi, A. M. T.

    1993-01-01

    More than one hundred articles published by Egyptian research workers dealing with the improvement of some seed-legumes through radiation, radioisotopes, chemical mutagens and induced mutations are briefly summarized and discussed from the point of view of a mutation breeder working in this field since 1961. Articles on faba bean (Vicia faba L.), soybean (Glycine Max L.), lentils (Lens culinaris), chick-pea (Cicer arietinum L.), lupin (Lupinus termis), peas=pea (Pisum sativum L.), cowpea (Vigna sinensis, savi), and fenugreek-helba (Trigonella foenum gracum L.) are reviewed. A very few number of promising mutations have been induced. However, none of them are utilized neither in conventional breeding programs nor as cultivars. This may be due to the lack of central plans and organization between efforts or research work being carried in various institutions. Joint plants and cooperation between research institutions, not only in Egypt but also among the Arab countries, are required in this field which may help in closing the wide gab between production and consumption os seed legumes. (author)

  16. Detection of new MHC mutations in mice by skin grafting, tumor transplantation and monoclonal antibodies: a comparison

    International Nuclear Information System (INIS)

    Egorov, I.K.; Egorov, O.S.

    1988-01-01

    Two mechanisms of major histocompatibility complex (MHC) mutations have been described in mice: gene conversion and homologous but unequal recombination. However, the knowledge of mutations in MHC is incomplete because studies have been limited almost exclusively to two haplotypes, H-2/sup b/ and H-2/sup d/, while hundreds of haplotypes exist in nature; it has been biased by the use of only one procedure of screening for mutation, skin grafting. The authors used three procedures to screen for MHC mutations: (1) conventional techniques of skin grafting, (2) syngeneic tumor transplantation and (3) typing with monoclonal anti-MHC antibodies (mAbs) and complement. The faster technique of tumor transplantation detected mutants similar to those discovered by skin grafting technique. Screening with mAbs allowed us to detect both mutants that are capable of rejecting standard skin grafts and those that are silent in skin grafting tests, and which therefore resulted in a higher apparent mutation frequency. Two mutants of the H-2/sup a/ haplotype were found that carry concomitant class I and class II antigenic alterations. Both MHC mutants silent in skin grafting tests and mutants carrying concomitant class I and class II alterations have never been studied before and are expected to reveal new mechanisms of generating MHC mutations. 1-Ethyl-1-nitrosourea (ENU) failed to induce de novo MHC mutations in our skin grafting series

  17. Rapid detection of single nucleotide mutation in p53 gene based on ...

    Indian Academy of Sciences (India)

    mutation.27 Nevertheless, more than 50% of all human tumors contain p53 mutation; ... gene mutation detection in various fields of biology and medicine persuaded us to find ..... Yola M L, Eren T and Atar N 2014 Electrochim. Acta. 125 38. 26.

  18. Molecular alterations underlying the spontaneous and γ-ray-induced point mutations at the white locus of Drosophila Melanogaster

    International Nuclear Information System (INIS)

    Aleksandrova, M.V.; Lapidus, I.L.; Aleksandrov, I.D.; Karpovskij, A.L.

    1996-01-01

    The white locus in D.Melanogaster was selected as a target gene for the study of the mutational spectra of spontaneously arising and radiation-induced gene mutations in a whole organism. Analysis of 6 spontaneous and 73 γ-ray-induced white mutations by a combination of cytological, genetic and molecular techniques revealed that on the chromosomal and genetic levels all spontaneous mutations showed themselves to be point mutants. The share of such mutants among all heritable radiation-induced gene mutations is about 40%, whereas the rest ones are due to exchange breaks (8%) as well as multilocus, single-locus or partial-locus (intragenic) deletions (52%). The DNAs from 4 spontaneous and 17 γ-ray-induced point mutants were analysed by Southern blot-hybridization. The three spontaneous and 7 radiation mutants showed an altered DNA sequence at the left (distal) half of the white gene due to insertion or DNA rearrangement. The rest (58%) of the radiation-induced point mutations did not indicate any alternations in this part of the gene as detected by this technique and probes employed. 15 refs., 3 figs., 1 tab

  19. Rapid detection of RB1 recurrent mutations in retinoblastoma by ...

    Indian Academy of Sciences (India)

    In about half of the patients, one mutation is inherited via the germinal cells, while in the .... mutational hot spots in the RB1 gene, making genetic testing complex and challenging ... by direct sequencing. High normal background in sequenc-.

  20. Induced plasmon mutations affecting the growth habit of peanuts, A. hypogaea L

    International Nuclear Information System (INIS)

    Levy, A.; Ashri, A.

    1978-01-01

    The effectiveness of the acridines ethidium bromide (EB) and acriflavine in inducing plasmon mutations was compared with the alkylating agents ethyl methanesulphonate (EMS) and diethyl sulphate and to γ-rays. The growth habit (trailing versus bunch) of peanuts (A. hypogaea), controlled by genic-cytoplasmic interactions, was utilized. Breeding tests distinguishing nuclear from plasmon mutations were developed and are described in detail. Plasmon mutations were induced, but there were differences in mutation yields between the cultivars and the mutagens. (Auth.)

  1. Induced mutations for improvement of grain legume production

    International Nuclear Information System (INIS)

    1980-11-01

    After an introduction on plant science research in Malaysia concerning crop breeding, 22 research reports are presented, 17 of which are analyzed individually and constitute separate INIS references. The remaining 5 were essentially concerned with only future applications of nuclear technology: a paper by V.L. Chopra (India) on mutation breeding for partial disease resistance of wheat; by H.H. Hoppe (Federal Republic of Germany) on mechanisms of resistance against Uromyces in Phaseolus vulgaris; by I.S. Santos (Philippines) on induction evaluation and utilization of beneficial mutations in the winged bean (Psophocarpus tetragonolobus), where gamma rays and fast neutrons will be used as well as other mutagens; by F. Saccardo (Italy) on breeding for disease resistance in peas and other vegetables (short communication only); and by E. Balazs and I. Sziraki (Hungary) on in vitro studies on virus resistance of legumes, including virus-host interaction studies involving gamma irradiation (short communication only). The conclusions and recommendations of the Regional Seminar on Induced Mutations for the Improvement of Grain Legumes in S.E. Asia 1975 (IAEA-203, 1977) were considered and generally endorsed, with some clarification. Conclusions and recommendations are given on p.121-126

  2. Detection of Ultra-Rare Mitochondrial Mutations in Breast Stem Cells by Duplex Sequencing.

    Directory of Open Access Journals (Sweden)

    Eun Hyun Ahn

    Full Text Available Long-lived adult stem cells could accumulate non-repaired DNA damage or mutations that increase the risk of tumor formation. To date, studies on mutations in stem cells have concentrated on clonal (homoplasmic mutations and have not focused on rarely occurring stochastic mutations that may accumulate during stem cell dormancy. A major challenge in investigating these rare mutations is that conventional next generation sequencing (NGS methods have high error rates. We have established a new method termed Duplex Sequencing (DS, which detects mutations with unprecedented accuracy. We present a comprehensive analysis of mitochondrial DNA mutations in human breast normal stem cells and non-stem cells using DS. The vast majority of mutations occur at low frequency and are not detectable by NGS. The most prevalent point mutation types are the C>T/G>A and A>G/T>C transitions. The mutations exhibit a strand bias with higher prevalence of G>A, T>C, and A>C mutations on the light strand of the mitochondrial genome. The overall rare mutation frequency is significantly lower in stem cells than in the corresponding non-stem cells. We have identified common and unique non-homoplasmic mutations between non-stem and stem cells that include new mutations which have not been reported previously. Four mutations found within the MT-ND5 gene (m.12684G>A, m.12705C>T, m.13095T>C, m.13105A>G are present in all groups of stem and non-stem cells. Two mutations (m.8567T>C, m.10547C>G are found only in non-stem cells. This first genome-wide analysis of mitochondrial DNA mutations may aid in characterizing human breast normal epithelial cells and serve as a reference for cancer stem cell mutation profiles.

  3. MutScan: fast detection and visualization of target mutations by scanning FASTQ data.

    Science.gov (United States)

    Chen, Shifu; Huang, Tanxiao; Wen, Tiexiang; Li, Hong; Xu, Mingyan; Gu, Jia

    2018-01-22

    Some types of clinical genetic tests, such as cancer testing using circulating tumor DNA (ctDNA), require sensitive detection of known target mutations. However, conventional next-generation sequencing (NGS) data analysis pipelines typically involve different steps of filtering, which may cause miss-detection of key mutations with low frequencies. Variant validation is also indicated for key mutations detected by bioinformatics pipelines. Typically, this process can be executed using alignment visualization tools such as IGV or GenomeBrowse. However, these tools are too heavy and therefore unsuitable for validating mutations in ultra-deep sequencing data. We developed MutScan to address problems of sensitive detection and efficient validation for target mutations. MutScan involves highly optimized string-searching algorithms, which can scan input FASTQ files to grab all reads that support target mutations. The collected supporting reads for each target mutation will be piled up and visualized using web technologies such as HTML and JavaScript. Algorithms such as rolling hash and bloom filter are applied to accelerate scanning and make MutScan applicable to detect or visualize target mutations in a very fast way. MutScan is a tool for the detection and visualization of target mutations by only scanning FASTQ raw data directly. Compared to conventional pipelines, this offers a very high performance, executing about 20 times faster, and offering maximal sensitivity since it can grab mutations with even one single supporting read. MutScan visualizes detected mutations by generating interactive pile-ups using web technologies. These can serve to validate target mutations, thus avoiding false positives. Furthermore, MutScan can visualize all mutation records in a VCF file to HTML pages for cloud-friendly VCF validation. MutScan is an open source tool available at GitHub: https://github.com/OpenGene/MutScan.

  4. The effect of spermine on spontaneous and UV-induced mutations in Schizosaccharomyces pombe

    International Nuclear Information System (INIS)

    Prendergast, J.A.; Kamra, O.P.; Nasim, A.

    1984-01-01

    The effect of different concentrations of spermine on spontaneous and UV-induced mutation in the adenine forward mutation system of Schizosaccharomyces pombe was investigated. The effect of spermine on spontaneous mutation was studied in 5 mutator strains (mut 1-4, mut 1-23, mut 2-9, mut 2-20 and mut 3-21) and on UV-induced mutation in a pigmented adenine-requiring strain and its radiation-sensitive derivative (rad 13). The effect of spermine exposure on mutation induction before and after UV irradiation was also investigated. Spermine increased spontaneous forward mutation in the mut 1-4 strain by 47% and enhanced UV-induced forward mutation 2-fold in the rad 13 and normal pigmented strains. No antimutagenic effect of spermine was seen in any of the strains tested. This is in marked contrast to the antimutagenic effect of spermine observed with bacteria. (Auth.)

  5. Gamma-ray induced mutation breeding in tree fruit crops

    International Nuclear Information System (INIS)

    Ito, Yuji

    1998-01-01

    In many vegetatively propagated crops and tree fruit crops, spontaneous mutations have played an important role in the development of cultivars. Thus, induced mutation breeding has been thought to be a promising way to improve commercially important cultivars. At the Institute of Radiation Breeding (IRB), studies on induced mutation breeding of temperate zone fruit trees using gamma-rays have been performed since 1962. Black spot disease, caused by Alternaria alternata Japanese pear pathotype, is one of the most serious diseases of Japanese pear (Pyrus pyrifolia NAKAI var. culta NAKAI) in Japan. It is known that some Japanese pear cultivars are completely resistant to the disease. The pathogenic fungi produces host-specific toxins (named AK-toxin) (Tanaka 1993, Otani et al. 1973). The susceptibility of Japanese pear is controlled by a single dominant gene (Kozaki 1973). To improve the Japanese pear cultivar 'Nijisseiki', which is highly susceptible to black spot disease, young grafted plants of 'Nijisseiki' have been irradiated chronically in the Gamma Field of the IRB since 1962. In 1981, one twig of a tree planted at a distance of 53 m from the 60 Co source with an exposure rate of 0.138 Gy/day (20hr-irradiation) was selected as the first resistant mutant. It was designated as cultivar 'Gold Nijisseiki' and released in 1990. A selection method for mutants resistant to black spot disease using the pathogen produced toxin and pear leaf disks was established. It is a simple and stable selection method. Up to the present, three mutant cultivars resistant to black spot disease have been bred at the IRB by chronic and acute gamma-ray irradiation. They showed intermediate resistance compared with the completely resitan cultivar 'Choujuurou' and highly susceptible cultivar 'Nijisseiki'. We obtained some apple mutants resistant to alternaria leaf blotch disease using toxin and leaf disks and are also attempting to obtain mutant resistant to some disease in other temperate

  6. Screening for duplications, deletions and a common intronic mutation detects 35% of second mutations in patients with USH2A monoallelic mutations on Sanger sequencing.

    Science.gov (United States)

    Steele-Stallard, Heather B; Le Quesne Stabej, Polona; Lenassi, Eva; Luxon, Linda M; Claustres, Mireille; Roux, Anne-Francoise; Webster, Andrew R; Bitner-Glindzicz, Maria

    2013-08-08

    23 (35%) of 'missing' mutations in Usher type 2 probands with only a single heterozygous USH2A mutation detected with Sanger sequencing could be attributed to deletions, duplications or a pathogenic deep intronic variant. Future mutation detection strategies and genetic counselling will need to take into account the prevalence of these types of mutations in order to provide a more comprehensive diagnostic service.

  7. Genetic improvement of black gram using induced mutations

    International Nuclear Information System (INIS)

    Pawar, S.E.; Manjaya, J.G.; Souframanien, J.; Bhatkar, S.M.

    2000-01-01

    Induced mutagenesis is an important tool for creating genetic variability in crop plants and has played a significant role in the development of many crop varieties. Genetic improvement of black gram (Vigna mungo L. Hepper) through induced mutations has been in progress at BARC for the past three decades. Mutation studies of genotype EC-168200 have resulted in isolating large number of mutants with distinct morphological characters. TAU-5, an early maturing mutant was identified as a resistant donor for yellow mosaic virus (YMV) disease by the All India Pulse Improvement Project, ICAR, Kanpur. TAU-5 was used in cross breeding with elite cultivars like T-9, TPU-4 and LBG-17. Twelve selections with high yield potential suitable for both kharif and rabi cultivation have been developed. One of the selections TU94-2 has been released for commercial cultivation for southern zone during 1999. The work on the development of YMV resistant genotypes is in progress and will be discussed. (author)

  8. Use of γ-ray-induced mutations in the genome era in rice

    International Nuclear Information System (INIS)

    Kusaba, Makoto

    2007-01-01

    Ionizing radiation has been used for inducing mutations and improving crops since the discovery by STADLER (1928) that X-rays could induce mutations in barley. At the end of 2004, the whole genome sequence of rice was determined (INTERNATIONAL RICE GENOME SEQUENCING PROJECT, 2005). What can γ-ray-induced mutations contribute now that this has been achieved? One answer could be the elucidation of the functions of the numerous genes revealed by the complete sequence of the rice genome. This includes identification of mutants through reverse genetics and the isolation of genes containing mutations through forward genetics using molecular markers and sequence information. Another answer could be mutation breeding using reverse genetics. But first we must know what kind of DNA lesions are caused by γ-rays. In this article, I describe the production of DNA lesions, and then discuss how γ-ray-induced mutations can contribute to the elucidation of gene function and to mutation breeding. (author)

  9. High resolution melting analysis: a rapid and accurate method to detect CALR mutations.

    Directory of Open Access Journals (Sweden)

    Cristina Bilbao-Sieyro

    Full Text Available The recent discovery of CALR mutations in essential thrombocythemia (ET and primary myelofibrosis (PMF patients without JAK2/MPL mutations has emerged as a relevant finding for the molecular diagnosis of these myeloproliferative neoplasms (MPN. We tested the feasibility of high-resolution melting (HRM as a screening method for rapid detection of CALR mutations.CALR was studied in wild-type JAK2/MPL patients including 34 ET, 21 persistent thrombocytosis suggestive of MPN and 98 suspected secondary thrombocytosis. CALR mutation analysis was performed through HRM and Sanger sequencing. We compared clinical features of CALR-mutated versus 45 JAK2/MPL-mutated subjects in ET.Nineteen samples showed distinct HRM patterns from wild-type. Of them, 18 were mutations and one a polymorphism as confirmed by direct sequencing. CALR mutations were present in 44% of ET (15/34, 14% of persistent thrombocytosis suggestive of MPN (3/21 and none of the secondary thrombocytosis (0/98. Of the 18 mutants, 9 were 52 bp deletions, 8 were 5 bp insertions and other was a complex mutation with insertion/deletion. No mutations were found after sequencing analysis of 45 samples displaying wild-type HRM curves. HRM technique was reproducible, no false positive or negative were detected and the limit of detection was of 3%.This study establishes a sensitive, reliable and rapid HRM method to screen for the presence of CALR mutations.

  10. 70 years induced mutations - To be reconsidered? Topic for discussion

    International Nuclear Information System (INIS)

    Micke, A.

    1996-01-01

    According to the prevailing concept at that time, ''qualitative traits'' were assumed to be controlled by one or very few genes, ''quantitative traits'' by many genes. One had already learned that genes could freely recombine, unless they were tightly linked in a chromosomal section. Great attention was paid to ''gene/environment interactions'', separating traits with ''high heritability'' from those with ''low heritability''. Mutagenesis, however, was supposed to be capable of altering all genes irrespective of their chromosomal location, linkage group or level of heritability. Those with ''high heritability'' of course were easier to handle and identified as the more promising targets for mutation induction. When plant breeders speak about gene/environment interactions, the environment is usually considered under the aspect of physical and chemical conditions outside the plant (e.g. location, year, stress), supporting or restricting performance. This neglects the fact that interaction among genes creates some kind of ''genetic environment''. Plant breeders tend to focus on particular genes assumed to be responsible for traits relevant for cultivar improvement. The other genes are downgraded by being lumped into the ''genetic background''. This thinking also prevailed so far in application of induced mutations in breeding programmes

  11. Jatropha curcas improvement Induced mutation: Thies University Senegal

    International Nuclear Information System (INIS)

    Diédhiou, Ibrahima

    2011-06-01

    The objectives are: 1. to collect accessions of Jatropha curcas in Senegal and establish the genetic variability of this collection. 2. to improve the oil yield of Jatropha curcas by using radiation induced mutation methods to produce highly productive genotypes adapted to local conditions. The choice of Jatropha Curcas is explained by: * Intensive cultivation of Jatropha curcas initiated in many countries of West Africa to produce biodiesel. *There is a craze of private companies to promote this new agricultural value chain. * Jobs and substantial revenues are expected for the rural. *Unfortunately, there is little reliable knowledge to support this dynamic development. Also, the preliminary results showed a high variability of agro-morphological traits in local accessions which could affect negatively the profitability.

  12. Improving protein quality of soybean through induced mutations

    International Nuclear Information System (INIS)

    Manjaya, J.G.

    2011-01-01

    Soybean is one of the most economical and nutritious food packed with basic nutrients that combat diseases stemming from mal- and under-nutrition. Despite its rich nutritional profile, use of soybean in food has been limited because soybean proteins are often associated with compounds, which could exert a negative impact on the nutritional quality of the protein. Trypsin inhibitor (TI) is one of the important anti-nutritional factors that exert negative effect by causing growth inhibition. Soybean cultivar VLS-2 was irradiated with 250 Gy gamma rays in a gamma cell (200) with 60 Co source installed at BARC to induce mutations for low trypsin inhibitor content. Three mutants with lower levels of TI content were identified and can be utilized for developing elite varieties of soybean. (author)

  13. Targeted mutations induced by a single acetylaminofluorene DNA adduct in mammalian cells and bacteria

    International Nuclear Information System (INIS)

    Moryia, M.; Takeshita, M.; Johnson, F.; Peden, K.; Will, S.; Grollman, A.P.

    1988-01-01

    Mutagenic specificity of 2-acetylaminofluorene (AAF) has been established in mammalian cells and several strains of bacteria by using a shuttle plasmid vector containing a single N-(deoxyguanosin-8-yl)acetylaminofluorene (C8-dG-AAF) adduct. The nucleotide sequence of the gene conferring tetracycline resistance was modified by conservative codon replacement so as to accommodate the sequence d(CCTTCGCTAC) flanked by two restriction sites, Bsm I and Xho I. The corresponding synthetic oligodeoxynucleotide underwent reaction with 2-(N-acetoxy-N-acetylamino)-fluorene (AAAF), forming a single dG-AAF adduct. This modified oligodeoxynucleotide was hybridized to its complementary strand and ligated between the Bsm I and Xho I sites of the vector. Plasmids containing the C8-dG-AAF adduct were used to transfect simian virus 40-transformed simian kidney (COS-1) cells and to transform several AB strains of Escherichia coli. Colonies containing mutant plasmides were detected by hybridization to 32 P-labeled oligodeoxynucleotides. Presence of the single DNA adduct increased the mutation frequency by 8-fold in both COS cells and E. coli. Over 80% of mutations detected in both systems were targeted and represented G x C → C x G or G x C → T x A transversions or single nucleotide deletions. The authors conclude that modification of a deoxyguanosine residue with AAF preferentially induces mutations targeted at this site when a plasmid containing a single C8-dG-AAF adduct is introduced into mammalian cells or bacteria

  14. Heteroduplex analysis of the dystrophin gene: Application to point mutation and carrier detection

    Energy Technology Data Exchange (ETDEWEB)

    Prior, T.W.; Papp, A.C.; Snyder, P.J.; Sedra, M.S.; Western, L.M.; Bartolo, C.; Mendell, J.R. [Ohio State Univ., Columbus, OH (United States); Moxley, R.T. [Univ. of Rochester Medical Center, NY (United States)

    1994-03-01

    Approximately one-third of Duchenne muscular dystrophy patients have undefined mutations in the dystrophin gene. For carrier and prenatal studies in families without detectable mutations, the indirect restriction fragment length polymorphism linkage approach is used. Using a multiplex amplification and heteroduplex analysis of dystrophin exons, the authors identified nonsense mutations in two DMD patients. Although the nonsense mutations are predicted to severely truncate the dystrophin protein, both patients presented with mild clinical courses of the disease. As a result of identifying the mutation in the affected boys, direct carrier studies by heteroduplex analysis were extended to other relatives. The authors conclude that the technique is not only ideal for mutation detection but is also useful for diagnostic testing. 29 refs., 4 figs.

  15. Induced mutations in apomictic variety of maize-tripsacum hybrid

    International Nuclear Information System (INIS)

    Yudin, B.F.; Lukina, L.A.

    1983-01-01

    Three generations of six mutants obtained by γ- and x-irradiation of seeds of highly apomictic variety of 38 chromosome maize-tripsacum hybrid have been studied. Radiomutants detected in M 2 preserved the mother type and constance in M 3 and M 4 . One of the mutants, as an exception, manifested somatic splitting, which resulted in the appearance of a new apomictic clone. Irradiation and mutation in some cases were accompanied by the appearance of seedlings with high chromosome numbers in mutant posterity, including apomicts with doubled number of chromosomes, as well as the increase of total part of sexual reproduction; the latter circumstance is considered as a result of modificator balance change caused by treatments. Doubling of chromosome number in 38-chromosome apomicts, according to preliminary data, does not affect significantly the way of reproduction; 76-chromosome forms preserve a high degree of a regular apomixis

  16. Detection of MPL mutations by a novel allele-specific PCR-based strategy.

    Science.gov (United States)

    Furtado, Larissa V; Weigelin, Helmut C; Elenitoba-Johnson, Kojo S J; Betz, Bryan L

    2013-11-01

    MPL mutation testing is recommended in patients with suspected primary myelofibrosis or essential thrombocythemia who lack the JAK2 V617F mutation. MPL mutations can occur at allelic levels below 15%, which may escape detection by commonly used mutation screening methods such as Sanger sequencing. We developed a novel multiplexed allele-specific PCR assay capable of detecting most recurrent MPL exon 10 mutations associated with primary myelofibrosis and essential thrombocythemia (W515L, W515K, W515A, and S505N) down to a sensitivity of 2.5% mutant allele. Test results were reviewed from 15 reference cases and 1380 consecutive specimens referred to our laboratory for testing. Assay performance was compared to Sanger sequencing across a series of 58 specimens with MPL mutations. Positive cases consisted of 45 with W515L, 6 with S505N, 5 with W515K, 1 with W515A, and 1 with both W515L and S505N. Seven cases had mutations below 5% that were undetected by Sanger sequencing. Ten additional cases had mutation levels between 5% and 15% that were not consistently detected by sequencing. All results were easily interpreted in the allele-specific test. This assay offers a sensitive and reliable solution for MPL mutation testing. Sanger sequencing appears insufficiently sensitive for robust MPL mutation detection. Our data also suggest the relative frequency of S505N mutations may be underestimated, highlighting the necessity for inclusion of this mutation in MPL test platforms. Copyright © 2013 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

  17. Induced mutation for the improvement of soybean (Glycine max L.)

    International Nuclear Information System (INIS)

    Asencion, A.B.; Lapade, A.G.; Grafia, A.O.; Barrida, A.C.; Veluz, A.M.; Marbella, L.J.

    2004-01-01

    A study on the use of gamma radiation in the induction of mutations in eight varieties of soybean was conducted. The radiosensitivity of the seeds of both local and introduced soybean varieties was determined. The effects of gamma radiation in the M1 generation were evaluated. Percentage germination was not affected by doses of 200 and 250 Gy gamma radiation in all the eight soybean varieties. No significant differences in seedling height were observed at 200 Gy and the control except for the 250 Gy in BPI-Sy4, PSB-Sy4 and PSB-Sy5. In the Vietnamese varieties, significant differences in seedling height were obtained in doses of 200, 250 Gy and the control except for the variety AKO 6. There was significant difference in plant height of mature plants between the control and treatment dose of 250 Gy in varieties DT 95 and AKO 6. Likewise, significant differences in mature plant height were noted between the control and those at 250 Gy in local varieties BPI-Sy4, PSB-Sy5 and NSIC-Sy8. The number of days to flower was not affected by gamma radiation in both the local and introduced varieties. There were significant differences in the number of pods per plant between the control and a low dose of 200 Gy in Vietnamese variety DT 96 and the local varieties PSB-Sy4, PSB-Sy5 and NSIC-Sy8. The 3 types of chlorophyll mutation induced by gamma rays in the local varieties were: chlorina, striatia,and spotted yellow. Only chlorina mutant was induced in the introduced varieties. Desirable mutants that are early and high yielding were selected. Results of the drought tolerance tests indicated that the number of days to flowering of the control and 8 varieties was not affected by the duration of irrigation withdrawals 20,30,40 and 50 days after planting. Significant differences in seed weight among the different varieties were noted only in 20 and 30 day irrigation withdrawal treatment. When the effects of the different treatments were analyzed on a per variety bases, some of the

  18. Electrospray ionisation mass spectrometry facilitates detection of fibrinogen (Bbeta 14 Arg --> Cys) mutation in a family with thrombosis.

    Science.gov (United States)

    Brennan, S O; Hammonds, B; Spearing, R; George, P M

    1997-12-01

    We report the first direct detection of a fibrinogen mutation by electrospray ionisation mass spectrometry. The propositus, from a family with a history of thrombosis, came to attention after a pulmonary embolism subsequent to a spontaneous abortion. Prolonged thrombin (41 s) and reptilase times (26 s) together with an impairment of fibrinopeptide B release suggested a mutation at the thrombin cleavage site of the Bbeta chain. Direct mass analysis of purified fibrin chains from a thrombin induced clot showed that 50% of the Bbeta chains remained uncleaved. The measured mass of the mono sialo isoform of this uncleaved chain was 54150 Da, compared to a value of 54198 Da for normal Bbeta chains. This decrease of 48 Da in the intact protein is indicative of either a Bbeta 14 Arg to Cys, or Arg to Leu substitution. Heterozygosity for the Bbeta 14 Arg --> Cys mutation was verified by PCR amplification and DNA sequence analysis.

  19. Comparison of somatic mutation frequencies at HGPRT locus induced by radiation and chemical pollutant from energy system

    International Nuclear Information System (INIS)

    Xu Honglan; Cao Yi; Duan Zhikai; Wu Qiqing; Chen Ying; Zhang Shuxian

    1998-12-01

    The somatic induction frequencies of mutation at the hypoxanthine-guanine phosphoribosyl transferase (HGPRT) locus induced by 60 Co γ-rays and Benzo-a-pyrene (B(a)P), which are representative of hazardous emission and pollutant from nuclear energy cycle and fossil-fuelled energy cycle respectively, were detected by using forward mutation assay and cloning technique in both V 79 Chinese hamster cells and human peripheral blood T-lymphocytes. Resistant mutants were selected with 6-thioguanine (6-TG). Dose-response curves and mathematical expressions were obtained for mutation frequencies and survival following γ-ray and B(a)P(+S 9 ) treatments. The dose ranges for the two mutagens were compared when they induced the same mutation frequencies. In V 79 /HGPRT assay system, when the mutation frequencies were 5∼35 mutants/10 6 cells the response of γ-rays in the dose range from 0.93∼4.96 Gy at dose rate of 1.16 Gy/min is nearly equivalent to that in the B(a)P dose range from 0.52∼4.27 μg/ml. By using cloning technique in T-lymphocytes, when the mutation frequencies were 1∼14 mutants/10 5 cells the response of γ-rays in the dose range from 0.05∼4.77 Gy at dose rate of 1.03 Gy/min is nearly equivalent to that in the B(a)P dose range from 0.15∼7.36 μg/ml. When the survival fraction is 37%, the mutation frequency induced by B(a)P is higher than that induced by 60 Co γ-rays

  20. Induction of somatic mutations by low-dose X-rays: the challenge in recognizing radiation-induced events.

    Science.gov (United States)

    Nagashima, Haruki; Shiraishi, Kumiko; Ohkawa, Saori; Sakamoto, Yuki; Komatsu, Kenshi; Matsuura, Shinya; Tachibana, Akira; Tauchi, Hiroshi

    2017-10-19

    It is difficult to distinguish radiation-induced events from spontaneous events during induction of stochastic effects, especially in the case of low-dose or low-dose-rate exposures. By using a hypersensitive system for detecting somatic mutations at the HPRT1 locus, we investigated the frequency and spectrum of mutations induced by low-dose X-rays. The mutant frequencies induced by doses of >0.15 Gy were statistically significant when compared with the spontaneous frequency, and a clear dose dependency was also observed for mutant frequencies at doses of >0.15 Gy. In contrast, mutant frequencies at doses of 0.2 Gy. Our observations suggest that there could be a critical dose for mutation induction at between 0.1 Gy and 0.2 Gy, where mutagenic events are induced by multiple DNA double-strand breaks (DSBs). These observations also suggest that low-dose radiation delivered at doses of <0.1 Gy may not result in DSB-induced mutations but may enhance spontaneous mutagenesis events. © The Author 2017. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  1. [Identification of an ideal noninvasive method to detect A3243G gene mutation in MELAS syndrome].

    Science.gov (United States)

    Ma, Yi-nan; Fang, Fang; Yang, Yan-ling; Zhang, Ying; Wang, Song-tao; Xu, Yu-feng; Pei, Pei; Yuan, Yun; Bu, Ding-fang; Qi, Yu

    2008-12-16

    To identify a better non-invasive method to detect the carrier of mitochondrial A3243G mutation, a cause of mitochondrial encephalopathy-lactic acidosis-stroke like episode (MELAS) syndrome. DNA was extracted from the peripheral blood, urine, hair follicle, and saliva of 25 MELAS syndrome patients carrying A3243G mutation and their mothers and other maternal relatives, 33 persons in number, and the muscle tissues from 5 patients obtained by biopsy. A3243G mutation was detected by PCR-RFLP method, and the A3243G mutation ratio was identified by measuring the density of each band and calculation with the software AlphaEase 5.0. A3243G mutations were detected in all tissues of the 25 MELAS patients. The A3243G mutation ratio in urine was 62% +/- 9%, significantly higher than that in the blood [(36% +/- 10%), t = -11.13, P < 0.01]. A3243G mutations were detected in at least one tissue of the 28 maternal relatives. The A3243G mutation rates in their urine samples was 33.0% (5.0% - 70.4%), significantly higher than that in their blood samples [8.0% (0 - 33.3%), z = -4.197, P < 0.01]. There was no significant difference in A3243G mutation ratio among the samples of hair follicle, saliva, and blood. The A3243G mutation ratio in urine is significantly higher than those in blood samples of the patients and their maternal relatives. A noninvasive method, A3243G mutation ratio analysis of urine is superior to that in blood.

  2. Grain legume cultivars derived from induced mutations, and mutations affecting nodulation

    International Nuclear Information System (INIS)

    Bhatia, C.R.; Maluszynski, M.; Nichterlein, K.; Zanten, L. van

    2001-01-01

    Two hundred and sixty-five grain legume cultivars developed using induced mutations have been released in 32 countries. A maximum number of cultivars have been released in soybean (58), followed by common bean (50), groundnut (44), pea (32) and mungbean (14). Gamma or x-ray exposures of seeds led to the direct development of 111 cultivars, while neutron and chemical mutagen treatments resulted in 8 and 36 cultivars respectively. One hundred and three cultivars have been developed using mutants in cross breeding. Attempts have been made to estimate the successful dose range for gamma and x-rays, defined as the dose range, which led to the development, registration and release of a maximum number of mutant cultivars. Exposures to seeds ranging between 100-200 Gy in all grain legumes, except faba bean, resulted in 49 out of 111 cultivars being developed as direct mutants. Successful doses reported for faba bean are lower than 100 Gy. Modified crop plant characters are listed. Besides the development of new cultivars, a large number of induced mutants that show altered nodulation pattern have been isolated in grain legumes. Such mutants have made a significant contribution in basic studies on host-symbiont interactions and towards cloning of plant genes related to symbiosis and nitrogen fixation. Their exploitation in breeding programs for enhancing nitrogen fixation is just beginning. Available information on nodulation mutants in grain legume crops is summarised. Mainly, four types of nodulation mutants have been isolated. They show either: no nodulation (nod -), few nodules (nod +/-), ineffective nodulation (Fix-), hypernodulation (nod ++) or hypernodulation even in the presence of otherwise inhibitory nitrate levels (nts). Hypernodulating and nts mutants are of great interest. A soybean cultivar incorporating nts trait has been released in Australia. (author)

  3. Oilseed cultivars developed from induced mutations and mutations altering fatty acid composition

    International Nuclear Information System (INIS)

    Bhatia, C.R.; Nichterlein, K.; Maluszynski, M.

    1999-01-01

    One hundred and sixty-three cultivars of annual oilseed crops, developed using induced mutations, have been officially approved and released for cultivation in 26 countries. The maximum number of cultivars have been released in soybean (58), followed by groundnut (44), sesame (16), linseed (15), rapeseed (14), Indian mustard (8), castorbean (4), white mustard (3) and sunflower (1). The majority (118 of 163) of the cultivars have been developed as direct mutants and 45 of 163 by using the induced mutants in a crossing programme. While in soybean 53 out of 58 cultivars were selected as direct mutants, in groundnut 22 from 44 were developed after hybridization. Eighty-three cultivars were developed directly by exposing seeds to gamma or X-rays. Attempts have been made to infer the successful dose range, defined as the range which led to the development, registration and release of the maximum number of mutant cultivars for gamma and X-rays. The successful dose ranges in Gy for the main oilseed crops are: soybean 100-200, groundnut 150-250, rapeseed 600-800, Indian mustard 700 and sesame 100-200. The main characteristics of the new cultivars, besides higher yield, are altered plant type, early flowering and maturity and oil content. Mutants altering fatty acid composition have been isolated in soybean, rapeseed, sunflower, linseed and minor oil crops. New cultivars having altered fatty acid composition have been released in rapeseed, sunflower and linseed. The latter, previously grown for non-edible oil, has been converted to a new edible oil crop. (author)

  4. Simplifying the detection of MUTYH mutations by high resolution melting analysis

    International Nuclear Information System (INIS)

    López-Villar, Isabel; Martínez-López, Joaquín; Ayala, Rosa; Wesselink, Jan; Morillas, Juan Diego; López, Elena; Marín, José Carlos; Díaz-Tasende, José; González, Sara; Robles, Luis

    2010-01-01

    MUTYH-associated polyposis (MAP) is a disorder caused by bi-allelic germline MUTYH mutation, characterized by multiple colorectal adenomas. In order to identify mutations in MUTYH gene we applied High Resolution Melting (HRM) genotyping. HRM analysis is extensively employed as a scanning method for the detection of heterozygous mutations. Therefore, we applied HRM to show effectiveness in detecting homozygous mutations for these clinically important and frequent patients. In this study, we analyzed phenotype and genotype data from 82 patients, with multiple (>= 10) synchronous (19/82) or metachronous (63/82) adenomas and negative APC study (except one case). Analysis was performed by HRM-PCR and direct sequencing, in order to identify mutations in MUTYH exons 7, 12 and 13, where the most prevalent mutations are located. In monoallelic mutation carriers, we evaluated entire MUTYH gene in search of another possible alteration. HRM-PCR was performed with strict conditions in several rounds: the first one to discriminate the heteroduplex patterns and homoduplex patterns and the next ones, in order to refine and confirm parameters. The genotypes obtained were correlated to phenotypic features (number of adenomas (synchronous or metachronous), colorectal cancer (CRC) and family history). MUTYH germline mutations were found in 15.8% (13/82) of patients. The hot spots, Y179C (exon 7) and G396D (exon 13), were readily identified and other mutations were also detected. Each mutation had a reproducible melting profile by HRM, both heterozygous mutations and homozygous mutations. In our study of 82 patients, biallelic mutation is associated with being a carrier of ≥10 synchronous polyps (p = 0.05) and there is no association between biallelic mutation and CRC (p = 0.39) nor family history (p = 0.63). G338H non-pathogenic polymorphism (exon 12) was found in 23.1% (19/82) of patients. In all cases there was concordance between HRM (first and subsequent rounds) and sequencing

  5. Effects of the umuC36 mutation on ultraviolet-radiation-induced base-change and frameshift mutations in Escherichia coli

    International Nuclear Information System (INIS)

    Kato, T.; Nakano, E.

    1981-01-01

    The effects of the umuC36 mutation on the induction of base-change and frameshift mutations were studied. An active umuC gene was necessary in either the uvr + or uvr - strains of Escherichia coli K12 for UV- and X-ray-induced mutations to His + , ColE and Spc, which are presumably base-change mutations, but it was not essential for ethyl methanesulphonate or N-methyl-N'-nitro-N-nitrosoguanidine-induced His + mutations. In contrast, only 1 out of 13 trp - frameshift mutations examined was UV reversible, and the process of mutagenesis was umuC + -dependent, whereas a potent frameshift mutagen, ICR191, effectively induced Trp + mutations in most of the strains regardless of the umu + or umuC genetic background. These results suggest that base substitutions are a major mutational type derived from the umuC + -dependent pathway of error-prone repair. (orig.)

  6. cDNA sequencing improves the detection of P53 missense mutations in colorectal cancer

    International Nuclear Information System (INIS)

    Szybka, Malgorzata; Kordek, Radzislaw; Zakrzewska, Magdalena; Rieske, Piotr; Pasz-Walczak, Grazyna; Kulczycka-Wojdala, Dominika; Zawlik, Izabela; Stawski, Robert; Jesionek-Kupnicka, Dorota; Liberski, Pawel P

    2009-01-01

    Recently published data showed discrepancies beteween P53 cDNA and DNA sequencing in glioblastomas. We hypothesised that similar discrepancies may be observed in other human cancers. To this end, we analyzed 23 colorectal cancers for P53 mutations and gene expression using both DNA and cDNA sequencing, real-time PCR and immunohistochemistry. We found P53 gene mutations in 16 cases (15 missense and 1 nonsense). Two of the 15 cases with missense mutations showed alterations based only on cDNA, and not DNA sequencing. Moreover, in 6 of the 15 cases with a cDNA mutation those mutations were difficult to detect in the DNA sequencing, so the results of DNA analysis alone could be misinterpreted if the cDNA sequencing results had not also been available. In all those 15 cases, we observed a higher ratio of the mutated to the wild type template by cDNA analysis, but not by the DNA analysis. Interestingly, a similar overexpression of P53 mRNA was present in samples with and without P53 mutations. In terms of colorectal cancer, those discrepancies might be explained under three conditions: 1, overexpression of mutated P53 mRNA in cancer cells as compared with normal cells; 2, a higher content of cells without P53 mutation (normal cells and cells showing K-RAS and/or APC but not P53 mutation) in samples presenting P53 mutation; 3, heterozygous or hemizygous mutations of P53 gene. Additionally, for heterozygous mutations unknown mechanism(s) causing selective overproduction of mutated allele should also be considered. Our data offer new clues for studying discrepancy in P53 cDNA and DNA sequencing analysis

  7. KRAS and BRAF Mutation Detection: Is Immunohistochemistry a Possible Alternative to Molecular Biology in Colorectal Cancer?

    Directory of Open Access Journals (Sweden)

    Nicolas Piton

    2015-01-01

    Full Text Available KRAS genotyping is mandatory in metastatic colorectal cancer treatment prior to undertaking antiepidermal growth factor receptor (EGFR monoclonal antibody therapy. BRAF V600E mutation is often present in colorectal carcinoma with CpG island methylator phenotype and microsatellite instability. Currently, KRAS and BRAF evaluation is based on molecular biology techniques such as SNaPshot or Sanger sequencing. As molecular testing is performed on formalin-fixed paraffin-embedded (FFPE samples, immunodetection would appear to be an attractive alternative for detecting mutations. Thus, our objective was to assess the validity of KRAS and BRAF immunodetection of mutations compared with the genotyping reference method in colorectal adenocarcinoma. KRAS and BRAF genotyping was assessed by SNaPshot. A rabbit anti-human KRAS polyclonal antibody was tested on 33 FFPE colorectal tumor samples with known KRAS status. Additionally, a mouse anti-human BRAF monoclonal antibody was tested on 30 FFPE tumor samples with known BRAF status. KRAS immunostaining demonstrated both poor sensitivity (27% and specificity (64% in detecting KRAS mutation. Conversely, BRAF immunohistochemistry showed perfect sensitivity (100% and specificity (100% in detecting V600E mutation. Although molecular biology remains the reference method for detecting KRAS mutation, immunohistochemistry could be an attractive method for detecting BRAF V600E mutation in colorectal cancer.

  8. KRAS and BRAF Mutation Detection: Is Immunohistochemistry a Possible Alternative to Molecular Biology in Colorectal Cancer?

    Science.gov (United States)

    Borrini, Francesco; Bolognese, Antonio; Lamy, Aude; Sabourin, Jean-Christophe

    2015-01-01

    KRAS genotyping is mandatory in metastatic colorectal cancer treatment prior to undertaking antiepidermal growth factor receptor (EGFR) monoclonal antibody therapy. BRAF V600E mutation is often present in colorectal carcinoma with CpG island methylator phenotype and microsatellite instability. Currently, KRAS and BRAF evaluation is based on molecular biology techniques such as SNaPshot or Sanger sequencing. As molecular testing is performed on formalin-fixed paraffin-embedded (FFPE) samples, immunodetection would appear to be an attractive alternative for detecting mutations. Thus, our objective was to assess the validity of KRAS and BRAF immunodetection of mutations compared with the genotyping reference method in colorectal adenocarcinoma. KRAS and BRAF genotyping was assessed by SNaPshot. A rabbit anti-human KRAS polyclonal antibody was tested on 33 FFPE colorectal tumor samples with known KRAS status. Additionally, a mouse anti-human BRAF monoclonal antibody was tested on 30 FFPE tumor samples with known BRAF status. KRAS immunostaining demonstrated both poor sensitivity (27%) and specificity (64%) in detecting KRAS mutation. Conversely, BRAF immunohistochemistry showed perfect sensitivity (100%) and specificity (100%) in detecting V600E mutation. Although molecular biology remains the reference method for detecting KRAS mutation, immunohistochemistry could be an attractive method for detecting BRAF V600E mutation in colorectal cancer. PMID:25983749

  9. Detection of p53 gene mutations in bronchial biopsy samples of patients with lung cancer

    International Nuclear Information System (INIS)

    Irshad, S.; Nawaz, T.

    2008-01-01

    Lung cancer is the malignant transformation and expansion of lung tissue. It is the most lethal of all cancers worldwide, responsible for 1.2 million deaths annually. The goal of this study was to detect the p53 gene mutations in lung cancer, in local population of Lahore, Pakistan. These mutations were screened in the bronchial biopsy lung cancer tissue samples. For this purpose microtomed tissue sections were collected. Following DNA extraction from tissue sections, the p53 mutations were detected by amplifying Exon 7 (145 bp) and Exon 8 (152 bp) of the p53 gene. PCR then followed by single-strand conformation polymorphism analysis for screening the p53 gene mutations. This results of SSCP were visualized of silver staining. The results showed different banding pattern indicating the presence of mutation. Majority of the mutations were found in Exon 7. Exon 7 of p53 gene may be the mutation hotspot in lung cancer. In lung cancer, the most prevalent mutations of p53 gene are G -> T transversions; other types of insertions and deletions are also expected, however, the exact nature of mutations in presented work could be confirmed by direct sequencing. (author)

  10. Digenic mutations involving both the BSND and GJB2 genes detected in Bartter syndrome type IV.

    Science.gov (United States)

    Wang, Hong-Han; Feng, Yong; Li, Hai-Bo; Wu, Hong; Mei, Ling-Yun; Wang, Xing-Wei; Jiang, Lu; He, Chu-Feng

    2017-01-01

    Bartter syndrome type IV, characterized by salt-losing nephropathies and sensorineural deafness, is caused by mutations of BSND or simultaneous mutations of both CLCNKA and CLCNKB. GJB2 is the primary causative gene for non-syndromic sensorineural deafness and associated with several syndromic sensorineural deafness. Owing to the rarity of Bartter syndrome, only a few mutations have been reported in the abovementioned causative genes. To investigate the underlying mutations in a Chinese patient with Bartter syndrome type IV, genetic analysis of BSND, CLCNKA, CLCNKB and GJB2 were performed by polymerase chain reaction and direct sequencing. Finally, double homozygous mutations c.22C > T (p.Arg8Trp) and c.127G > A (Val43Ile) were detected in exon 1 of BSND. Intriguingly, compound heterozygous mutations c.235delC (p.Leu79CysfsX3) and c.109G > A (p.Val37Ile) were also revealed in exon 2 of GJB2 in the same patient. No pathogenic mutations were found in CLCNKA and CLCNKB. Our results indicated that the homozygous mutation c.22C > T was the key genetic reason for the proband, and a digenic effect of BSND and GJB2 might contributed to sensorineural deafness. To our knowledge, it was the first report showing that the GJB2 gene mutations were detected in Bartter syndrome. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  11. Specificity of mutations induced by carbon ions in budding yeast Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Matuo, Youichirou; Nishijima, Shigehiro; Hase, Yoshihiro; Sakamoto, Ayako; Tanaka, Atsushi; Shimizu, Kikuo

    2006-01-01

    To investigate the nature of mutations induced by accelerated ions in eukaryotic cells, the effects of carbon-ion irradiation were compared with those of γ-ray irradiation in the budding yeast Saccharomyces cerevisiae. The mutational effect and specificity of carbon-ion beams were studied in the URA3 gene of the yeast. Our experiments showed that the carbon ions generated more than 10 times the number of mutations induced by γ-rays, and that the types of base changes induced by carbon ions include transversions (68.7%), transitions (13.7%) and deletions/insertions (17.6%). The transversions were mainly G:C → T:A, and all the transitions were G:C → A:T. In comparison with the surrounding sequence context of mutational base sites, the C residues in the 5'-AC(A/T)-3' sequence were found to be easily changed. Large deletions and duplications were not observed, whereas ion-induced mutations in Arabidopsis thaliana were mainly short deletions and rearrangements. The remarkable feature of yeast mutations induced by carbon ions was that the mutation sites were localized near the linker regions of nucleosomes, whereas mutations induced by γ-ray irradiation were located uniformly throughout the gene

  12. Specificity of mutations induced by carbon ions in budding yeast Saccharomyces cerevisiae

    Energy Technology Data Exchange (ETDEWEB)

    Matuo, Youichirou [Graduate School of Engineering, Osaka University, Yamada-oka 2-1, Suita, Osaka 565-0871 (Japan); Nishijima, Shigehiro [Graduate School of Engineering, Osaka University, Yamada-oka 2-1, Suita, Osaka 565-0871 (Japan); Hase, Yoshihiro [Radiation-Applied Biology Division, Quantum Beam Science Directorate, Japan Atomic Energy Agency (JAEA), Watanuki-machi 1233, Takasaki, Gunma 370-1292 (Japan); Sakamoto, Ayako [Radiation-Applied Biology Division, Quantum Beam Science Directorate, Japan Atomic Energy Agency (JAEA), Watanuki-machi 1233, Takasaki, Gunma 370-1292 (Japan); Tanaka, Atsushi [Radiation-Applied Biology Division, Quantum Beam Science Directorate, Japan Atomic Energy Agency (JAEA), Watanuki-machi 1233, Takasaki, Gunma 370-1292 (Japan); Shimizu, Kikuo [Radioisotope Research Center, Osaka University, Yamada-oka 2-4, Suita, Osaka 565-0871 (Japan)]. E-mail: shimizu@rirc.osaka-u.ac.jp

    2006-12-01

    To investigate the nature of mutations induced by accelerated ions in eukaryotic cells, the effects of carbon-ion irradiation were compared with those of {gamma}-ray irradiation in the budding yeast Saccharomyces cerevisiae. The mutational effect and specificity of carbon-ion beams were studied in the URA3 gene of the yeast. Our experiments showed that the carbon ions generated more than 10 times the number of mutations induced by {gamma}-rays, and that the types of base changes induced by carbon ions include transversions (68.7%), transitions (13.7%) and deletions/insertions (17.6%). The transversions were mainly G:C {sup {yields}} T:A, and all the transitions were G:C {sup {yields}} A:T. In comparison with the surrounding sequence context of mutational base sites, the C residues in the 5'-AC(A/T)-3' sequence were found to be easily changed. Large deletions and duplications were not observed, whereas ion-induced mutations in Arabidopsis thaliana were mainly short deletions and rearrangements. The remarkable feature of yeast mutations induced by carbon ions was that the mutation sites were localized near the linker regions of nucleosomes, whereas mutations induced by {gamma}-ray irradiation were located uniformly throughout the gene.

  13. A Multipoint Method for Detecting Genotyping Errors and Mutations in Sibling-Pair Linkage Data

    OpenAIRE

    Douglas, Julie A.; Boehnke, Michael; Lange, Kenneth

    2000-01-01

    The identification of genes contributing to complex diseases and quantitative traits requires genetic data of high fidelity, because undetected errors and mutations can profoundly affect linkage information. The recent emphasis on the use of the sibling-pair design eliminates or decreases the likelihood of detection of genotyping errors and marker mutations through apparent Mendelian incompatibilities or close double recombinants. In this article, we describe a hidden Markov method for detect...

  14. Biochip-Based Detection of KRAS Mutation in Non-Small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Barbara Ziegler

    2011-11-01

    Full Text Available This study is aimed at evaluating the potential of a biochip assay to sensitively detect KRAS mutation in DNA from non-small cell lung cancer (NSCLC tissue samples. The assay covers 10 mutations in codons 12 and 13 of the KRAS gene, and is based on mutant-enriched PCR followed by reverse-hybridization of biotinylated amplification products to an array of sequence-specific probes immobilized on the tip of a rectangular plastic stick (biochip. Biochip hybridization identified 17 (21% samples to carry a KRAS mutation of which 16 (33% were adenocarcinomas and 1 (3% was a squamous cell carcinoma. All mutations were confirmed by DNA sequencing. Using 10 ng of starting DNA, the biochip assay demonstrated a detection limit of 1% mutant sequence in a background of wild-type DNA. Our results suggest that the biochip assay is a sensitive alternative to protocols currently in use for KRAS mutation testing on limited quantity samples.

  15. Intercellular distribution of mutations induced in oopcytes of Drosophila melanogaster by chemical and physical mutagens

    International Nuclear Information System (INIS)

    Traut, H.

    1979-01-01

    When females of Drosophila melanogaster are treated with chemical or physical mutagens, not only in one but also in both of the two homologous X chromosomes of a given oocyte, a recessive sex-linked lethal mutation may be induced. A method is described that discriminates between such single and double mutations. A theory is developed to show how a comparison betweeen the expected and the observer frequency of double mutations yields an indication of the intercellular distribution (random or nonrandom) of recessive lethal mutations induced by mutagenic agents in oocytes and, consequently, of the distribution (homogenous or nonhomogeneous) of those agents. Three agents were tested: FUdR (12.5, 50.0 and 81.0 μg/ml), mitomycin C (130.0 μg/ml) and x rays (2000 R, 150 kV). After FUdR feeding, no increase in the mutation frequency usually observed in D. melanogaster without mutagenic treatment was obtained (u = 0.13%, namely three single mutations among 2332 chromosomes tested). After mitomycin C feeding 104 single and three double mutations were obtained. All of the 50 mutations observed after x irradiation were single mutations. The results obtained in the mitomycin C and radiation experiments favor the assumption of a random intercellular distribution of recessive lethal mutations induced by these two agents in oocytes of D. melanogaster. Reasons are discussed why for other types of mutagenic agents nonrandom distributions may be observed with our technique

  16. A novel approach to detect KRAS/BRAF mutation for colon cancer: Highly sensitive simultaneous detection of mutations and simple pre-treatment without DNA extraction.

    Science.gov (United States)

    Suzuki, Shun-Ichi; Matsusaka, Satoshi; Hirai, Mitsuharu; Shibata, Harumi; Takagi, Koichi; Mizunuma, Nobuyuki; Hatake, Kiyohiko

    2015-07-01

    It has been reported that colon cancer patients with KRAS and BRAF mutations that lie downstream of epidermal growth factor receptor (EGFR) acquire resistance against therapy with anti‑EGFR antibodies, cetuximab and panitumumab. On the other hand, some reports say KRAS codon 13 mutation (p.G13D) has lower resistance against anti-EGFR antibodies, thus there is a substantial need for detection of specific KRAS mutations. We have established a state-of-the-art measurement system using QProbe (QP) method that allows simultaneous measurement of KRAS codon 12/13, p.G13D and BRAF mutation, and compared this method against Direct Sequencing (DS) using 182 specimens from colon cancer patients. In addition, 32 biopsy specimens were processed with a novel pre-treatment method without DNA purification in order to detect KRAS/BRAF. As a result of KRAS mutation measurement, concordance rate between the QP method and DS method was 81.4% (144/177) except for the 5 specimens that were undeterminable. Among them, 29 specimens became positive with QP method and negative with DS method. BRAF was measured with QP method only, and the mutation detection rate was 3.9% (6/153). KRAS measurement using a simple new pre-treatment method without DNA extraction resulted in 31 good results out of 32, all of them matching with the DS method. We have established a simple but highly sensitive simultaneous detection system for KRAS/BRAF. Moreover, introduction of the novel pre-treatment technology eliminated the inconvenient DNA extraction process. From this research achievement, we not only anticipate quick and accurate results returned in the clinical field but also contribution in improving the test quality and work efficiency.

  17. Use of induced mutations in improving sorghum hybrids

    Energy Technology Data Exchange (ETDEWEB)

    Shashidhar, L S; Patil, S S; Goud, J V [University of Agricultural Sciences, Dharwad (India)

    1990-01-01

    Full text: The established male sterile line '296A' and a restorer line '5501' were mutagenised using 0.05% MMS, and the mutagenised populations were involved in the following cross combinations: 296A x 5501 (M{sub 1} and M{sub 2}), 296A (M{sub 1}) x 5501, 296A (M{sub 1}) x 5501 (M{sub 1}). The derived F{sub 1} populations of these combinations were compared with control F{sub 1} populations with respect to yield/plant. Induced mutations increased combining ability of the restorer parent as evidenced by an increase in the mean of the derived F{sub 1} populations, involving M{sub 1} and M{sub 2} populations of 5501 as males. On the contrary, the mean combining ability of 296A remained unchanged. However, variability in all these derived F{sub 1} populations was increased over that of control F{sub 1} indicating that selection can be practiced for mutants with better combining ability. (author)

  18. Insight on Mutation-Induced Resistance from Molecular Dynamics Simulations of the Native and Mutated CSF-1R and KIT.

    Directory of Open Access Journals (Sweden)

    Priscila Da Silva Figueiredo Celestino Gomes

    Full Text Available The receptors tyrosine kinases (RTKs for the colony stimulating factor-1, CSF-1R, and for the stem cell factor, SCFR or KIT, are important mediators of signal transduction. The abnormal function of these receptors, promoted by gain-of-function mutations, leads to their constitutive activation, associated with cancer or other proliferative diseases. A secondary effect of the mutations is the alteration of receptors' sensitivity to tyrosine kinase inhibitors, compromising effectiveness of these molecules in clinical treatment. In particular, the mutation V560G in KIT increases its sensitivity to Imatinib, while the D816V in KIT, and D802V in CSF-1R, triggers resistance to the drug. We analyzed the Imatinib binding affinity to the native and mutated KIT (mutations V560G, S628N and D816V and CSF-1R (mutation D802V by using molecular dynamics simulations and energy calculations of Imatinib•target complexes. Further, we evaluated the sensitivity of the studied KIT receptors to Imatinib by measuring the inhibition of KIT phosphorylation. Our study showed that (i the binding free energy of Imatinib to the targets is highly correlated with their experimentally measured sensitivity; (ii the electrostatic interactions are a decisive factor affecting the binding energy; (iii the most deleterious impact to the Imatinib sensitivity is promoted by D802V (CSF-1R and D816V (KIT mutations; (iv the role of the juxtamembrane region, JMR, in the imatinib binding is accessory. These findings contribute to a better description of the mutation-induced effects alternating the targets sensitivity to Imatinib.

  19. Induced mutations for disease resistance in wheat and field beans

    International Nuclear Information System (INIS)

    Abdel-Hak, T.M.; Kamel, A.H.

    1976-01-01

    Wheat disease in Egypt is reviewed and results of mutation breeding by γ irradiation for disease resistance in wheat and field beans are described. Wheat mutants of the variety Giza 155 resistant to leaf rust, Giza 156 resistant to both leaf and yellow rusts, and Tosson with a reasonable level of combined resistance to the three rusts in addition to mutants of the tetraploid variety Dakar 52 with a good level of stem and yellow rust resistance are required. Their seeds were subjected to 10, 15 and 20 krad. Of 3000-3700 M 2 plants from each variety and dosage, 22 plants from both Giza 155 and Giza 156, although susceptible, showed a lower level of disease development. In 1975, M 3 families of these selected plants and 6000 plants from bulked material were grown from each variety and dosage at two locations. Simultaneously, an additional population consisting of 3000 mutagen-treated seeds was grown to have a reasonable chance of detecting mutants; 2 heads from each plant were harvested. These will be grown next season (1976) to make a population of 25,000-30,000 M 2 plants and screened to composite cultures of specific rusts. Vicia faba seeds of field bean varieties Giza 1, Giza 2 and Rebaya 40, equally susceptible to rust and chocolate spot, were subjected to 3, 5 and 7 krad of 60 Co gamma radiation and 800 M 1 plants were grown in 1972 per variety and dose. Up to this later growing season (M 3 ) no resistance was detected in M 3 plank

  20. Induced mutation breeding for the improvement of rice in Malaysia

    International Nuclear Information System (INIS)

    Rusli Ibrahim; Abdul Rahim Harun; Ramli Othman; Farazi Johari; Asnah Hassan

    2002-01-01

    The first application of nuclear technology in mutation breeding for the improvement of rice was undertaken by the Malaysian Institute for Nuclear Technology Research (MINT) in December, 1984 for a Coordinated Research Programme under RCA/IAEA/FAO entitled Semi Dwarf Mutants for Rice Improvement in Asia and Pacific. The main objective was to generate semi dwarf mutants in both native and improved cultivars for possible use as new released cultivars or as parents in cross breeding programmes. Within five years, 101 semi dwarf mutants which have the potential to be used as new cultivars or as parents in cross breeding were identified. Twenty nine of the semi dwarf mutants have grain yield between 6000-7300 kg/ha which were classified as potentially good yielding mutants. The parent, Manik yielded about 5700 kg/ha. Forty seven mutants have grain yield between 5000 6000 kg/ha and 25 mutants yielded in the range of 4300-5000 kg/ha. Twelve mutants are resistant to BPH (brown planthopper) but only one, mutant ML15 has grain yield (6300 kg / ha) better than the parent. One of the most striking effects of radiation (gamma ray) was the formation of glutinous rice (Manik 817) with both good yield and head recovery. It is also interesting to note that one of the mutants (MA 03) shows a drastic change in its characteristics and performs better than the parent and other mutant lines. This mutant was late popularly known as mutant Tongkat Ali because of its: outstanding agronomic features such as very erect panicle even after grain filling, very strong culm and resistance to lodging. Even though this mutant was not officially released, due to its unique characteristics and high yield, it has been planted commercially by several farmers especially in the northern parts of Malaysia. More collaborative research programmes using induced mutation breeding have been carried out between MINT, MADA and also MARDI with the aim of producing new potential varieties with high yield, disease

  1. Molecular analysis of carbon ion-induced mutations in Arabidopsis thaliana

    International Nuclear Information System (INIS)

    Shikazono, Naoya; Tanaka, Atsushi; Watanabe, Hiroshi; Tano, Shigemitsu; Yokota, Yukihiko

    1998-01-01

    In order to elucidate the characteristics of the mutations induced by ion particles at the molecular level in plants, mutated loci in carbon ion-induced mutants of Arabidopsis were investigated by PCR and Southern blot analyses. In the present study, two lines of gl1 mutant and two lines of tt4 mutant were isolated after carbon ion-irradiation. Out of four mutants, one had a deletion, other two contained rearrangements, and one had a point-like mutation. From the present result, it was suggested that ion particles induced different kinds of alterations of the DNA and therefore they could produce various types of mutant alleles in plants. (author)

  2. Some results on the combined use of induced mutations and heterosis breeding

    International Nuclear Information System (INIS)

    Stoilov, M.; Daskaloff, S.

    1976-01-01

    The literature on the combined use of induced mutations and heterosis in cultivated species is reviewed. Data from studies of the general and specific combining ability of induced mutations for gene markers both obtained and used in hybrid seed production, translocation lines for development of seedless fruits, male sterile forms, etc., are supplied. The authors give data from their own experimental material for use of mutant lines in heterosis breeding and hybrid seed production. It is concluded that the combined use of induced mutations and heterosis in both self- and cross-pollinating species is very promising. (author)

  3. The Pattern and Distribution of Induced Mutations in J. curcas Using Reduced Representation Sequencing

    Directory of Open Access Journals (Sweden)

    Fatemeh Maghuly

    2018-04-01

    Full Text Available Mutagenesis in combination with Genotyping by Sequencing (GBS is a powerful tool for introducing variation, studying gene function and identifying causal mutations underlying phenotypes of interest in crop plant genomes. About 400 million paired-end reads were obtained from 82 ethylmethane sulfonate (EMS induced mutants and 14 wild-type accessions of Jatropha curcas for the detection of Single Nucleotide Polymorphisms (SNPs and Insertion/Deletions (InDels by two different approaches (nGBS and ddGBS on an Illumina HiSeq 2000 sequencer. Using bioinformatics analyses, 1,452 induced SNPs and InDels were identified in coding regions, which were distributed across 995 genes. The predominantly observed mutations were G/C to A/T transitions (64%, while transversions were observed at a lower frequency (36%. Regarding the effect of mutations on gene function, 18% of the mutations were located in intergenic regions. In fact, mutants with the highest number of heterozygous SNPs were found in samples treated with 0.8% EMS for 3 h. Reconstruction of the metabolic pathways showed that in total 16 SNPs were located in six KEGG pathways by nGBS and two pathways by ddGBS. The most highly represented pathways were ether-lipid metabolism and glycerophospholipid metabolism, followed by starch and sucrose metabolism by nGBS and triterpenoid biosynthesis as well as steroid biosynthesis by ddGBS. Furthermore, high genome methylation was observed in J. curcas, which might help to understand the plasticity of the Jatropha genome in response to environmental factors. At last, the results showed that continuously vegetatively propagated tissue is a fast, efficient and accurate method to dissolve chimeras, especially for long-lived plants like J. curcas. Obtained data showed that allelic variations and in silico analyses of gene functions (gene function prediction, which control important traits, could be identified in mutant populations using nGBS and ddGBS. However, the

  4. Detection of Hepatitis B Virus M204I Mutation by Quantum Dot-Labeled DNA Probe

    Directory of Open Access Journals (Sweden)

    Cheng Zhang

    2017-04-01

    Full Text Available Quantum dots (QDs are semiconductor nanoparticles with a diameter of less than 10 nm, which have been widely used as fluorescent probes in biochemical analysis and vivo imaging because of their excellent optical properties. Sensitive and convenient detection of hepatitis B virus (HBV gene mutations is important in clinical diagnosis. Therefore, we developed a sensitive, low-cost and convenient QDs-mediated fluorescent method for the detection of HBV gene mutations in real serum samples from chronic hepatitis B (CHB patients who had received lamivudine or telbivudine antiviral therapy. We also evaluated the efficiency of this method for the detection of drug-resistant mutations compared with direct sequencing. In CHB, HBV DNA from the serum samples of patients with poor response or virological breakthrough can be hybridized to probes containing the M204I mutation to visualize fluorescence under fluorescence microscopy, where fluorescence intensity is related to the virus load, in our method. At present, the limits of the method used to detect HBV genetic variations by fluorescence quantum dots is 103 IU/mL. These results show that QDs can be used as fluorescent probes to detect viral HBV DNA polymerase gene variation, and is a simple readout system without complex and expensive instruments, which provides an attractive platform for the detection of HBV M204I mutation.

  5. Stamina pistilloida: a new mutation induced in pea.

    Science.gov (United States)

    Monti, L M; Devreux, M

    1969-01-01

    After diethylsulphate treatment of seeds of the pea variety 'Parvus', a new floral mutation was isolated in the second generation. This mutation, named stamina pistilloida, is characterized by a partial fusion of the androecium with the gynoecium; the two marginal stamens of the staminal column are transformed in rudimentary carpels more or less differentiated according to ecoclimatic conditions. The genetic analysis has shown the monogenic and recessive behaviour of the mutation (gene proposed stp) and its linkage with the gene oh in the chromosome II.

  6. A novel fully automated molecular diagnostic system (AMDS for colorectal cancer mutation detection.

    Directory of Open Access Journals (Sweden)

    Shiro Kitano

    Full Text Available BACKGROUND: KRAS, BRAF and PIK3CA mutations are frequently observed in colorectal cancer (CRC. In particular, KRAS mutations are strong predictors for clinical outcomes of EGFR-targeted treatments such as cetuximab and panitumumab in metastatic colorectal cancer (mCRC. For mutation analysis, the current methods are time-consuming, and not readily available to all oncologists and pathologists. We have developed a novel, simple, sensitive and fully automated molecular diagnostic system (AMDS for point of care testing (POCT. Here we report the results of a comparison study between AMDS and direct sequencing (DS in the detection of KRAS, BRAF and PI3KCA somatic mutations. METHODOLOGY/PRINCIPAL FINDING: DNA was extracted from a slice of either frozen (n = 89 or formalin-fixed and paraffin-embedded (FFPE CRC tissue (n = 70, and then used for mutation analysis by AMDS and DS. All mutations (n = 41 among frozen and 27 among FFPE samples detected by DS were also successfully (100% detected by the AMDS. However, 8 frozen and 6 FFPE samples detected as wild-type in the DS analysis were shown as mutants in the AMDS analysis. By cloning-sequencing assays, these discordant samples were confirmed as true mutants. One sample had simultaneous "hot spot" mutations of KRAS and PIK3CA, and cloning assay comfirmed that E542K and E545K were not on the same allele. Genotyping call rates for DS were 100.0% (89/89 and 74.3% (52/70 in frozen and FFPE samples, respectively, for the first attempt; whereas that of AMDS was 100.0% for both sample sets. For automated DNA extraction and mutation detection by AMDS, frozen tissues (n = 41 were successfully detected all mutations within 70 minutes. CONCLUSIONS/SIGNIFICANCE: AMDS has superior sensitivity and accuracy over DS, and is much easier to execute than conventional labor intensive manual mutation analysis. AMDS has great potential for POCT equipment for mutation analysis.

  7. Breeding high yielding varieties of pigeon pea, mungbean and black gram using induced mutations

    International Nuclear Information System (INIS)

    Pawar, S.E.; Wanjari, K.B.

    1994-01-01

    The present communication emphasis the developing of high yielding varieties of pigeon pea, mungbean and black gram using induced mutation with disease resistance in these crops. This would help in stabilisation of the higher yield potential

  8. HPRT gene locus mutation in peripheral blood lymphocytes induced by internal exposure to radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Jingyong, Zhao; Yongzhong, Xu; Tao, Zhao; Fengmei, Cui; Liuyi, Wang; Qinhua, Lao [Suzhou Univ., Suzhou (China). Radiation Medicine Department

    2001-07-01

    HPRT gene locus mutation in peripheral blood lymphocytes induced by internal exposure to radionuclides was performed and the relationships between mutation frequency and dose were studied. Rats were injected intravenously with radionuclides, the blood was sampled at different time after injection; HPRT gene locus mutation frequency (GMF) were examined by methods of multi-nucleus cell and Brdurd assay, working out the Dose-response function. GMF rose with the increase of dose and dose-rates and were clearly interrelated. The HPRT gene locus mutation is very sensitive to radiation and may be used as a biological dosimeter.

  9. Induced mutations for disease resistance in wheat and barley

    International Nuclear Information System (INIS)

    Hanis, M.; Hanisova, A.; Knytl, V.; Cerny, J.; Benc, S.

    1977-01-01

    The induction of mutations in cultivars of wheat (Triticum aestivum), barley (Hordeum vulgare), and field beans (Phaseolus vulgaris) has been part of the breeding programme at the Plant Breeding Station at Stupice since 1960. A total of 26 cultivars or selections of winter wheat, 4 cultivars or selections of spring wheat, 2 cultivars of field beans, and 43 selections of spring barley have been treated since 1960. A total of 140 mutant lines of wheat and 37 mutant lines of barley with improved disease resistance of a race-specific type have been obtained. Several mutation programme derived cultivars have been registered in Czechoslovakia (''Diamant'', ''Ametyst'', ''Favorit'', ''Hana'', ''Rapid'', and ''Atlas'' in barley, and ''Alfa'' in field beans), but none of them is a mutation for disease resistance. A series of mutants have been used in crossing programmes. Approaches to improve the efficiency of mutation breeding for disease resistance are suggested. (author)

  10. Particle-induced chromosome aberrations and mutations: an overview

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, S [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany)

    1997-09-01

    This overview will focus on progress in chromosome and mutation studies achieved by the application of new techniques. Furthermore, recent relevant data on longterm genetic effects of densely ionizing radiation will be summarized. (orig./MG)

  11. Detecting novel genetic mutations in Chinese Usher syndrome families using next-generation sequencing technology.

    Science.gov (United States)

    Qu, Ling-Hui; Jin, Xin; Xu, Hai-Wei; Li, Shi-Ying; Yin, Zheng-Qin

    2015-02-01

    Usher syndrome (USH) is the most common cause of combined blindness and deafness inherited in an autosomal recessive mode. Molecular diagnosis is of great significance in revealing the molecular pathogenesis and aiding the clinical diagnosis of this disease. However, molecular diagnosis remains a challenge due to high phenotypic and genetic heterogeneity in USH. This study explored an approach for detecting disease-causing genetic mutations in candidate genes in five index cases from unrelated USH families based on targeted next-generation sequencing (NGS) technology. Through systematic data analysis using an established bioinformatics pipeline and segregation analysis, 10 pathogenic mutations in the USH disease genes were identified in the five USH families. Six of these mutations were novel: c.4398G > A and EX38-49del in MYO7A, c.988_989delAT in USH1C, c.15104_15105delCA and c.6875_6876insG in USH2A. All novel variations segregated with the disease phenotypes in their respective families and were absent from ethnically matched control individuals. This study expanded the mutation spectrum of USH and revealed the genotype-phenotype relationships of the novel USH mutations in Chinese patients. Moreover, this study proved that targeted NGS is an accurate and effective method for detecting genetic mutations related to USH. The identification of pathogenic mutations is of great significance for elucidating the underlying pathophysiology of USH.

  12. Detection of mutation in isoniazid-resistant Mycobacterium tuberculosis isolates from tuberculosis patients in Belarus

    Directory of Open Access Journals (Sweden)

    Bostanabad S

    2008-01-01

    Full Text Available The aim of this study was to investigate the frequency, location and type of katG mutations in Mycobacterium tuberculosis strains isolated from patients in Belarus. Forty two isoniazid-resistant isolates were identified from sputum of 163 patients with active pulmonary tuberculosis. Drug susceptibility testing was determined by using CDC standard conventional proportional method and BACTEC system. Standard PCR method for detection of isoniazid resistance associated mutations was performed by katG gene amplification and DNA sequencing. Most mutations were found in katG gene codons 315, 316 and 309. Four types of mutations were identified in codon 315: AGC→ACC ( n = 36 85%, AGC→AGG ( n = 1 2.3%, AGC→AAC ( n = 2 4.7%, AGC→GGC ( n = 1 2.3%. One type of mutation was found in codon 316: GGC→AGC ( n = 1841.4%, four types of mutations were detected in codon 309: GGT→GGT ( n = 716.1%, GGT→GCT ( n = 49.2%, GGT→GTC ( n = 36.9%, GGT→GGG ( n = 12.7%. The highest frequency of mutations sharing between primary and secondary infections was found in codon 315.

  13. Sample preparation method for induced mutation on orchid

    International Nuclear Information System (INIS)

    Suhaimi Musa; Sakinah Ariffin

    2005-01-01

    Studies on the induction of mutation in Dendrobium orchid at MINT has produced a number of new orchid mutant cultivars. Tissue culture techniques on orchid seeds and meristem cloning are employed in preparing the samples for the mutation induction. Solid medium based on the Murashige and Skoog (1962) and liquid medium based on Vacin and Went (1949) were found to be suitable in producing protocorm like bodies (PLBs) that are required for the irradiation treatment. (Author)

  14. Development of breeding materials in rice by use of induced mutation

    International Nuclear Information System (INIS)

    Amano, Etsuo

    1988-01-01

    On this 25th Gamma Field Symposium, it may be worth while to review the world situation of mutation breeding, the possibility expected to mutation methods suggested by the ever progressing genetics in rice plant, and some of the activities in the Institute of Radiation Breeding. By the help of a small computer, the key word search analysis of 'Mutation Breeding Newsletter and Mutation Breeding Review' was tried, and the results are included in this review to see the present status. The studies on artificially induced mutation suggested that the possibility of dominant mutation is less. It might be probable that the inactivation of genes is the mechanism of mutation. Still the possibility of using mutation breeding techniques for many genetic characters was suggested. After the experience for 25 years, detailed genetical and fine structure analyses became important. The studies on the expression of mutant phenotypes including molecular genetics will help to develop radiation breeding into an effective means to enrich the genetic resources for breeding. The situation in the world, the genes reported in rice, the possibility to induce useful mutants against environmental stress, the mutation in the protein content in grains, the mutants of storage carbohydrate, the possibility to widen gene resources and so on are reported. (Kako, I.)

  15. Detection of microsatellite instability but not truncating APC mutations in gastric adenocarcinomas in Brazilian patients

    OpenAIRE

    Bevilacqua Roberta A.U.; Corvello Cassandra M.; Duarte Ana Paula; Simpson Andrew J.G.

    2000-01-01

    A crucial role for the adenomatous polyposis colonic (APC) gene in colorectal carcinogenesis has been conclusively established, but, the role of APC in gastric tumors remains controversial. APC mutations have been detected at a relatively high frequency in gastric tumors of Japanese patients, yet such mutations have been reported to be extremely rare in British patients and patients from north-central-Italy. We here report the analysis of 40 primary sporadic gastric adenocarcinomas and 35 pri...

  16. The role of radiation induced mutations in crop Improvement

    International Nuclear Information System (INIS)

    Souframanien, J.

    2017-01-01

    Sudden, heritable changes in the genetic material, DNA, are known as mutations. Selection of naturally occurring mutations in wild, ancestral species helped humans in the domestication and further improvement of today's crop plants. Gregor Mendel in 1865 used several such natural mutants in his experiments with garden pea to formulate the laws of inheritance. The term mutation itself was used for the first time by Hugo de Vries in 1901 in his mutation theory. Plant breeding based on the science of genetics, as practiced over the past 100 years, exploited the available genetic variability in the primary gene pool of crop plants, and sometimes in related species. Primarily, simple selection of desirable offspring and cross breeding were the earlier methods of breeding and this utilized the occurrence of spontaneous mutations. In nature, occurrence of natural variability in the form of spontaneous mutations is extremely low (about 10 -6 ), which can be enhanced several fold (∼10 -3 ) by using ionizing radiations or chemical mutagens

  17. Global impact of induced mutation in plant breeding

    International Nuclear Information System (INIS)

    Bhatia, R.

    2001-01-01

    Sudden, heritable changes in the genetic material, DNA, are known as mutations. Selection of naturally occurring mutations in wild, ancestral species helped humans in the domestication and further improvement of today's crop plants. Although Charles Darwin was unaware in 1859 of variation and mutations in living organisms, his theory of evolution by natural selection assumed variability. Much later, it was established that mutations are the source of biodiversity, and the driving force for evolution. Gregor Mendel in 1865 also used several mutants in his experiments with garden pea to formulate the laws of inheritance. The term mutation itself was used for the first time by Hugo de Vries in 1901 in his mutation theory. Plant breeding based on the science of genetics, as practiced over the past 100 years, exploited the available genetic variability in the primary gene pool of crop plants, and sometimes in related species. This approach enlarged the yield potential of crops several fold. It also a) improved the stability of yield by incorporating resistance to various biotic and abiotic stresses; b) improved quality of the produce; and c) altered the adaptability of crop species, providing opportunities to grow new crops for food security outside their traditional range. Genetically improved seed (or other planting material) is the most significant input for developing sustainable cropping systems for food security and economic growth. Half of the increased productivity of today's crop plants comes from genetic improvements. The other half is contributed by inputs and management practices

  18. The nature of radiation-induced mutations at the white locus of Drosophila melanogaster

    International Nuclear Information System (INIS)

    Pastink, A.; Schalet, A.P.; Vreeken, C.; Eeken, J.C.J.; Paradi, E.

    1987-01-01

    X-ray- and neutron-induced mutations at the white locus of Drosophila melanogaster were used to study the nature of radiation-induced genetic damage. Genetic analysis showed the presence of multi-locus deficiencies in 15 out of 31 X-ray mutants and in 26 out of 35 mutants induced by neutrons. The DNA from 11 X-ray and 4 neutron mutants, which were not multi-locus deficiencies, was analyzed by Southern blot-hybridization. Deletions were observed in 2 X-ray and 1 neutron mutant. In combination with cytogenetic techniques, chromosomal rearrangements affecting the white locus (translocations, inversions, etc.) were identified in 3 X-ray and in 2 neutron mutants. A hot-spot for translocation breakpoints was identified in the left arm of the third chromosome. 5 X-ray mutants, which apparently did not contain large deletions, were subjected to further analysis by the nuclease S1 protection method, after cloning of the white gene. In 4 mutants a small deletion could indeed be detected in this way. Thus it seems that by far the main part of X-ray- and neutron-induced white mutants have arisen through large changes in the white gene, especially deletions. (Auth.)

  19. HaloPlex Targeted Resequencing for Mutation Detection in Clinical Formalin-Fixed, Paraffin-Embedded Tumor Samples.

    Science.gov (United States)

    Moens, Lotte N J; Falk-Sörqvist, Elin; Ljungström, Viktor; Mattsson, Johanna; Sundström, Magnus; La Fleur, Linnéa; Mathot, Lucy; Micke, Patrick; Nilsson, Mats; Botling, Johan

    2015-11-01

    In recent years, the advent of massively parallel next-generation sequencing technologies has enabled substantial advances in the study of human diseases. Combined with targeted DNA enrichment methods, high sequence coverage can be obtained for different genes simultaneously at a reduced cost per sample, creating unique opportunities for clinical cancer diagnostics. However, the formalin-fixed, paraffin-embedded (FFPE) process of tissue samples, routinely used in pathology departments, results in DNA fragmentation and nucleotide modifications that introduce a number of technical challenges for downstream biomolecular analyses. We evaluated the HaloPlex target enrichment system for somatic mutation detection in 80 tissue fractions derived from 20 clinical cancer cases with paired tumor and normal tissue available in both FFPE and fresh-frozen format. Several modifications to the standard method were introduced, including a reduced target fragment length and two strand capturing. We found that FFPE material can be used for HaloPlex-based target enrichment and next-generation sequencing, even when starting from small amounts of DNA. By specifically capturing both strands for each target fragment, we were able to reduce the number of false-positive errors caused by FFPE-induced artifacts and lower the detection limit for somatic mutations. We believe that the HaloPlex method presented here will be broadly applicable as a tool for somatic mutation detection in clinical cancer settings. Copyright © 2015 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

  20. Induced mutation for accelerated domestication: a case study of winged bean (Psophocarpus tetragonolobus (L.) (DC)

    International Nuclear Information System (INIS)

    Klu, G. Y. P.

    2000-01-01

    Induced mutations have the ability to increase the rate of domestication of the many under exploited species of plants that may be potentially useful as source of food, forage and industrial raw materials. The process of domestication has been conditioned by single or major gene mutations. The role of mutagenesis in speeding up domestication, which is species dependent, is outlined in this paper. A case study of the role of induced mutations in the domestication of winged bean (Psophocarpus tetragonobolus) is also presented (au)

  1. Plant cultivars derived from mutation induction or the use of induced mutants in cross breeding

    International Nuclear Information System (INIS)

    Micke, A.; Maluszynski, M.; Donini, B.

    1985-01-01

    Since 1969 we have collected information on cultivated varieties of plants, developed by using induced mutations. Whenever we learn about a cultivar presumably derived from an induced mutant or from use of mutants in crosses. we mail a questionnaire to the breeder. The information gathered in this way is stored in our file on ''Mutant Varieties''. Excerpts are published regularly in the form of a list in the FAO/IAEA Mutation Breeding Newsletter. Our mutant variety list has repeatedly provided a basis for analyses on the value and prospects of mutation breeding

  2. Plant cultivars derived from mutation induction or the use of induced mutants in cross breeding

    Energy Technology Data Exchange (ETDEWEB)

    Micke, A; Maluszynski, M; Donini, B [Joint FAO/IAEA Division, Plant Breeding and Genetics Section, Vienna (Austria)

    1985-05-01

    Since 1969 we have collected information on cultivated varieties of plants, developed by using induced mutations. Whenever we learn about a cultivar presumably derived from an induced mutant or from use of mutants in crosses. we mail a questionnaire to the breeder. The information gathered in this way is stored in our file on ''Mutant Varieties''. Excerpts are published regularly in the form of a list in the FAO/IAEA Mutation Breeding Newsletter. Our mutant variety list has repeatedly provided a basis for analyses on the value and prospects of mutation breeding.

  3. Role of combined use of classical induced mutation breeding and biotechnology in development of new flower colour/form in ornamentals

    International Nuclear Information System (INIS)

    Datta, SK.

    2001-01-01

    In floriculture trade there is always demand and necessity of new and novel ornamental varieties. Flower colour is one of the most important component of novelties. Induced somatic mutation techniques by using ionizing radiations and other mutagens have successfully produced quite a large number of new promising varieties (50 Nos.) in different ornamental (Bougainvillea, Chrysanthemum, Hibiscus, Rose, Tuberose, Lantana depressa etc.) plants by bringing about genetic changes at Floriculture Section, National Botanical Research Institute, India. For inducing novelties in flower colour of different plants the technique of selection of proper type/state of plant material for experiment, suitable dose, detection of mutation at right stage of development, isolation and multiplication of chimeric tissue have been standardised. The capability of the technique is well understood from significant number of new varieties developed via direct mutation breeding in already adapted, modern genotypes and enriched the germplasm. The mutations in flower lour/shape were detected as chimera in M1v1, M1v2, M1v3 generations. The mutation frequency varied with the cultivar and exposure of gamma rays. The main bottleneck of mutation breeding is that the mutation appears as chimera. When the entire branch is mutated, mutants can be isolated through conventional propagation techniques while small sectorial mutation in the floret cannot be isolated using existing conventional techniques. Therefore, many new flower colour/shape mutants are lost due to the lack of a suitable propagation technique. By applying biotechnological technique on the same mutagen treated gamma rays population a novel tissue culture technique hasbeen standardised to regenerate plants directly from such mutated sectors (ray florets) of Chrysanthemum. A number of somatic flower colour/shape mutants have been developed in Chrysanthemum by using this in vitro technique. Combination of classical mutation breeding and

  4. Comparison of behaviors for detection of heritable mutations.

    Science.gov (United States)

    Ficsor, G; Goldner, L; Panda, B B

    1988-01-01

    Groups of five male HA (ICR) mice were injected intraperitoneally with 60, 150, 300, or 600 mg/kg body weight of ethyl methanesulfonate (EMS) or with saline vehicle. Each male was mated to two untreated females at 2 and 5 weeks after treatment. The two successive matings utilized sperm derived from post- and pre-meiotic germ cells, respectively. Progeny were evaluated for litter size, body weight, negative geotactic response, swimming patterns, limb use while swimming, water escape time, and open-field motor coordination activity. Body weight, geotactic response, limb use, and open-field behavior test results demonstrated that EMS causes heritable behavior mutations in both post- and pre-meiotic germ cells. Among the tests that showed inherited differences between control and treated groups, the computer-monitored open-field behavior test was the most definitive.

  5. The use of radiations to induce useful mutations in fruit trees

    International Nuclear Information System (INIS)

    Donini, B.

    1976-01-01

    The researches carried out at Casaccia in this field had covered the problems of technique of mutagenic treatment, mechanism of mutation induction and methodology of somatic mutation isolation. To enhance the efficiency of somatic mutation induction several conditions during and after the treatment have been studied. More experience has been gained with regard to the induction of somatic mutation which raises from genetical event or by tissue arrangement of a chimaeric shoot apex. To increase the size of mutated sector treatment have been carried out on the primordia in a very early stages and to improve the methodology of somatic mutation special techniques have been adapted of handling the material in the propagation. Possibility for early detection of mutants has been explored in cherry by establishing a correlation between mutants and hormonal content. By using the above mentioned techniques, useful mutants have been isolated in cherries, grapes, olives and peaches. (author)

  6. Radiation-induced mutations in sweet cherry (Prunus avium L.)

    Energy Technology Data Exchange (ETDEWEB)

    Saamin, S [Cocoa and Coconut Research Division, Malaysian Agricultural Research and Development Institute (Malaysia); Thompson, M M [Department of Horticulture, Oregon State University, Corvallis, OR (United States)

    1989-01-01

    Full text: Dormant scions of 'Bing' were exposed to 1-2.5 kR gamma radiation. The main buds were excised and the scions grafted to allow the growth of accessory buds into primary shoots. The frequency and types of mutations were described in a population of 3307 M{sub 1}V{sub 2} shoot. The overall mutation frequency was 2.7% incl. 0.15% growth-reduced mutants. The experiment was repeated using 3kR and 4kR fractionated doses in water. Differences in mutation frequency at 3kR and 4kR were not significant. Of 2765 surviving M{sub 1}V{sub 2} shoots derived from irradiation of accessory buds of both standard and V{sub 1} shoots, the overall mutation frequency was 3.3% incl. 1.7% partial leaf mutants, 1.0% leaf mutants, and 0.54% growth-reduced mutants. For maximum mutation rate with adequate survival we suggest acute irradiation of accessory buds in air at dosages approximating LD50. Mutant sectors in M{sub 1}V{sub 1} shoots derived from accessory buds are larger than those from main buds, as revealed by the higher number of mutant repeats. (author)

  7. Detecting coevolving amino acid sites using Bayesian mutational mapping

    DEFF Research Database (Denmark)

    Dimmic, Matthew W.; Hubisz, Melissa J.; Bustamente, Carlos D.

    2005-01-01

    Motivation: The evolution of protein sequences is constrained by complex interactions between amino acid residues. Because harmful substitutions may be compensated for by other substitutions at neighboring sites, residues can coevolve. We describe a Bayesian phylogenetic approach to the detection...

  8. Current study on ionizing radiation-induced mitochondial DNA damage and mutations

    International Nuclear Information System (INIS)

    Zhou Xin; Wang Zhenhua; Zhang Hong

    2012-01-01

    Current advance in ionizing radiation-induced mitochondrial DNA damage and mutations is reviewed, in addition with the essential differences between mtDNA and nDNA damage and mutations. To extent the knowledge about radiation induced mitochondrial alterations, the researchers in Institute of Modern Physics, Chinese Academy of Sciences developed some technics such as real-time PCR, long-PCR for accurate quantification of radiation induced damage and mutations, and in-depth investigation about the functional changes of mitochondria based on mtDNA damage and mutations were also carried out. In conclusion, the important role of mitochondrial study in radiation biology is underlined, and further study on mitochondrial study associated with late effect and metabolism changes in radiation biology is pointed out. (authors)

  9. Phonic and induced level of mutations and mutagenicity in bioorganisms habitating in the environs of Ignalina APP

    International Nuclear Information System (INIS)

    Lekevichius, R.; Morkunas, V.; Knabikas, A.

    1992-01-01

    The investigation of the extracts from the water, mud and hydrobionts of the lake Drukshiai before the construction of the Ignalina atomic power plant (1982-1984) and after its construction enabled to detect the moment of the build-up of mutagens in the hydrobionts (in 1986), when the extracts began to induce spot mutations in Salmonella typhimurium and exchanges of sister chromatids in human leukocytes in vitro. The mutagenicity of rain water, sewerage water and water from the cooler of the atomic power plant to drosophila and Salmonella typhimurium has been detected. The increments of mutations in the populations of Larus ridibundus and Microtus arvalis inhabiting the surroundings of the atomic power plant has not been noticed. (author). 4 figs., 4 refs

  10. Understanding the role of p53 in adaptive response to radiation-induced germline mutations

    International Nuclear Information System (INIS)

    Langlois, N.L.; Quinn, J.S.; Somers, C.M.; Boreham, D.R.; Mitchel, R.E.J.

    2003-01-01

    Full text: Radiation-induced adaptive response is now a widely studied area of radiation biology. Studies have demonstrated reduced levels of radiation-induced biological damage when an 'adaptive dose' is given before a higher 'challenge dose' compared to when the challenge dose is given alone. It has been shown in some systems to be a result of inducible cellular repair systems. The adaptive response has been clearly demonstrated in many model systems, however its impact on heritable effects in the mammalian germline has never been studied. Expanded Simple Tandem Repeat (ESTR) loci have been used as markers demonstrating that induced heritable mutations in mice follow a dose-response relationship. Recent data in our laboratory show preliminary evidence of radiation-induced adaptive response suppressing germline mutations at ESTR loci in wild type mice. The frequency of heritable mutations was significantly reduced when a priming dose of 0.1 Gy was given 24 hours prior to a 1 Gy acute challenging dose. We are now conducting a follow-up study to attempt to understand the mechanism of this adaptive response. P53 is known to play a significant role in governing apoptosis, DNA repair and cancer induction. In order to determine what function p53 has in the adaptive response for heritable mutations, we have mated radiation treated Trp53+/- male mice (C57Bl) to untreated, normal females (C57Bl). Using DNA fingerprinting, we are investigating the rate of inherited radiation-induced mutations on pre- and post-meiotic radiation-treated gametocytes by examining mutation frequencies in offspring DNA. If p53 is integral in the mechanism of adaptive response, we should not see an adaptive response in radiation-induced heritable mutations in these mice. This research is significant in that it will provide insight to understanding the mechanism behind radiation-induced adaptive response in the mammalian germline

  11. DETECTION OF K-RAS AND P53 MUTATIONS IN SPUTUM SAMPLES OF LUNG CANCER PATIENTS USING LASER CAPTURE MICRODISSECTION MICROSCOPE AND MUTATION ANALYSIS

    Science.gov (United States)

    Detection of K-ras and p53 Mutations in Sputum Samples of Lung Cancer Patients Using Laser Capture Microdissection Microscope and Mutation AnalysisPhouthone Keohavong a,*, Wei-Min Gao a, Kui-Cheng Zheng a, Hussam Mady b, Qing Lan c, Mona Melhem b, and Judy Mumford d.<...

  12. The rad2 mutation affects the molecular nature of UV and acridine-mustard-induced mutations in the ADE2 gene of Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Ivanov, E.L.; Kovaltzova, S.V.; Kassinova, G.V.; Gracheva, L.M.; Korolev, V.G.; Zakharov, I.A.

    1986-01-01

    The authors have studied the molecular nature of ade2 mutations induced by UV light and bifunctional acridine-mustard (BAM) in wild-type (RAD) and in excision-deficient (rad2) strains of the yeast, Saccharomyces cerevisiae. In the RAD strain, UV causes 45% GC → AT transitions among all mutations; in the rad2 strain this value is 77%. BAM was shown to be highly specific for frameshift mutagenesis: 60% frameshifts in the RAD strain, and as many as 84% frameshifts in the rad2 strain were induced. Therefore, the rad2 mutation affects the specificity of UV- and BAM-induced mutagenesis in yeast. Experimental data agree with the view that the majority of mutations in the RAD strain are induced by a prereplicative mechanism, whereas mutations in the rad2 strain are predominantly postreplicative events. (Auth.)

  13. Mutation Detection in Patients with Retinal Dystrophies Using Targeted Next Generation Sequencing.

    Directory of Open Access Journals (Sweden)

    Nicole Weisschuh

    Full Text Available Retinal dystrophies (RD constitute a group of blinding diseases that are characterized by clinical variability and pronounced genetic heterogeneity. The different nonsyndromic and syndromic forms of RD can be attributed to mutations in more than 200 genes. Consequently, next generation sequencing (NGS technologies are among the most promising approaches to identify mutations in RD. We screened a large cohort of patients comprising 89 independent cases and families with various subforms of RD applying different NGS platforms. While mutation screening in 50 cases was performed using a RD gene capture panel, 47 cases were analyzed using whole exome sequencing. One family was analyzed using whole genome sequencing. A detection rate of 61% was achieved including mutations in 34 known and two novel RD genes. A total of 69 distinct mutations were identified, including 39 novel mutations. Notably, genetic findings in several families were not consistent with the initial clinical diagnosis. Clinical reassessment resulted in refinement of the clinical diagnosis in some of these families and confirmed the broad clinical spectrum associated with mutations in RD genes.

  14. Multiplex fluorescence melting curve analysis for mutation detection with dual-labeled, self-quenched probes.

    Directory of Open Access Journals (Sweden)

    Qiuying Huang

    2011-04-01

    Full Text Available Probe-based fluorescence melting curve analysis (FMCA is a powerful tool for mutation detection based on melting temperature generated by thermal denaturation of the probe-target hybrid. Nevertheless, the color multiplexing, probe design, and cross-platform compatibility remain to be limited by using existing probe chemistries. We hereby explored two dual-labeled, self-quenched probes, TaqMan and shared-stem molecular beacons, in their ability to conduct FMCA. Both probes could be directly used for FMCA and readily integrated with closed-tube amplicon hybridization under asymmetric PCR conditions. Improved flexibility of FMCA by using these probes was illustrated in three representative applications of FMCA: mutation scanning, mutation identification and mutation genotyping, all of which achieved improved color-multiplexing with easy probe design and versatile probe combination and all were validated with a large number of real clinical samples. The universal cross-platform compatibility of these probes-based FMCA was also demonstrated by a 4-color mutation genotyping assay performed on five different real-time PCR instruments. The dual-labeled, self-quenched probes offered unprecedented combined advantage of enhanced multiplexing, improved flexibility in probe design, and expanded cross-platform compatibility, which would substantially improve FMCA in mutation detection of various applications.

  15. Correlation of oxidative stress in patients with HBV-induced liver disease with HBV genotypes and drug resistance mutations.

    Science.gov (United States)

    Xianyu, Jianbo; Feng, Jiafu; Yang, Yuwei; Tang, Jie; Xie, Gang; Fan, Lingying

    2018-05-01

    This study aims to explore the correlation of oxidative stress (OxS) in patients with chronic hepatitis B (CHB) and the disease severity with HBV genotypes and drug resistance mutations. A total of 296 patients with CHB were enrolled into the study. PCR-reverse dot-blot hybridization was used to detect the HBV genotypes (B, C, and D) and the drug resistance-causing HBV mutant genes. In addition, the total oxidative stress (TOS) and total antioxidant status (TAS) were determined, and oxidative stress index (OSI) was calculated and compared. Serum levels of TOS and OSI, the B/C ratio, and drug resistance mutation rate were increased along with the elevated disease severity degree (CHBHBV mutation had higher serum TOS and OSI levels, while lower serum TAS levels (P HBV-induced liver disease, and the damage degree is correlated with the HBV genotype and drug resistance mutation. Oxidative stress might be a useful indicator of the progression of HBV-induced liver disease in patients. Copyright © 2018. Published by Elsevier Inc.

  16. Induced mutation in dwarf growth habits of apple trees by gamma rays and its evaluation in practical uses

    International Nuclear Information System (INIS)

    Ikeda, Fukio

    1979-01-01

    A series of mutation breeding experiments on apple has been made. The dwarf type mutants having dwarfing rootstock effects on top varieties were developed in the gamma field. In this paper, the induction efficiency that the desirable spur type mutants for top, and the effective dwarf type mutants for rootstocks are produced in a gamma field in comparison with acute irradiation, and some evaluation of the induced mutants for practical purposes are described. A large number of the spur type mutants of apple trees having dwarf growth habit and a desirable tree form for high density planting have been induced by chronic or acute irradiation of gamma-ray since 1962. The mutation with dwarf growth habit including spur types was detected in the grafts on the clonal rootstocks of Marubakaido Malus prunifolia. No useful mutation toward the trees with dwarf growth habit and favorable fruit quality was recognized in the mutants derived from acute irradiation. Chronic treatment has been conducted in the uninjurious area in the gamma field on settled trees. High mutability in the dwarf growth of aged resting buds of settled trees was examined by twice-repeated cutting back treatments. In conclusion, for the induction of useful mutants or effective dwarfing mutants as clonal rootstocks, the artificial mutation breeding with gamma-ray should be conducted under chronic conditions and by planned cutting back treatments, in order to avoid various chromosomal aberrations and intrasomatic selection. (Kato, T.)

  17. Mutator suppression and escape from replication error-induced extinction in yeast.

    Directory of Open Access Journals (Sweden)

    Alan J Herr

    2011-10-01

    Full Text Available Cells rely on a network of conserved pathways to govern DNA replication fidelity. Loss of polymerase proofreading or mismatch repair elevates spontaneous mutation and facilitates cellular adaptation. However, double mutants are inviable, suggesting that extreme mutation rates exceed an error threshold. Here we combine alleles that affect DNA polymerase δ (Pol δ proofreading and mismatch repair to define the maximal error rate in haploid yeast and to characterize genetic suppressors of mutator phenotypes. We show that populations tolerate mutation rates 1,000-fold above wild-type levels but collapse when the rate exceeds 10⁻³ inactivating mutations per gene per cell division. Variants that escape this error-induced extinction (eex rapidly emerge from mutator clones. One-third of the escape mutants result from second-site changes in Pol δ that suppress the proofreading-deficient phenotype, while two-thirds are extragenic. The structural locations of the Pol δ changes suggest multiple antimutator mechanisms. Our studies reveal the transient nature of eukaryotic mutators and show that mutator phenotypes are readily suppressed by genetic adaptation. This has implications for the role of mutator phenotypes in cancer.

  18. The carcinogenic air pollutant 3-nitrobenzanthrone induces GC to TA transversion mutations in human p53 sequences.

    Science.gov (United States)

    vom Brocke, Jochen; Krais, Annette; Whibley, Catherine; Hollstein, Monica C; Schmeiser, Heinz H

    2009-01-01

    3-Nitrobenzanthrone (3-NBA) is a potent mutagen and a suspected human carcinogen present in particulate matter of diesel exhaust and ambient air pollution. Employing an assay with human p53 knock-in (Hupki) murine embryonic fibroblasts (HUFs), we examined p53 mutations induced by 3-NBA and its active metabolite, N-hydroxy-3-aminobenzanthrone (N-OH-3-ABA). Twenty-nine immortalized cultures (cell lines) from 89 HUF primary cultures exposed at passage 1 for 5 days to 2 microM 3-NBA harboured 22 different mutations in the human DNA-binding domain sequence of the Hupki p53 tumour suppressor gene. The most frequently observed mutation was GC to TA transversion (46%), corroborating previous mutation studies with 3-NBA, and consistent with the presence of persistent 3-NBA-guanosine adducts found in DNA of exposed rodents. Six of the transversions found solely in 3-NBA-treated HUFs have not been detected thus far in untreated HUFs, but have been found repeatedly in human lung tumours. (32)P-post-labelling adduct analysis of DNA from HUF cells treated with 2 microM 3-NBA for 5 days showed a pattern similar to that found in vivo, indicating the metabolic competence of HUF cells to metabolize 3-NBA to electrophilic intermediates. Total DNA binding was 160 +/- 56 per 10(7) normal nucleotides with N(2)-guanosine being the major adduct. In contrast, identical treatment with N-OH-3-ABA resulted in a 100-fold lower level of specific DNA adducts and no carcinogen-specific mutation pattern in the Hupki assay. This indicates that the level of DNA adduct formation by the mutagen is critical to obtain specific mutation spectra in the assay. Our results are consistent with previous experiments in Muta Mouse and are compatible with the possibility that diesel exhaust exposure contributes to mutation load in humans and to lung cancer risk.

  19. Somatic mosaicism containing double mutations in PTCH1 revealed by generation of induced pluripotent stem cells from nevoid basal cell carcinoma syndrome.

    Science.gov (United States)

    Ikemoto, Yu; Takayama, Yoshinaga; Fujii, Katsunori; Masuda, Mokuri; Kato, Chise; Hatsuse, Hiromi; Fujitani, Kazuko; Nagao, Kazuaki; Kameyama, Kohzoh; Ikehara, Hajime; Toyoda, Masashi; Umezawa, Akihiro; Miyashita, Toshiyuki

    2017-08-01

    Nevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant disorder characterised by developmental defects and tumorigenesis, such as medulloblastomas and basal cell carcinomas, caused by mutations of the patched-1 ( PTCH1 ) gene. In this article, we seek to demonstrate a mosaicism containing double mutations in PTCH1 in an individual with NBCCS. A de novo germline mutation of PTCH1 (c.272delG) was detected in a 31-year-old woman with NBCCS. Gene analysis of two out of four induced pluripotent stem cell (iPSC) clones established from the patient unexpectedly revealed an additional mutation, c.274delT. Deep sequencing confirmed a low-prevalence somatic mutation (5.5%-15.6% depending on the tissue) identical to the one found in iPSC clones. This is the first case of mosaicism unequivocally demonstrated in NBCCS. Furthermore, the mosaicism is unique in that the patient carries one normal and two mutant alleles. Because these mutations are located in close proximity, reversion error is likely to be involved in this event rather than a spontaneous mutation. In addition, this study indicates that gene analysis of iPSC clones can contribute to the detection of mosaicism containing a minor population carrying a second mutation. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  20. Microarray-based mutation detection and phenotypic characterization in Korean patients with retinitis pigmentosa

    Science.gov (United States)

    Kim, Cinoo; Kim, Kwang Joong; Bok, Jeong; Lee, Eun-Ju; Kim, Dong-Joon; Oh, Ji Hee; Park, Sung Pyo; Shin, Joo Young; Lee, Jong-Young

    2012-01-01

    Purpose To evaluate microarray-based genotyping technology for the detection of mutations responsible for retinitis pigmentosa (RP) and to perform phenotypic characterization of patients with pathogenic mutations. Methods DNA from 336 patients with RP and 360 controls was analyzed using the GoldenGate assay with microbeads containing 95 previously reported disease-associated mutations from 28 RP genes. Mutations identified by microarray-based genotyping were confirmed by direct sequencing. Segregation analysis and phenotypic characterization were performed in patients with mutations. The disease severity was assessed by visual acuity, electroretinography, optical coherence tomography, and kinetic perimetry. Results Ten RP-related mutations of five RP genes (PRP3 pre-mRNA processing factor 3 homolog [PRPF3], rhodopsin [RHO], phosphodiesterase 6B [PDE6B], peripherin 2 [PRPH2], and retinitis pigmentosa 1 [RP1]) were identified in 26 of the 336 patients (7.7%) and in six of the 360 controls (1.7%). The p.H557Y mutation in PDE6B, which was homozygous in four patients and heterozygous in nine patients, was the most frequent mutation (2.5%). Mutation segregation was assessed in four families. Among the patients with missense mutations, the most severe phenotype occurred in patients with p.D984G in RP1; less severe phenotypes occurred in patients with p.R135W in RHO; a relatively moderate phenotype occurred in patients with p.T494M in PRPF3, p.H557Y in PDE6B, or p.W316G in PRPH2; and a mild phenotype was seen in a patient with p.D190N in RHO. Conclusions The results reveal that the GoldenGate assay may not be an efficient method for molecular diagnosis in RP patients with rare mutations, although it has proven to be reliable and efficient for high-throughput genotyping of single-nucleotide polymorphisms. The clinical features varied according to the mutations. Continuous effort to identify novel RP genes and mutations in a population is needed to improve the efficiency and

  1. A new scintillation proximity assay-based approach for the detection of KRAS mutations

    Energy Technology Data Exchange (ETDEWEB)

    Lee, So-Young; Lim, Jae-Cheong; Cho, Eun-Ha; Jung, Sung-Hee [Korea Atomic Energy Research Institute (KAERI), Daejeon (Korea, Republic of). Radioisotope Research Div.

    2016-04-01

    KRAS is very commonly mutated resulting in a constitutively activated protein, which is independent of epidermal growth factor receptor (EGFR) ligand binding and resistant to anti-EGFR therapy. Although KRAS is frequently studied, there is still no uniform standard for detecting of KRAS mutations. In this report, a new scintillation proximity assay-based approach is described that determines the relative affinities of wild-type and mutated KRAS to the anti-KRAS antibody. We performed in vitro experiments using normal human colonic cells (CCD18Co), KRAS wild type (Caco-2) and KRAS mutant (HCT 116) cell lines to determine the relative affinities of wild type or mutated KRAS toward an anti-KRAS monoclonal antibody. The process consists of two primary steps: immunoprecipitation from cell lysate to enrich the KRAS protein and the scintillation proximity assay of the immunoprecipitant to determine the relative affinity against the antibody. A fixed concentration of cell lysates was purified by the immunoprecipitation method. The expressions of the KRAS protein in all cell lines was quantitatively confirmed by western blot analysis. For the scintillation proximity assay, the KRAS standard protein was radiolabeled with {sup 125}I by a simple mixing process in the iodogen tube immediately at room temperature immediately before use. The obtained CPM (count per minute) values of were used to calculate the KRAS concentration using purified KRAS as the standard. The calculated relative affinities of 7 μg of Caco-2 and HCT 116 immunoprecipitants for the anti-KRAS antibody were 77 and 0%, respectively. The newly developed scintillation proximity assay-based strategy determines the relative affinities of wild-type or mutated KRAS towards the anti-KRAS monoclonal antibody. This determination can help distinguish mutated KRAS from the wild type protein. The new SPA based approach for detecting KRAS mutations is applicable to many other cancer-related mutations.

  2. A new scintillation proximity assay-based approach for the detection of KRAS mutations

    International Nuclear Information System (INIS)

    Lee, So-Young; Lim, Jae-Cheong; Cho, Eun-Ha; Jung, Sung-Hee

    2016-01-01

    KRAS is very commonly mutated resulting in a constitutively activated protein, which is independent of epidermal growth factor receptor (EGFR) ligand binding and resistant to anti-EGFR therapy. Although KRAS is frequently studied, there is still no uniform standard for detecting of KRAS mutations. In this report, a new scintillation proximity assay-based approach is described that determines the relative affinities of wild-type and mutated KRAS to the anti-KRAS antibody. We performed in vitro experiments using normal human colonic cells (CCD18Co), KRAS wild type (Caco-2) and KRAS mutant (HCT 116) cell lines to determine the relative affinities of wild type or mutated KRAS toward an anti-KRAS monoclonal antibody. The process consists of two primary steps: immunoprecipitation from cell lysate to enrich the KRAS protein and the scintillation proximity assay of the immunoprecipitant to determine the relative affinity against the antibody. A fixed concentration of cell lysates was purified by the immunoprecipitation method. The expressions of the KRAS protein in all cell lines was quantitatively confirmed by western blot analysis. For the scintillation proximity assay, the KRAS standard protein was radiolabeled with 125 I by a simple mixing process in the iodogen tube immediately at room temperature immediately before use. The obtained CPM (count per minute) values of were used to calculate the KRAS concentration using purified KRAS as the standard. The calculated relative affinities of 7 μg of Caco-2 and HCT 116 immunoprecipitants for the anti-KRAS antibody were 77 and 0%, respectively. The newly developed scintillation proximity assay-based strategy determines the relative affinities of wild-type or mutated KRAS towards the anti-KRAS monoclonal antibody. This determination can help distinguish mutated KRAS from the wild type protein. The new SPA based approach for detecting KRAS mutations is applicable to many other cancer-related mutations.

  3. Chimeric proteins for detection and quantitation of DNA mutations, DNA sequence variations, DNA damage and DNA mismatches

    Science.gov (United States)

    McCutchen-Maloney, Sandra L.

    2002-01-01

    Chimeric proteins having both DNA mutation binding activity and nuclease activity are synthesized by recombinant technology. The proteins are of the general formula A-L-B and B-L-A where A is a peptide having DNA mutation binding activity, L is a linker and B is a peptide having nuclease activity. The chimeric proteins are useful for detection and identification of DNA sequence variations including DNA mutations (including DNA damage and mismatches) by binding to the DNA mutation and cutting the DNA once the DNA mutation is detected.

  4. Thermodynamic framework to assess low abundance DNA mutation detection by hybridization

    Science.gov (United States)

    Willems, Hanny; Jacobs, An; Hadiwikarta, Wahyu Wijaya; Venken, Tom; Valkenborg, Dirk; Van Roy, Nadine; Vandesompele, Jo; Hooyberghs, Jef

    2017-01-01

    The knowledge of genomic DNA variations in patient samples has a high and increasing value for human diagnostics in its broadest sense. Although many methods and sensors to detect or quantify these variations are available or under development, the number of underlying physico-chemical detection principles is limited. One of these principles is the hybridization of sample target DNA versus nucleic acid probes. We introduce a novel thermodynamics approach and develop a framework to exploit the specific detection capabilities of nucleic acid hybridization, using generic principles applicable to any platform. As a case study, we detect point mutations in the KRAS oncogene on a microarray platform. For the given platform and hybridization conditions, we demonstrate the multiplex detection capability of hybridization and assess the detection limit using thermodynamic considerations; DNA containing point mutations in a background of wild type sequences can be identified down to at least 1% relative concentration. In order to show the clinical relevance, the detection capabilities are confirmed on challenging formalin-fixed paraffin-embedded clinical tumor samples. This enzyme-free detection framework contains the accuracy and efficiency to screen for hundreds of mutations in a single run with many potential applications in molecular diagnostics and the field of personalised medicine. PMID:28542229

  5. Sensitive detection of point mutation by electrochemiluminescence and DNA ligase-based assay

    Science.gov (United States)

    Zhou, Huijuan; Wu, Baoyan

    2008-12-01

    The technology of single-base mutation detection plays an increasingly important role in diagnosis and prognosis of genetic-based diseases. Here we reported a new method for the analysis of point mutations in genomic DNA through the integration of allele-specific oligonucleotide ligation assay (OLA) with magnetic beads-based electrochemiluminescence (ECL) detection scheme. In this assay the tris(bipyridine) ruthenium (TBR) labeled probe and the biotinylated probe are designed to perfectly complementary to the mutant target, thus a ligation can be generated between those two probes by Taq DNA Ligase in the presence of mutant target. If there is an allele mismatch, the ligation does not take place. The ligation products are then captured onto streptavidin-coated paramagnetic beads, and detected by measuring the ECL signal of the TBR label. Results showed that the new method held a low detection limit down to 10 fmol and was successfully applied in the identification of point mutations from ASTC-α-1, PANC-1 and normal cell lines in codon 273 of TP53 oncogene. In summary, this method provides a sensitive, cost-effective and easy operation approach for point mutation detection.

  6. Induced mutations to develop sources of resistance to rice blast, Pyricularia grisea Sacc

    International Nuclear Information System (INIS)

    Correa-Victoria, F.J.

    2001-01-01

    Rice blast caused by Pyricularia grisea is the most important disease limiting yields worldwide. The pathogen has many virulent forms or pathotypes, hence durable blast resistance is lacking. Studies on strategy to develop durable blast resistance based on defining the genetic structure of the population, using DNA-fingerprinting, and virulence diversity are described. This strategy is leading to the identification of resistance genes/sources against all isolates within a genetic family of the pathogen. Combinations of genes showing complementary resistance to different genetic families of the fungus exclude any compatible interaction with a blast isolate. Identification of complementary resistance genes is based on detecting those virulence factors whose combinations in individual isolates within the pathogen population have a frequency near zero. Identifying and combining resistance genes to which combinations of corresponding virulence genes are absent in the pathogen population should confer more durable resistance than that previously obtained. The use of induced mutations in the development of resistance was limited, since in most cases single gene changes were responsible for the induced resistance against all the pathogen population. The main objective here is to develop many mutants, each with a gene resistant to just one or a few families of the blast pathogen; and crossing them can accumulate the different resistance genes. A total of 201 Latin American commercial cultivars, including Cuban, Brazilian and Venezuelan were analyzed with different genetic families of the blast pathogen to identify potential sources of resistance to blast and identify complementary resistance sources. Characterization of the resistance of 37 mutants of the Colombian rice cultivar Oryzica 1 was conducted in collaboration with the INEA in Colombia. Results suggested that mutations for resistance to genetic families to which Oryzica 1 is susceptible were induced, although one

  7. Efficient detection of factor IX mutations by denaturing high-performance liquid chromatography in Taiwanese hemophilia B patients, and the identification of two novel mutations

    Directory of Open Access Journals (Sweden)

    Pei-Chin Lin

    2014-04-01

    Full Text Available Hemophilia B (HB is an X-linked recessive disorder characterized by mutations in the clotting factor IX (FIX gene that result in FIX deficiency. Previous studies have shown a wide variation of FIX gene mutations in HB. Although the quality of life in HB has greatly improved mainly because of prophylactic replacement therapy with FIX concentrates, there exists a significant burden on affected families and the medical care system. Accurate detection of FIX gene mutations is critical for genetic counseling and disease prevention in HB. In this study, we used denaturing high-performance liquid chromatography (DHPLC, which has proved to be a highly informative and practical means of detecting mutations, for the molecular diagnosis of our patients with HB. Ten Taiwanese families affected by HB were enrolled. We used the DHPLC technique followed by direct sequencing of suspected segments to detect FIX gene mutations. In all, 11 FIX gene mutations (8 point mutations, 2 small deletions/insertions, and 1 large deletion, including two novel mutations (exon6 c.687–695, del 9 mer and c.460–461, ins T were found. According to the HB pedigrees, 25% and 75% of our patients were defined as familial and sporadic HB cases, respectively. We show that DHPLC is a highly sensitive and cost-effective method for FIX gene analysis and can be used as a convenient system for disease prevention.

  8. Quantum dots immunofluorescence histochemical detection of EGFR gene mutations in the non-small cell lung cancers using mutation-specific antibodies

    Directory of Open Access Journals (Sweden)

    Qu YG

    2014-12-01

    Full Text Available Yan-Gang Qu,1 Qian Zhang,2 Qi Pan,3 Xian-Da Zhao,4 Yan-Hua Huang,2 Fu-Chun Chen,3 Hong-Lei Chen41Department of Pathology, The Central Hospital of Enshi Autonomous Prefecture, Enshi, 2Department of Molecular Pathology, Wuhan Nano Tumor Diagnosis Engineering Research Center, Wuhan, Hubei, People’s Republic of China; 3Department of Thoracosurgery, Traditional Chinese Medical Hospital of Wenling, Wenling, Zhejiang, People’s Republic of China; 4Department of Pathology, School of Basic Medical Science, Wuhan University, Wuhan, Hubei, People’s Republic of ChinaBackground: Epidermal growth factor receptor (EGFR mutation status plays an important role in therapeutic decision making for non-small cell lung cancer (NSCLC patients. Since EGFR mutation-specific antibodies (E746-A750del and L858R have been developed, EGFR mutation detection by immunohistochemistry (IHC is a suitable screening test. On this basis, we want to establish a new screening test, quantum dots immunofluorescence histochemistry (QDs-IHC, to assess EGFR gene mutation in NSCLC tissues, and we compared it to traditional IHC and amplification refractory mutation system (ARMS.Materials and methods: EGFR gene mutations were detected by QDs-IHC, IHC, and ADx-ARMS in 65 cases of NSCLC composed of 55 formalin-fixed, paraffin-embedded specimens and ten pleural effusion cell blocks, including 13 squamous cell carcinomas, two adenosquamous carcinomas, and 50 adenocarcinomas.Results: Positive rates of EGFR gene mutations detected by QDs-IHC, IHC, and ADx-ARMS were 40.0%, 36.9%, and 46.2%, respectively, in 65 cases of NSCLC patients. The sensitivity of QDs-IHC when detecting EGFR mutations, as compared to ADx-ARMS, was 86.7% (26/30; the specificity for both antibodies was 100.0% (26/26. IHC sensitivity was 80.0% (24/30 and the specificity was 92.31% (24/26. When detecting EGFR mutations, QDs-IHC and ADx-ARMS had perfect consistency (κ=0.882; P<0.01. Excellent agreement was observed

  9. Somatic mutations in leafs of tobacco seedlings induced by ionizing radiation and pesticide

    International Nuclear Information System (INIS)

    Shin, H. S.; Kim, J. K.; Song, H. S.; Lee, Y. I.

    2001-01-01

    Somatic mutations induced by the combined treatment of pesticide and ionizing radiation were analyzed in the leaves of tobacco seedlings. The pesticide (1,5 and 10 ppm of parathion) was sprayed directly onto the seedlings. The seedlings, with or without pretreatment of pesticide, were irradiated with 0.1 ∼10 Gy of gamma ray. The difference in the somatic mutation frequencies were not significant among groups treated with different concentration of pesticide. The somatic mutations in tobacco seedlings irradiated with gamma-ray showed a clear dose-response relationship in a range of 0.1 to 10 Gy. However, the combined treatment of pesticide and radiation did not cause any synergistic enhancement in the mutation frequencies. The highest efficiency in the induction of somatic mutations could be obtained by irradiating the seedlings with 5 Gy, 12 hours after 1 ppm of pesticide treatment, or 24 hours after 5 ppm of pesticide treatment

  10. DETECTION OF RECESSIVE MUTATIONS (CVM, BLAD AND RED FACTOR INHOLSTEIN BULLS IN SLOVENIA

    Directory of Open Access Journals (Sweden)

    Betka LOGAR

    2008-07-01

    Full Text Available Detection of recessive mutations that causes complex vertebral malformation (CVM and bovine leukocyte adhesion defi ciency (BLAD in Holstein cattle is especially required for bulls, which are used for artifi cial insemination (A.I.; these enable elimination of carriers from the A.I. programs and therefore prevent transmission of unwanted mutations to a large number of offspring. Some breeders are also interested in the identifi cation of carriers of recessive allele for red and white coat colour (Red factor. Here, we performed genetic tests for detection of mutations associated with CVM, BLAD and Red factor using methods previously reported or modifi ed methods. Analysis of Holstein bulls, which were recommended for A.I in Slovenia in the years 2007 and 2008, revealed four (10 % carriers of CVM, and two (5.4 % carriers of red gene, while all bulls were non-carriers of BLAD.

  11. Detecting BRAF Mutations in Formalin-Fixed Melanoma: Experiences with TwoState-of-the-Art Techniques

    Directory of Open Access Journals (Sweden)

    Nicola L. Schoenewolf

    2012-06-01

    Full Text Available Background: Melanoma is characterized by a high frequency of BRAF mutations. It is unknown if the BRAF mutation status has any predictive value for therapeutic approaches such as angiogenesis inhibition. Patients and Methods: We used 2 methods to analyze the BRAF mutation status in 52 of 62 melanoma patients. Method 1 (mutation-specific real-time PCR specifically detects the most frequent BRAF mutations, V600E and V600K. Method 2 (denaturing gel gradient electrophoresis and direct sequencing identifies any mutations affecting exons 11 and 15. Results: Eighteen BRAF mutations and 15 wild-type mutations were identified with both methods. One tumor had a double mutation (GAA in codon 600. Results of 3 samples were discrepant. Additional mutations (V600M, K601E were detected using method 2. Sixteen DNA samples were analyzable with either method 1 or method 2. There was a significant association between BRAF V600E mutation and survival. Conclusion: Standardized tissue fixation protocols are needed to optimize BRAF mutation analysis in melanoma. For melanoma treatment decisions, the availability of a fast and reliable BRAF V600E screening method may be sufficient. If other BRAF mutations in exons 11 and 15 are found to be of predictive value, a combination of the 2 methods would be useful.

  12. PINK1 heterozygous mutations induce subtle alterations in dopamine-dependent synaptic plasticity

    Science.gov (United States)

    Madeo, G.; Schirinzi, T.; Martella, G.; Latagliata, E.C.; Puglisi, F.; Shen, J.; Valente, E.M.; Federici, M.; Mercuri, N.B.; Puglisi-Allegra, S.; Bonsi, P.; Pisani, A.

    2014-01-01

    Background Homozygous or compound heterozygous mutations in the PTEN-induced kinase 1 (PINK1) gene are causative of autosomal recessive, early onset PD. Single heterozygous mutations have been repeatedly detected in a subset of patients as well as in non-affected subjects, and their significance has long been debated. Several neurophysiological studies from non-manifesting PINK1 heterozygotes have shown the existence of neural plasticity abnormalities, indicating the presence of specific endophenotypic traits in the heterozygous state. Methods In the present study, we performed a functional analysis of corticostriatal synaptic plasticity in heterozygous PINK1 knock-out (PINK1+/−) mice by a multidisciplinary approach. Results We found that, despite a normal motor behavior, repetitive activation of cortical inputs to striatal neurons failed to induce long-term potentiation (LTP), whereas long-term depression (LTD) was normal. Although nigral dopaminergic neurons exhibited normal morphological and electrophysiological properties with normal responses to dopamine receptor activation, we measured a significantly lower dopamine release in the striatum of PINK1+/−, compared to control mice, suggesting that a decrease in stimulus-evoked dopamine overflow acts as a major determinant for the LTP deficit. Accordingly, pharmacological agents capable of increasing the availability of dopamine in the synaptic cleft restored a normal LTP in heterozygous mice. Moreover, MAO-B inhibitors rescued a physiological LTP and a normal dopamine release. Conclusions Our results provide novel evidence for striatal plasticity abnormalities even in the heterozygous disease state. These alterations might be considered an endophenotype to this monogenic form of PD, and a valid tool to characterize early disease stage and design possible disease-modifying therapies. PMID:24167038

  13. Irradiation-induced mutation experiments with eiploid and tetraploid tomato plants

    International Nuclear Information System (INIS)

    Boda, J.

    1979-01-01

    Tomato mutation experiments are described. The tomatoes used in the experiment were the diploid Reziszta and its autotetraploid variety. The experimental plants were exposed to an irradiation of 5000 rsd for 1-2 days, and after transplantation into the gamma field, to chronic irradiation during the whole growing season. The chronic treatment heavily reduced fertility in the generations of tetraploid tomato plants. Recurrent treatment of tetraploid led to further deterioration in fertility. Several berries were formed with few seeds or with no seeds at all. After three irradiations, the chlorophyll mutation frequency increased in the diploid and tetraploid tomato plants. For diploids, treatment applied at the seedling stage gave a lower chlorophyll mutation frequency. With tetraploids the same treatment induced similar chlorophyll mutation frequency. As regards to phenotypic variability of quantitative characteristics in diploid and tetraploid tomatoes, the single and repeated chronic irradiation induced no increase in the variability of properties like flowering time, weight, height etc. (author)

  14. Frequency and spectrum of mutations induced by gamma irradiation in single, double and triple dwarf wheats

    International Nuclear Information System (INIS)

    Dhonukshe, B.L.

    1981-01-01

    Induced mutation studies were carried with three dwarf wheat varieties viz., ''Sonalika'', ''Chhoti Lerma'' and ''Hira'', considered to be single, double and trible dwarfs, respectively. Gamma-rays were used as a source of irradiation. Frequency of chlorophyll mutations were comparatively low and the spectrum was narrow. Chlorophyll mutations were altogether absent in the variety ''Sonalika''. A very wide spectrum of viable mutations affecting stem, leaf, ear growth habit, maturity and fertility characteristics was observed in the M 2 . The cumulative frequency of all the mutants together was quite high, which varied with the varieties. There were varietal differences in the composition and width of the spectrum induced by gamma-rays. The dwarf mutants having desirable leaf and spike characters were isolated in all the three varieties. (author)

  15. Fate of induced mutations in higher plants with special emphasis on sexually reproducing species

    International Nuclear Information System (INIS)

    Cornu, Andre

    1978-01-01

    A mutation induced in a plant somatic cell has to overcome quite many difficulties before being isolated and utilized as a marker in a mutated line. If induced in a meristem, three conditions must be fulfilled for the mutation to be transmitted to the subsequent generation: it must be compatible with normal cell multiplication, it must be located in a cell mass that will provide an inflorescence, and it must be in the sporogenetic layer (t2). Under these conditions, or if it is induced in a gamete or in a zygote, the mutation enters a first cycle of sexual reproduction. Meiosis and the subsequent haploid phase constitute severe screening steps for many chromosome aberrations. Studies on Petunia performed by means of marker genes show that male and female gametic viabilities are drastically impaired by deletions. However, a deficient chromosome can be transmitted when the losss of information is compensated for by homologous information as, for example, diploid gametes from tetraploids or disomic gametes resulting from non-disjunction. If partial or complete sterility, whether sporo- or gametophytic, is avoided, then the mutation can be transmitted to the next generation in heterozygous state. When becoming homozygous, the mutation may have effects such that its use can be most difficult. This is the case when this mutation causes rather early lethality or severe sterility. Thus, in higher plants, one faces several cases of powerful and efficient selection against mutations. On the basis of experiments carried out on Petunia, the per locus mutation rate of practical interest ranges between I and 5/10000M 1 plants. Practical conclusions are drawn about which organ should be treated, which mutagen at what dose should be used according to the scope of the research undertaken [fr

  16. Detection of HIV drug resistance mutations in pregnant women receiving single dose Nevirapine in south India

    Directory of Open Access Journals (Sweden)

    Mini S Jacob

    2011-01-01

    Full Text Available Background: Single dose of Nevirapine to prevent mother to child transmission of HIV is the commonest preventive regimen in resource-limited countries. Objectives: The objective of this study was to detect drug-resistant virus after single dose of Nevirapine (sdNVP provided to delivering HIV seropositive (HIV+ve women and to evaluate the time taken for its decay. Results: Of the 36 consenting HIV+ve pregnant women enrolled into the study, the mean hemoglobin and total lymphocyte counts were 10.8 g/dl and 1843 cells/mm 3 , respectively. Mean CD4 counts in 64% of women was 363 cells/mm 3 and mean viral load for 16/36 women was 28,143 copies/ml of plasma. Nevirapine-resistance mutations were detected in 28% of women at delivery; using OLA (Oligonucleotide Ligation Assay. K103N mutations were seen in 19.4% of women while the Y181C mutation was seen in 5%. Both the mutations were detected in 2.7% of women. Sequential blood samples collected at delivery, 7-10 days, 6 weeks, 4 months, 6 months and one year postpartum showed that 81% of K103N mutations and 66.7% of Y181C mutations were detected at 6 weeks postpartum . Wild-type virus had replaced the mutants by one year postpartum in all women except one. Conclusion : These observations are relevant for future treatment with antiretroviral therapy in these women for their HIV disease.

  17. Molecular analysis of formaldehyde-induced mutations in human lymphoblasts and E. coli

    International Nuclear Information System (INIS)

    Crosby, R.M.; Richardson, K.K.; Craft, T.R.; Benforado, K.B.; Liber, H.L.; Skopek, T.R.

    1988-01-01

    The molecular nature of formaldehyde (HCHO)-induced mutations was studied in both human lymphoblasts and E. coli. Thirty HPRT - human lymphoblast colonies induced by eight repetitive 150 μM HCHO treatments were characterized by Southern blot analysis. Fourteen of these mutants (47%) had visible deletions of some or all of the X-linked HPRT bands, indicating that HCHO can induce large losses of DNA in human lymphoblasts. In E. coli., DNA alterations induced by HCHO were characterized with use of the xanthine guanine phosphoribosyl transferase (gpt) gene as the genetic target. Exposure of E. coli to 4 mM HCHO for 1 hr induced large insertions (41%), large deletions (18%), and point mutations (41%). Dideoxy DNA sequencing revealed that most of the point mutations were transversions at GC base pairs. In contrast, exposure of E. coli to 40 mM HCHO for 1 hr produced 92% point mutations, 62% of which were transitions at a single AT base pair in the gene. Therefore, HCHO is capable of producing different genetic alterations in E. coli at different concentrations, suggesting fundamental differences in the mutagenic mechanisms operating at the two concentrations used. Naked pSV2gpt plasmid DNA was exposed to 3.3 or 10 mM HCHO and transformed into E. coli. Most of the resulting mutations were frameshifts, again suggesting a different mutagenic mechanism

  18. Detection of mutations in genes by specific LNA primers

    DEFF Research Database (Denmark)

    2001-01-01

    acid (LNA). LNA oligomers obey the Watson-Crick base-pairing rules and form duplexes that are significantly more stable than similar duplexes formed by DNA. The "allele-specific" LNA-containing oligonucleotides wherein the LNA nucleotide(s) are found at the 3' position can be extended by means......The present invention relates to a method of detecting variant nucleic acid whose nucleotide sequence differs from one another at a single (or more) position(s). The method uses a set of chimeric oligonucleotides containing DNA monomers and monomers of a novel class of DNA analogues, locked nucleic...

  19. Modification of radiation-induced sex-linked recessive lethal mutation frequency by tocopherol

    International Nuclear Information System (INIS)

    Beckman, C.; Roy, R.M.; Sproule, A.

    1982-01-01

    The present study evaluates the effect of supplementing culture medium with α-tocopherol acetate on the yield of sex-linked recessive lethal mutants induced by X-irradiation in mature sperm of Drosophila. Although tocopherol treatment of males had no impact on the yield of mutations, a drastic reduction in mutation frequency was observed when irradiated males were mated to females raised and subsequently maintained on tocopherol-enriched diet. (orig./MG)

  20. Analysis of chlorophyll mutations induced by γ-rays in barley (hordeum vulgare)

    International Nuclear Information System (INIS)

    Wang Cailian; Shen Mei; Xu Gang; Zhao Kongnan; Chen Qiufang

    1991-06-01

    Thirty varieties of dormant barley seeds were irradiated with 137 Cs γ-rays. Dose-effect relations of chlorophyll mutation frequency in M 2 seedling and differences resulting from cultured types or radiosensitive types were investigated. Experimental results show that the relations between chlorophyll mutation frequency and doses can be fitted by a linear regression equation Y = A + BX. According to analysis of covariance, there is no considerable difference in various cultured types, but the difference of five different radiosensitive types is remarkable. The sensitive and intermediate types need much lower doses than other types to induce maximum chlorophyll mutation

  1. Bibliography. Examples of literature related to the use of induced mutations in cross-breeding

    International Nuclear Information System (INIS)

    Micke, A.

    1976-01-01

    The bibliography contains about 400 references arranged alphabetically under the following 20 headings: Genetic analysis of mutants; Mutant gene combination and interaction; Pleiotropy versus linkage; Genetic background; Heterosis and overdominance; Mutations in heterozygous plants such as vegetatively propagated plants; Mutations in hybrids of self-pollinators; Distant hybridization; Increasing recombination; Alteration in the reproductive system; Alteration of photoperiodic response; Self and cross-incompatibility; Male or female sterility; Adaptability of mutants and mutant hybrids; Mutation induction in cross pollinators; Dwarfing mutant genes in cross-breeding; Protein mutants in cross-breeding; Disease resistant mutants in cross-breeding; Practical cross-breeding programmes using mutants; Spontaneous versus induced genetic diversity

  2. Induced mutations for resistance to powdery mildew in wheat

    International Nuclear Information System (INIS)

    Liu Xueyu

    1990-01-01

    The most serious diseases of wheat in the Yangtze River Valley in China are powdery mildew and scab. Breeding for disease resistance either using conventional methods or through mutation breeding is the best way of controlling these diseases. Mutation breeding may be valuable in obtaining genotypes with resistance or tolerance, or for breaking undesirable linkages involving existing genes for disease resistance. The following commercial varieties were used: Yangmai 3, Ningmai 3 and Ningmai 6. They are high-yielding varieties, but susceptible to powdery mildew. Seeds of these cultivars were treated with gamma-rays. The material was screened in the seedling stage in M 2 in the greenhouse and under field conditions in M 3 -M 4 and later generations. The seedlings were inoculated with a spore suspension of the powdery mildew fungus. The most resistant mutant selected from variety Ningmai 3 was the line 34080 with resistance to races 4, 16 and 20. According to the number of progenies in M 2 , the mutation frequency was 1.2x10 -4 . The other two mutants (34157, 34158) were screened from variety Yangmai 3. Mutant 34157 showed a stable resistance to races 4, 16 and 20; mutant 34158 was resistant to races 4 and 20 but susceptible to race 16. Tracing them back to M 2 progeny, the mutation frequency was 1.0x10 -4 . From electrophoretic analysis of mildew resistant mutant lines of wheat we found that the zymogram of peroxidase in resistant lines 34080 and 34157 was different from their parents and that these lines do not have band 3A

  3. 40 CFR 798.5300 - Detection of gene mutations in somatic cells in culture.

    Science.gov (United States)

    2010-07-01

    ... cells in culture. 798.5300 Section 798.5300 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY....5300 Detection of gene mutations in somatic cells in culture. (a) Purpose. Mammalian cell culture... selected by resistance to ouabain. (2) Description. Cells in suspension or monolayer culture are exposed to...

  4. Ligation-based mutation detection and RCA in surface un-modified OSTE+ polymer microfluidic chambers

    DEFF Research Database (Denmark)

    Saharil, Farizah; Ahlford, Annika; Kuhnemund, Malte

    2013-01-01

    For the first time, we demonstrate DNA mutation detection in surface un-modified polymeric microfluidic chambers without suffering from bubble trapping or bubble formation. Microfluidic devices were manufactured in off-stoichiometry thiol-ene epoxy (OSTE+) polymer using an uncomplicated and rapid...... during bio-operation at elevated temperatures. In contrast, PMMA, PDMS and COP microfluidic devices required specific surface treatment....

  5. Improvement of fragment and primer selection for mutation detection by denaturing gradient gel electrophoresis

    NARCIS (Netherlands)

    Wu, Y; Hayes, VM; Osinga, J; Mulder, IM; Looman, MWG; Buys, CHCM; Hofstra, RMW

    1998-01-01

    Denaturing gradient gel electrophoresis (DGGE) is one of the most powerful methods for mutation detection currently available. For successful application the appropriate selection of PCR fragments and PCR primers is crucial. The sequence of interest should always be within the domain with the lowest

  6. Novel allelic mutations in murine Serca2 induce differential development of squamous cell tumors

    Energy Technology Data Exchange (ETDEWEB)

    Toki, Hideaki; Minowa, Osamu; Inoue, Maki; Motegi, Hiromi; Karashima, Yuko; Ikeda, Ami [Team for Advanced Development and Evaluation of Human Disease Models, Riken BioResource Center (BRC), Tsukuba, Ibaraki (Japan); Kaneda, Hideki [Technology and Development Team for Mouse Phenotype Analysis, Riken BRC, Tsukuba, Ibaraki (Japan); Sakuraba, Yoshiyuki [Mutagenesis and Genomics Team, Riken BRC, Tsukuba, Ibaraki (Japan); Saiki, Yuriko [Department of Molecular Pathology, Tohoku University Graduate School of Medicine, Sendai, Miyagi (Japan); Wakana, Shigeharu [Technology and Development Team for Mouse Phenotype Analysis, Riken BRC, Tsukuba, Ibaraki (Japan); Suzuki, Hiroshi [Department of Biochemistry, Asahikawa Medical University, Asahikawa, Hokkaido (Japan); Gondo, Yoichi [Mutagenesis and Genomics Team, Riken BRC, Tsukuba, Ibaraki (Japan); Shiroishi, Toshihiko [Mammalian Genetics Laboratory, National Institute of Genetics, Mishima, Shizuoka (Japan); Noda, Tetsuo, E-mail: tnoda@jfcr.or.jp [Team for Advanced Development and Evaluation of Human Disease Models, Riken BioResource Center (BRC), Tsukuba, Ibaraki (Japan); Department of Cell Biology, Cancer Institute, The Japanese Foundation for Cancer Research, Tokyo (Japan)

    2016-08-05

    Dominant mutations in the Serca2 gene, which encodes sarco(endo)plasmic reticulum calcium-ATPase, predispose mice to gastrointestinal epithelial carcinoma [1–4] and humans to Darier disease (DD) [14–17]. In this study, we generated mice harboring N-ethyl-N-nitrosourea (ENU)-induced allelic mutations in Serca2: three missense mutations and one nonsense mutation. Mice harboring these Serca2 mutations developed tumors that were categorized as either early onset squamous cell tumors (SCT), with development similar to null-type knockout mice [2,4] (aggressive form; M682, M814), or late onset tumors (mild form; M1049, M1162). Molecular analysis showed no aberration in Serca2 mRNA or protein expression levels in normal esophageal cells of any of the four mutant heterozygotes. There was no loss of heterozygosity at the Serca2 locus in the squamous cell carcinomas in any of the four lines. The effect of each mutation on Ca{sup 2+}-ATPase activity was predicted using atomic-structure models and accumulated mutated protein studies, suggesting that putative complete loss of Serca2 enzymatic activity may lead to early tumor onset, whereas mutations in which Serca2 retains residual enzymatic activity result in late onset. We propose that impaired Serca2 gene product activity has a long-term effect on squamous cell carcinogenesis from onset to the final carcinoma stage through an as-yet unrecognized but common regulatory pathway. -- Highlights: •Novel mutations in murine Serca2 caused early onset or late onset of tumorigenesis. •They also caused higher or lower incidence of Darier Disease phenotype. •3D structure model suggested the former mutations led to severer defect on ATPase. •Driver gene mutations via long-range effect on Ca2+ distributions are suggested.

  7. Clinical analysis of PMS2: mutation detection and avoidance of pseudogenes.

    Science.gov (United States)

    Vaughn, Cecily P; Robles, Jorge; Swensen, Jeffrey J; Miller, Christine E; Lyon, Elaine; Mao, Rong; Bayrak-Toydemir, Pinar; Samowitz, Wade S

    2010-05-01

    Germline mutation detection in PMS2, one of four mismatch repair genes associated with Lynch syndrome, is greatly complicated by the presence of numerous pseudogenes. We used a modification of a long-range PCR method to evaluate PMS2 in 145 clinical samples. This modification avoids potential interference from the pseudogene PMS2CL by utilizing a long-range product spanning exons 11-15, with the forward primer anchored in exon 10, an exon not shared by PMS2CL. Large deletions were identified by MLPA. Pathogenic PMS2 mutations were identified in 22 of 59 patients whose tumors showed isolated loss of PMS2 by immunohistochemistry (IHC), the IHC profile most commonly associated with a germline PMS2 mutation. Three additional patients with pathogenic mutations were identified from 53 samples without IHC data. Thirty-seven percent of the identified mutations were large deletions encompassing one or more exons. In 27 patients whose tumors showed absence of either another protein or combination of proteins, no pathogenic mutations were identified. We conclude that modified long-range PCR can be used to preferentially amplify the PMS2 gene and avoid pseudogene interference, thus providing a clinically useful germline analysis of PMS2. Our data also support the use of IHC screening to direct germline testing of PMS2. (c) 2010 Wiley-Liss, Inc.

  8. Detection of somatic mutations by high-resolution DNA melting (HRM) analysis in multiple cancers.

    Science.gov (United States)

    Gonzalez-Bosquet, Jesus; Calcei, Jacob; Wei, Jun S; Garcia-Closas, Montserrat; Sherman, Mark E; Hewitt, Stephen; Vockley, Joseph; Lissowska, Jolanta; Yang, Hannah P; Khan, Javed; Chanock, Stephen

    2011-01-17

    Identification of somatic mutations in cancer is a major goal for understanding and monitoring the events related to cancer initiation and progression. High resolution melting (HRM) curve analysis represents a fast, post-PCR high-throughput method for scanning somatic sequence alterations in target genes. The aim of this study was to assess the sensitivity and specificity of HRM analysis for tumor mutation screening in a range of tumor samples, which included 216 frozen pediatric small rounded blue-cell tumors as well as 180 paraffin-embedded tumors from breast, endometrial and ovarian cancers (60 of each). HRM analysis was performed in exons of the following candidate genes known to harbor established commonly observed mutations: PIK3CA, ERBB2, KRAS, TP53, EGFR, BRAF, GATA3, and FGFR3. Bi-directional sequencing analysis was used to determine the accuracy of the HRM analysis. For the 39 mutations observed in frozen samples, the sensitivity and specificity of HRM analysis were 97% and 87%, respectively. There were 67 mutation/variants in the paraffin-embedded samples, and the sensitivity and specificity for the HRM analysis were 88% and 80%, respectively. Paraffin-embedded samples require higher quantity of purified DNA for high performance. In summary, HRM analysis is a promising moderate-throughput screening test for mutations among known candidate genomic regions. Although the overall accuracy appears to be better in frozen specimens, somatic alterations were detected in DNA extracted from paraffin-embedded samples.

  9. Detection of somatic mutations by high-resolution DNA melting (HRM analysis in multiple cancers.

    Directory of Open Access Journals (Sweden)

    Jesus Gonzalez-Bosquet

    Full Text Available Identification of somatic mutations in cancer is a major goal for understanding and monitoring the events related to cancer initiation and progression. High resolution melting (HRM curve analysis represents a fast, post-PCR high-throughput method for scanning somatic sequence alterations in target genes. The aim of this study was to assess the sensitivity and specificity of HRM analysis for tumor mutation screening in a range of tumor samples, which included 216 frozen pediatric small rounded blue-cell tumors as well as 180 paraffin-embedded tumors from breast, endometrial and ovarian cancers (60 of each. HRM analysis was performed in exons of the following candidate genes known to harbor established commonly observed mutations: PIK3CA, ERBB2, KRAS, TP53, EGFR, BRAF, GATA3, and FGFR3. Bi-directional sequencing analysis was used to determine the accuracy of the HRM analysis. For the 39 mutations observed in frozen samples, the sensitivity and specificity of HRM analysis were 97% and 87%, respectively. There were 67 mutation/variants in the paraffin-embedded samples, and the sensitivity and specificity for the HRM analysis were 88% and 80%, respectively. Paraffin-embedded samples require higher quantity of purified DNA for high performance. In summary, HRM analysis is a promising moderate-throughput screening test for mutations among known candidate genomic regions. Although the overall accuracy appears to be better in frozen specimens, somatic alterations were detected in DNA extracted from paraffin-embedded samples.

  10. Induced mutation research in plant breeding; Recherche sur les mutations radioinduites en phytogenetique

    Energy Technology Data Exchange (ETDEWEB)

    Briggs, R. W. [Biology Department, Brookhaven National Laboratory, Upton, NY (United States)

    1970-01-15

    The improvement of plants is of great importance to the developing countries. The author briefly describes, with references, recent work on mutation breeding by means of ionizing radiations. The aim of this work is to increase the quantity and quality of plants, e.g. by increasing yield, by developing disease- or insect-resistant varieties, by increasing nutritive value, by improving taste, storage life and appearance. (author) [French] L'amélioration des plantes présente une grande importance pour les pays en voie de développement. L’auteur décrit succinctement, en s'appuyant sur des exemples, certaines recherches récentes en phytogénétique faisant intervenir des mutations radioinduites. L'objet du travail exposé dans le mémoire est d'améliorer quantitativement et qualitativement les plantes, par exemple en augmentant les rendements, en créant des variétés résistant aux maladies et aux insectes, en augmentant la valeur nutritive des produits, ou en améliorant leur goût, leur durée de conservation et leur aspect. (author)

  11. A Comprehensive Strategy for Accurate Mutation Detection of the Highly Homologous PMS2.

    Science.gov (United States)

    Li, Jianli; Dai, Hongzheng; Feng, Yanming; Tang, Jia; Chen, Stella; Tian, Xia; Gorman, Elizabeth; Schmitt, Eric S; Hansen, Terah A A; Wang, Jing; Plon, Sharon E; Zhang, Victor Wei; Wong, Lee-Jun C

    2015-09-01

    Germline mutations in the DNA mismatch repair gene PMS2 underlie the cancer susceptibility syndrome, Lynch syndrome. However, accurate molecular testing of PMS2 is complicated by a large number of highly homologous sequences. To establish a comprehensive approach for mutation detection of PMS2, we have designed a strategy combining targeted capture next-generation sequencing (NGS), multiplex ligation-dependent probe amplification, and long-range PCR followed by NGS to simultaneously detect point mutations and copy number changes of PMS2. Exonic deletions (E2 to E9, E5 to E9, E8, E10, E14, and E1 to E15), duplications (E11 to E12), and a nonsense mutation, p.S22*, were identified. Traditional multiplex ligation-dependent probe amplification and Sanger sequencing approaches cannot differentiate the origin of the exonic deletions in the 3' region when PMS2 and PMS2CL share identical sequences as a result of gene conversion. Our approach allows unambiguous identification of mutations in the active gene with a straightforward long-range-PCR/NGS method. Breakpoint analysis of multiple samples revealed that recurrent exon 14 deletions are mediated by homologous Alu sequences. Our comprehensive approach provides a reliable tool for accurate molecular analysis of genes containing multiple copies of highly homologous sequences and should improve PMS2 molecular analysis for patients with Lynch syndrome. Copyright © 2015 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

  12. Utility of BRAF V600E mutation detection in cytologically indeterminate thyroid nodules

    Directory of Open Access Journals (Sweden)

    Rowe Leslie R

    2006-04-01

    Full Text Available Abstract Background Fine needle aspiration (FNA is widely utilized for evaluation of patients with thyroid nodules. However, approximately 30% are indeterminate for malignancy. Recently, a mutation in the BRAF gene has been reported to be the most common genetic event in papillary thyroid carcinoma (PTC. In this retrospective study, we assessed the utility of BRAF V600E mutation detection for refining indeterminate preoperative cytologic diagnoses in patients with PTC. Methods Archival indeterminate thyroid FNAs and corresponding formalin-fixed, paraffin-embedded (FFPE surgical samples with PTC were identified in our patient files. DNA extracted from slide scape lysates and 5 μm FFPE sections were evaluated for the BRAF V600E mutation using LightCycler PCR and fluorescent melting curve analysis (LCPCR. Amplification products that showed deviation from the wild-type genomic DNA melting peak, discordant FNA and FFPE matched pairs, and all benign control samples, underwent direct DNA sequencing. Results A total of 19 indeterminate thyroid FNAs demonstrating PTC on FFPE surgical samples were included in the study. Using BRAF mutation analysis, the preoperative diagnosis of PTC was confirmed in 3/19 (15.8% FNA samples that could not be conclusively diagnosed on cytology alone. However, 9/19 (47.4% FFPE tissue samples were positive for the V600E mutation. Of the discordant pairs, 5/6 FNAs contained less than 50% tumor cells. Conclusion When used with indeterminate FNA samples, BRAF mutation analysis may be a useful adjunct technique for confirming the diagnosis of malignancy in an otherwise equivocal case. However, overall tumor cell content of some archival FNA smear slides is a limiting factor for mutation detection.

  13. Re-analysis of radiation-induced specific locus mutations in the mouse

    International Nuclear Information System (INIS)

    Abrahamson, S.; Wolff, S.

    1976-01-01

    It is stated that a re-analysis of published data on mouse mutation rates induced by x-and gamma rays suggests that the kinetics of induction can be analysed by fitting that data to a parabolic curve. This is interpreted to mean that a substantial proportion of the induced mutations results from gross chromosomal changes such as deletions, some of which are one-track and some of which are two-track. This analysis is based on the assumption that the shape of the dose curve, which in the female is concave upward, reflects the manner in which the mutations are induced rather than representing a one-track (linear) curve whose shape has been modified by differential repair. (author)

  14. Ancient genes establish stress-induced mutation as a hallmark of cancer.

    Science.gov (United States)

    Cisneros, Luis; Bussey, Kimberly J; Orr, Adam J; Miočević, Milica; Lineweaver, Charles H; Davies, Paul

    2017-01-01

    Cancer is sometimes depicted as a reversion to single cell behavior in cells adapted to live in a multicellular assembly. If this is the case, one would expect that mutation in cancer disrupts functional mechanisms that suppress cell-level traits detrimental to multicellularity. Such mechanisms should have evolved with or after the emergence of multicellularity. This leads to two related, but distinct hypotheses: 1) Somatic mutations in cancer will occur in genes that are younger than the emergence of multicellularity (1000 million years [MY]); and 2) genes that are frequently mutated in cancer and whose mutations are functionally important for the emergence of the cancer phenotype evolved within the past 1000 million years, and thus would exhibit an age distribution that is skewed to younger genes. In order to investigate these hypotheses we estimated the evolutionary ages of all human genes and then studied the probability of mutation and their biological function in relation to their age and genomic location for both normal germline and cancer contexts. We observed that under a model of uniform random mutation across the genome, controlled for gene size, genes less than 500 MY were more frequently mutated in both cases. Paradoxically, causal genes, defined in the COSMIC Cancer Gene Census, were depleted in this age group. When we used functional enrichment analysis to explain this unexpected result we discovered that COSMIC genes with recessive disease phenotypes were enriched for DNA repair and cell cycle control. The non-mutated genes in these pathways are orthologous to those underlying stress-induced mutation in bacteria, which results in the clustering of single nucleotide variations. COSMIC genes were less common in regions where the probability of observing mutational clusters is high, although they are approximately 2-fold more likely to harbor mutational clusters compared to other human genes. Our results suggest this ancient mutational response to

  15. Most ultraviolet irradiation induced mutations in the nematode Caenorhabditis elegans are chromosomal rearrangements

    International Nuclear Information System (INIS)

    Stewart, H.I.; Rosenbluth, R.E.; Baillie, D.L.

    1991-01-01

    In this study the utility of 254-nm ultraviolet light (UV) as a magnetic tool in C.elegans is determined. It is demonstrated that irradiation of adult hermaphrodites provides a simple method for the induction of heritable chromosomal rearrangements. A screening protocol was employed that identifies either recessive lethal mutations in the 40 map unit region balanced by the translocation eT1(III;V), or unc-36(III) duplications. Mutations were recovered in 3% of the chromosomes screened after a dose of 120 J/m 2 . This rate resembles that for 1500 R γ-ray-induced mutations selected in a similar manner. The mutations were classified either as lethals [mapping to Linkage Group (LG)III or LGV] or as putative unc-36 duplications. In contrast to the majority of UV-induced mutations analysed in micro-organisms, a large fraction of the C.elegans UV-induced mutations were found to be not simple intragenic lesions, but deficiencies for more than one adjacent gene or more complex events. Preliminary evidence for this conclusion came from the high frequency of mutations that had a dominant effect causing reduced numbers of adult progeny. Subsequently 6 out of 9 analysed LGV mutations were found to be deficiencies. Other specific rearrangements also identified were: one translocation, sT5(II;III), and two unc-36 duplications, sDp8 and sDp9. It was concluded that UV irradiation can easily be used as an additional tool for the analysis of C.elegans chromosomes, and that C.elegans should prove to be a useful organism in which to study the mechanisms whereby UV acts as a mutagen in cells of complex eukaryotes. (author). 46 refs.; 5 figs.; 4 tabs

  16. Improvement of bambara groundnut production using induced mutations

    Energy Technology Data Exchange (ETDEWEB)

    Amoatey, H M; Klu, G Y.P. [Biotechnology and Nuclear Agricultural Research Inst., Ghana Atomic Energy Commission, Legon (Ghana)

    1997-12-01

    Induction of variation in bambara groundnut using gamma radiation has been tried before. However, no mutants with the desired determinate flowering habit and synchronous pod maturity were obtained. This project is aimed at: conducting a nationwide exploration exercise to collect germplasm of bambara groundnut for agronomic evaluation with respect to flowering and fruiting characteristics and their effects on yield; and, applying the technique of mutation induction to create variability (if this is not found in the germplasm to be collected) from which mutants with determinate flowering and fruiting habit may be selected for use in breeding. 6 refs.

  17. Improvement of bambara groundnut production using induced mutations

    International Nuclear Information System (INIS)

    Amoatey, H.M.; Klu, G.Y.P.

    1997-01-01

    Induction of variation in bambara groundnut using gamma radiation has been tried before. However, no mutants with the desired determinate flowering habit and synchronous pod maturity were obtained. This project is aimed at: conducting a nationwide exploration exercise to collect germplasm of bambara groundnut for agronomic evaluation with respect to flowering and fruiting characteristics and their effects on yield; and, applying the technique of mutation induction to create variability (if this is not found in the germplasm to be collected) from which mutants with determinate flowering and fruiting habit may be selected for use in breeding. 6 refs

  18. High Resolution Melting Analysis for Detecting p53 Gene Mutations in Patients with Non-small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Zhihong CHEN

    2011-10-01

    Full Text Available Background and objective It has been proven that p53 gene was related to many human cancers. The mutations in p53 gene play an important role in carcinogensis and mostly happened in exon 5-8. The aim of this study is to establish a high resolution melting (HRM assay to detect p53 mutations from patients with non-small cell lung cancer (NSCLC, to investigate the characteristics of p53 gene mutations, and to analyze the relationship between p53 mutations and evolution regularity of pathogenesis. Methods p53 mutations in exon 5-8 were detected by HRM assay on DNA insolated from 264 NSCLC samples derived from tumor tissues and 54 control samples from pericancerous pulmonary tissues. The mutation samples by the HRM assay were confirmed by sequencing technique. Samples which were positive by HRM but wild type by sequencing were further confirmed by sub-clone and sequencing. Results No mutation was found in 54 pericancerous pulmonary samples by HRM assay. 104 of the 264 tumor tissues demonstrated mutation curves by HRM assay, 102 samples were confirmed by sequencing, including 95 point mutations and 7 frame shift mutations by insertion or deletion. The mutation rate of p53 gene was 39.4%. The mutation rate from exon 5-8 were 11.7%, 8%, 12.5% and 10.6%, respectively and there was no statistically significant difference between them (P=0.35. p53 mutations were significantly more frequent in males than that in females, but not related to the other clinicopathologic characteristics. Conclusion The results indicate that HRM is a sensitive in-tube methodology to detect for mutations in clinical samples. The results suggest that the arising p53 mutations in NSCLC may be due to spontaneous error in DNA synthesis and repair.

  19. Gamma-ray-induced dominant mutations that cause skeletal abnormalities in mice

    International Nuclear Information System (INIS)

    Selby, P.B.; Selby, P.R.

    1977-01-01

    Male mice were exposed to 100 R + 500 R γ-rays (60 R/min) with a 24-h fractionation interval. Skeletons of F 1 sons were examined for abnormalities, and, if any were found, the skeletons of their descendants were also examined. Of 2646 sons from treated spermatogonia, 37, or 1.4%, were diagnosed as carriers of autosomal dominant mutations affecting the skeleton, 31 by breeding tests, and six by other criteria for identifying mutations in F 1 's having no progeny. Many mutations caused a large number of anomalies in different regions of the skeleton. Most regions of the skeleton were affected by at least one mutation, and the mutations had incomplete penetrance for some or all of their effects. Three of the mutations affected skeletal size only. If certain assumptions are made, these skeletal data can be used to derive an estimate of induced genetic damage from dominant mutations affecting all parts of the body. When applied to man, the resultant risk estimate is not inconsistent with that made for dominant and irregularly inherited diseases by the BEIR Committee, by use of the doubling-dose method. Since most of the mutations can be characterized as models of irregularly inherited conditions in man, the data directly relate to the controversy over the relative importance of mutation pressure and balanced selection in maintaining man's large burden of irregularly inherited disease. Contrary to a recent hypothesis by H.B. Newcombe that man's large burden of irregularly inherited disease is maintained almost exclusively by balanced selection, these results suggest that at least an important fraction of the irregularly inherited conditions are maintained by mutation pressure. Therefore, this finding does not support the major changes in the estimate of genetic hazard to man that would be required on the basis of Newcombe's hypothesis

  20. Use of ionizing radiation induced mutation in the genetic development of plants

    International Nuclear Information System (INIS)

    Barragan, Raul; Rubio, Santiago

    1993-01-01

    The objective of this article is to present a general focus on the use of induced mutations in the improvement of plants. This article describes some basic aspects that must be well known by the breeder that hopes to incorporate in his programm the technique of induced mutation by radiations. In this paper are included the results of two trials done by the researchers of the department of plant breeding so that it can be used as reference to determinate the importance of this technique

  1. Deletion mutations of bacteriophage

    International Nuclear Information System (INIS)

    Ryo, Yeikou

    1975-01-01

    Resolution of mutation mechanism with structural changes of DNA was discussed through the studies using bacteriophage lambda. One of deletion mutations inductions of phage lambda is the irradiation of ultraviolet ray. It is not clear if the inductions are caused by errors in reparation of ultraviolet-induced damage or by the activation of int gene. Because the effective site of int gene lies within the regions unnecessary for existing, it is considered that int gene is connected to deletion mutations induction. A certain system using prophage complementarity enables to detect deletion mutations at essential hereditary sites and to solve the relations of deletion mutations with other recombination system, DNA reproduction and repairment system. Duplication and multiplication of hereditary elements were discussed. If lambda deletion mutations of the system, which can control recombination, reproduction and repairment of added DNA, are constructed, mutations mechanism with great changes of DNA structure can be solved by phage lambda. (Ichikawa, K.)

  2. Detection of resistance mutations and CD4 slopes in individuals experiencing sustained virological failure

    DEFF Research Database (Denmark)

    Schultze, Anna; Paredes, Roger; Sabin, Caroline

    2014-01-01

    during the episode were included. Mutations were identified using the IAS-US (2013) list, and were presumed to be present from detection until the end of an episode. Multivariable linear mixed models with a random intercept and slope adjusted for age, baseline CD4 count, hepatitis C, drug type, RNA (log...... mutations on CD4 slopes in patients undergoing episodes of viral failure. MATERIALS AND METHODS: Patients from the EuroSIDA and UK CHIC cohorts undergoing at least one episode of virological failure (>3 consecutive RNA measurements >500 on ART) with at least three CD4 measurements and a resistance test......-scale), risk group and subtype were used to estimate CD4 slopes. Individual mutations with a population prevalence of >10% were tested for their effect on the CD4 slope. RESULTS: A total of 2731 patients experiencing a median of 1 (range 1-4) episodes were included in this analysis. The prevalence of any...

  3. Mutations detected in the repetitive sequences in the children of the atomic bomb survivors

    International Nuclear Information System (INIS)

    Satoh, Chiyoko; Kodaira, Mieko

    1994-01-01

    We have been examining genetic effects of radiation in the children of the atomic bomb survivors. In a pilot study, 50 exposed families with 64 children and 50 control families with 60 children were examined for trinucleotide repeat expansion mutations at 3 loci and mutations at 6 minisatellite loci. Average dose of the 51 exposed parents was 1.8 Sv. By examining 124 children of 100 families, 65 germ cells derived from exposed parents and 183 germ cells of non-exposed parents were examined. The trinucleotide repeat expansions in genes of certain human genetic diseases show remarkable variation both within the cells of a single individual and among affected members of a single family which have been interpreted as mitotic and meiotic instability. We examined the regions with triplet repeats in the FMR-1, AR and DM genes causative for fragile X syndrome, spinobulbar muscular atrophy and myotonic dystrophy. No mutations were detected in 177 regions derived from 65 germ cells of exposed parents and 443 regions from 183 germ cells of non-exposed parents. No effects on the instability of the triplet repeats in the germ cells derived from exposed or unexposed individuals were observed. In the examinations of the 6 minisatellite loci of Pc-1, λTM-18, ChdTC-15, pλg3, λMS-1, and CEB-1, we detected single mutations at each of the pλg3 and λMS-1, and 4 mutations at the CEB-1 locus which had occurred in the 65 gametes in the exposed parents. Thus, mutation rates per gamete at the pλg3, λMS-1 and CEB-1 were 1.5%, 1.5% and 6.2%. On the other hand, mutations in these 3 loci in the 183 gametes of non-exposed parents were 0, 11 and 11, that is, the mutation rates per gamete were 0%, 6.0% and 6.0%. No significant difference was observed in the mutation rate at each of the 3 loci between 2 groups of parents. These preliminary results suggest that A-bomb exposure seems not to affect the germline instability at these 3 loci. (J.P.N)

  4. Effects of a chromosome-3 mutator gene on radiation-induced mutability in Drosophila melanogaster females

    Energy Technology Data Exchange (ETDEWEB)

    Sankaranarayanan, K. (Rijksuniversiteit Leiden (Netherlands). Dept. of Radiation Genetics and Chemical Mutagenesis; Cohen (J.A.) Inst. voor Radiopathologie en Stralenbescherming, Leiden (Netherlands))

    1982-01-01

    A series of X-irradiation experiments was carried out using Drosophila melanogaster females homozygous for a third chromosome mutator gene and females which had a similar genetic background except that the mutator-bearing third chromosomes were substituted by normal wild-type chromosomes. In the present work, the sensitivity of the pre-meiotic germ cells of mutator and normal females to the X-ray induction (2000 R) of sex-linked recessive lethals was studied. In addition, experiments were conducted to examine the sensitivity of the immature (stage 7; prophase I of meiosis) oocytes of both kinds of females to the induction of dominant lethals, X-linked recessive lethals and X-chromosome losses. The results show that in pre-meiotic germ cells, the frequencies of radiation-induced recessive lethals are similar in both kinds of females. However, the proportion of these mutations that occur in clusters of size 3 and higher, is higher in mutator than in normal females. In stage-7 oocytes, the frequencies of radiation-induced dominant lethals and sex-linked recessive lethals were similar in both kinds of females. The X-loss frequencies however, were consistently higher in mutator females although statistical significance was obtained only at higher exposures (3000 and 3750 R) and not at lower ones (750-2250 R). Possible reasons for the discrepancy between the present results and those of Gold and Green with respect to pre-meiotic germ cells are discussed.

  5. Reversal or protection by light of the ethidium bromide induced petite mutation in yeast

    International Nuclear Information System (INIS)

    Hixon, S.C.; Burnham, A.D.; Irons, R.L.

    1979-01-01

    An intermediate in the ethidium bromide (EB) induced petite mutation pathway may be destabilized by daylight light to cause a reversion to the normal grande phenotype. Starved cells preincubated in the dark for up to 6 h with 100μg/ml EB could be reverted to grandes after one hour of light exposure, whereas similarly treated cells maintained in the dark expresse the petite mutation in more than 80 percent of the population. In addition, the production of petite mutants by EB in buffer could be prevented if cell suspensions were exposed to light immediately upon the addition of EB. Photoreversal of the EB-derived petite mutation in growing cells as less efficient presumably because the availability of an energy source caused a continuation of mutation events beyond the light revertible step to a non-reversible fixation of the mutation. Cells treated with EB in growth and reversal of the mutation. This may be due to the cold inhibition of an enzyme which comes into play beyond the light sensitive step in the mutation pathway. (orig.) [de

  6. Efficient Detection of Copy Number Mutations in PMS2 Exons with a Close Homolog.

    Science.gov (United States)

    Herman, Daniel S; Smith, Christina; Liu, Chang; Vaughn, Cecily P; Palaniappan, Selvi; Pritchard, Colin C; Shirts, Brian H

    2018-07-01

    Detection of 3' PMS2 copy-number mutations that cause Lynch syndrome is difficult because of highly homologous pseudogenes. To improve the accuracy and efficiency of clinical screening for these mutations, we developed a new method to analyze standard capture-based, next-generation sequencing data to identify deletions and duplications in PMS2 exons 9 to 15. The approach captures sequences using PMS2 targets, maps sequences randomly among regions with equal mapping quality, counts reads aligned to homologous exons and introns, and flags read count ratios outside of empirically derived reference ranges. The method was trained on 1352 samples, including 8 known positives, and tested on 719 samples, including 17 known positives. Clinical implementation of the first version of this method detected new mutations in the training (N = 7) and test (N = 2) sets that had not been identified by our initial clinical testing pipeline. The described final method showed complete sensitivity in both sample sets and false-positive rates of 5% (training) and 7% (test), dramatically decreasing the number of cases needing additional mutation evaluation. This approach leveraged the differences between gene and pseudogene to distinguish between PMS2 and PMS2CL copy-number mutations. These methods enable efficient and sensitive Lynch syndrome screening for 3' PMS2 copy-number mutations and may be applied similarly to other genomic regions with highly homologous pseudogenes. Copyright © 2018 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

  7. Induction of spontaneous and UV-induced mutations during commitment to meiosis in Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Machida, I.; Nakai, S.

    1980-01-01

    Inductions of reversions of nonsense, missense and frameshift-type mutations were investigated in a diploid cell population of Saccharomyces cerevisiae during commitment to meiosis, by using the medium-transfer technique from sporulation medium to vegetative medium. The yields of spontaneous reverse mutations obtained from the cells that were committed to different stages during meiosis were rather constant irrespective of the alleles tested, although the yields of both intergenic and intragenic recombinations markedly increased. The susceptibilities to UV-induced reverse mutations examined during commitment to meiosis were not changed appreciably. It is concluded that induction of base-change-type mutations in meiosis is not essentially different from that in mitosis. (orig.)

  8. Multi-walled carbon nanotubes (NM401) induce ROS-mediated HPRT mutations in Chinese hamster lung fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Rubio, Laura [Grup de Mutagènesi, Departament de Genètica i de Microbiologia, Facultat de Biociències, Universitat Autònoma de Barcelona, Bellaterra (Spain); El Yamani, Naouale [Health Effects Laboratory-MILK, NILU-Norwegian Institute for Air Research, Kjeller (Norway); Kazimirova, Alena [Department of Biology, Slovak Medical University, Bratislava (Slovakia); Dusinska, Maria, E-mail: maria.dusinska@nilu.no [Health Effects Laboratory-MILK, NILU-Norwegian Institute for Air Research, Kjeller (Norway); Marcos, Ricard, E-mail: ricard.marcos@uab.es [Grup de Mutagènesi, Departament de Genètica i de Microbiologia, Facultat de Biociències, Universitat Autònoma de Barcelona, Bellaterra (Spain); CIBER Epidemiología y Salud Pública, Instituto de Salud Carlos III, Madrid (Spain)

    2016-04-15

    Although there is an important set of data showing potential genotoxic effects of nanomaterials (NMs) at the DNA (comet assay) and chromosome (micronucleus test) levels, few studies have been conducted to analyze their potential mutagenic effects at gene level. We have determined the ability of multi-walled carbon nanotubes (MWCNT, NM401), to induce mutations in the HPRT gene in Chinese hamster lung (V79) fibroblasts. NM401, characterized in the EU NanoGenotox project, were further studied within the EU Framework Programme Seven (FP7) project NANoREG. From the proliferation assay data we selected a dose-range of 0.12 to 12 µg/cm{sup 2} At these range we have been able to observe significant cellular uptake of MWCNT by using transmission electron microscopy (TEM), as well as a concentration-dependent induction of intracellular reactive oxygen species. In addition, a clear concentration-dependent increase in the induction of HPRT mutations was also observed. Data support a potential genotoxic/ carcinogenic risk associated with MWCNT exposure. - Highlights: • MWCNT were tested in V79 cells. • Cellular uptake of MWCNT was detected using TEM. • Intracellular ROS induction was observed after MWCNT exposure. • MWCNT induced a concentration-dependent increase of HPRT mutations.

  9. Multi-walled carbon nanotubes (NM401) induce ROS-mediated HPRT mutations in Chinese hamster lung fibroblasts

    International Nuclear Information System (INIS)

    Rubio, Laura; El Yamani, Naouale; Kazimirova, Alena; Dusinska, Maria; Marcos, Ricard

    2016-01-01

    Although there is an important set of data showing potential genotoxic effects of nanomaterials (NMs) at the DNA (comet assay) and chromosome (micronucleus test) levels, few studies have been conducted to analyze their potential mutagenic effects at gene level. We have determined the ability of multi-walled carbon nanotubes (MWCNT, NM401), to induce mutations in the HPRT gene in Chinese hamster lung (V79) fibroblasts. NM401, characterized in the EU NanoGenotox project, were further studied within the EU Framework Programme Seven (FP7) project NANoREG. From the proliferation assay data we selected a dose-range of 0.12 to 12 µg/cm 2 At these range we have been able to observe significant cellular uptake of MWCNT by using transmission electron microscopy (TEM), as well as a concentration-dependent induction of intracellular reactive oxygen species. In addition, a clear concentration-dependent increase in the induction of HPRT mutations was also observed. Data support a potential genotoxic/ carcinogenic risk associated with MWCNT exposure. - Highlights: • MWCNT were tested in V79 cells. • Cellular uptake of MWCNT was detected using TEM. • Intracellular ROS induction was observed after MWCNT exposure. • MWCNT induced a concentration-dependent increase of HPRT mutations.

  10. Genetic improvement of rice (oryza sativa l.) by induced mutations

    International Nuclear Information System (INIS)

    Suarez, E.; Deus, J. E.; Perez, R.; Alfonso, R.; Hernandez, R.; Avila, J.; Hernandez, J. L.; Puldon, Violeta; Duany, A.; Reinoso, J.; Mesa, H.; Rodriguez, S.

    2001-01-01

    In 1989 was initiated at Rice Research Institute of Cuba, a mutation breeding programme, in order to obtain new germoplasm with improved characters such as milling quality, earliness, resistance to the Hoja Blanca virus disease and salt tolerance. Seven varieties has been irradiated and two different sources of radiation were used: gamma rays from 60Co and fast neutrons of a 14 MeV neutron generator. In 1995, was released the variety IACuba 23 for low inputs conditions. Another four varieties IACuba 21, IACuba 22, IACuba 27 and IACuba 28 are in validation trials in rice production areas under irrigated condition. The last two have showed resistance to Steneotarsonemus spinki. Also, a group of mutants was selected to be used as parents. These mutants have been used in 953 crosses

  11. Induced mutations in Iraqi bread wheat cv. Saber Beg

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, I F; Haidar, H O [Department of Plant Protection, Faculty of Agriculture and Biology, NRC and Agriculture Research Station, Telafor (Iraq)

    1989-07-01

    ''Saber Beg'', is a local wheat cultivar important in the semi-arid zone of Iraq where the rainfall is less than 450 mm per year. This cultivar has a good baking quality, but is of low productivity, high susceptibility to common bunt (Tilletia spp.) and to leaf rust (Puccinia recondita Rob. ex Desm.), but only in the rainy season. A mutation breeding programme using gamma irradiation has been started in 1978 to improve this cultivar. Seeds of all main tillers from M{sub 1} plants were harvested and artificially inoculated with teliospores of Tilletia spp. All the seeds from healthy M{sub 2} plants were inoculated again and sown in the same area. Out of 22920 M{sub 3} plants, 244 resistant ones were selected. During subsequent screening for 4 generations, however, only 3 mutants were confirmed.

  12. Improvement of quinoa and barley through induced mutations and biotechnology

    International Nuclear Information System (INIS)

    Siles, A.Z.; Miranda, L.S.

    2001-01-01

    The main cropping problems in the Bolivian highlands are the long growing period of barley, high degree of environmental influence on the performance of quinoa, and low soil moisture at sowing time, leading to low germination rate and poor stands, and frost or chilling damages. The program aimed to establish protocols for induction of mutations with X rays and chemical mutagens (NaN 3 , MNH, EMS) in quinoa, barley, native forage species and forest plants and to obtain mutant lines, especially in barley and quinoa; and to establish callus regeneration in quinoa and micropropagation of kenua (Polilepis). The project is still in its study stages, hence further evaluations are needed before firm conclusions are drawn. (author)

  13. Induced mutations in Iraqi bread wheat cv. Saber Beg

    International Nuclear Information System (INIS)

    Ibrahim, I.F.; Haidar, H.O.

    1989-01-01

    ''Saber Beg'', is a local wheat cultivar important in the semi-arid zone of Iraq where the rainfall is less than 450 mm per year. This cultivar has a good baking quality, but is of low productivity, high susceptibility to common bunt (Tilletia spp.) and to leaf rust (Puccinia recondita Rob. ex Desm.), but only in the rainy season. A mutation breeding programme using gamma irradiation has been started in 1978 to improve this cultivar. Seeds of all main tillers from M 1 plants were harvested and artificially inoculated with teliospores of Tilletia spp. All the seeds from healthy M 2 plants were inoculated again and sown in the same area. Out of 22920 M 3 plants, 244 resistant ones were selected. During subsequent screening for 4 generations, however, only 3 mutants were confirmed

  14. Study on creation and utilization of induced mutation rice materials

    International Nuclear Information System (INIS)

    Pang Aijun; Peng Weizheng; Pang Boliang; Peng Xuanming; Yang Zhen; Zhang Xianxin; Zhang Yuanhai

    2011-01-01

    60 Co γ-ray, spaceflight, laser were respectively or combinedly used to treat rice lines or hybrid materials. Many special type of seed breed lines, including high yielding ones, top quality ones, stunt stem ones, disease/pest resistent ones, colourful rices, big size of grain ones etc. were selected from the mutation materials, some were directly used as new varieties and some were indirectly used to breed hybrid varieties. All the new varieties such as 'xiangzaonuo No.1', 'xiangzaoxian No.20', 'xiangzaoxian No.21', 'xiangfu 994', 'peiliangyou 721', 'zhuliangyou 124' were popularly planted and great social and economical benefit was obtained. (authors)

  15. Induced mutations for fasciation in lentil (Lens culinaris Med.)

    International Nuclear Information System (INIS)

    Tyagi, B.S.; Gupta, P.K.

    1992-01-01

    A mutant with fascination in the upper part of stem was isolated in lentil (Lens culinaris) following combined treatment of gamma rays and EMS (200 Gy + 0.1% EMS). During the later stages of plant growth, due to slight flattening of stem and branches at the shoot apex, the plant appeared like a cluster of closely fused branches. Unlike earlier reported fascinated mutants in lentil, which were sterile [1], these fascinated mutants were fully fertile having normal reproductive organs, and thus are being maintained in homozygous state. Pods per bunch ranged from 2–10 as against 1–3 in the control. The mutants also differed from control in chlorophyll a and b content and other quantitative characters. The segregation data suggested monogenic recessive nature of the mutation

  16. Neutron-induced mutation experiments. Comprehensive report, March 1, 1977-August 31, 1980

    International Nuclear Information System (INIS)

    Abrahamson, S.

    1981-02-01

    Neutron-induced X-linked lethal mutations were induced in Drosophila melanogaster oogonia at energies of .43, .66, 2, and 6 MeV. The 37 irradiations were carried out at the RARAF facility at Brookhaven National Laboratory. RBE's (relative to x-ray data similarly collected) were calculated to be .43 MeV to 4.8; .66 MeV to 4.0; 2 MeV to 3.2; and 6 MeV to 2.9. The dose/frequency response curves for all energies best fit a linear rather than a linear-quadratic model following regression analyses. Control data for specific locus mutations (420,000 tests) were gathered. This data, combined with other data (both X-linked lethal and specific locus) has been used to estimate the number of loci on the X-chromosome of Drosophila which can mutate to recessive lethals

  17. Kinetics of gene and chromosome mutations induced by UV-C in yeast Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Koltovaya, N.; Kokoreva, A.; Senchenko, D.; Shvaneva, N.; Zhuchkina, N.

    2017-01-01

    The systematic study of the kinetics of UV-induced gene and structural mutations in eukaryotic cells was carried out on the basis of model yeast S. cerevisiae. A variety of genetic assays (all types of base pair substitutions, frameshifts, forward mutations canl, chromosomal and plasmid rearrangements) in haploid strains were used. Yeast cells were treated by UV-C light of fluence of energy up to 200 J/m"2. The kinetics of the induced gene and structural mutations is represented by a linear-quadratic and exponential functions. The slope of curves in log-log plots was not constant, had the value 2-4 and depended on the interval of doses. It was suggested that it is the superposition and dynamics of different pathways form the mutagenic responses of eukaryotic cells to UV-C light that cause the high-order curves. [ru

  18. Research highlights on: the use of induced mutations for plant improvement in Malaysia

    International Nuclear Information System (INIS)

    1998-01-01

    Nuclear techniques play an increasingly valuable role in agricultural research and development. The collaborative work of IAEA and FAO has been instrumental to the progress. The nuclear techniques are now used in a wide range of applications including crop improvement. In the initial years, many plant breeders had difficulty in believing that induced mutations through radiation had any relevance to their conventional procedures. But attitudes have greatly changed, in great part due to the Joint Division's programmes. The result was a high number of improved new varieties bred to date with the help of induced mutations, including some in this country. This publication is intended primarily to gather and put in order all information on the research and work on the use of induced mutations for plant breeding in the country. Its main purpose is to see if ensuing research efforts could be better coordinated, focused and enhanced in order to supplement the plant improvement programmes in the country. The task of collating the relevant information was not without difficulty since many of the work had been carried out long time ago; their objectives generally were quite broad; and the results essentially not published, with some exceptions. Section I begins with thefntroduction, giving a brief account of the developments of induced mutations in Malaysia, the facilities available in various institutions and the role played by the National Committee on the Use of Mutations in Plant Breeding. The collaborative efforts of IAEA and IFNCC are also briefly described here, together with all the activates which they had supported in the past. Section 11 briefly describes the induced mutations and how they are produced and utilised in the plant improvement programmes, taking into consideration the safety precautions required, and the requirements of different crop species. Section III describes in greater details all the research that had been carried out in the country. The

  19. International symposium on induced mutations in plants (ISIM). Book of abstracts

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    The year 2008 will mark the 80th anniversary of mutation induction in crop plants. The application of mutation techniques, i.e. gamma rays and other physical and chemical mutagens, has generated a vast amount of genetic variability and has played a significant role in plant breeding and genetic studies. The widespread use of induced mutants in plant breeding programmes throughout the world has led to the official release of more than 2600 mutant crop varieties. A large number of these varieties (including cereals, pulses, oil, root and tuber crops, and ornamentals) have been released in developing countries, resulting in enormous positive economic impacts. The International Symposium on Induced Mutations in Plants (ISIM) will be the eighth in the Joint FAO/IAEA Programme's Symposium series dedicated exclusively to harnessing and disseminating information on current trends in induced mutagenesis in plants, the first of which was held in 1969 and the last in 1995. These previous symposia dealt with themes relating to the development of efficient protocols for induced mutagenesis and their role in the enhancement of quality traits, as well as resistance to biotic and abiotic stresses in crops and the integration of in vitro and molecular genetic techniques in mutation induction. Since 1995, there has been an increased interest within the scientific community, not only in the use of induced mutations for developing improved crop varieties and for the discovery of genes controlling important traits and in the understanding the functions and mechanisms of actions of these genes, but also in deciphering the biological nature of DNA damage, repair and mutagenesis. A symposium that brings together the key players in basic research, as well as in the development and application of technologies relating to the efficient use of induced mutations for crop improvement and empirical genetic studies, is therefore justified and necessary. Topics addressed at the symposium

  20. Detection of DNA oligonucleotides with base mutations by terahertz spectroscopy and microstructures.

    Directory of Open Access Journals (Sweden)

    Mingjie Tang

    Full Text Available DNA oligonucleotides with a 5-base mutation at the 3'-terminus were investigated by terahertz (THz spectroscopy in a marker-free manner. The four single-stranded oligonucleotides with 17nt have been detected with specificity on a microfluidic chip, and corroborated by spectral measurements with split-ring resonators. The number of hydrogen bonds formed between the oligonucleotide and its surrounding water molecules, deemed a key contribution to the THz absorption of biological solutions, was explored by molecular dynamics simulations to explain the experimental findings. Our work underlies the feasibility of THz spectroscopy combined with microstructures for marker-free detection of DNA, which may form the basis of a prospective diagnostic tool for studying genic mutation.

  1. Mutated N-ras does not induce p19 arf in CO25 cell line | Saleh ...

    African Journals Online (AJOL)

    The mouse cell line (CO25) used in this study was transfected with a glucocorticoid inducible mutated human N-ras oncogene under transcriptional control of the steroid-sensitive promoter of the mouse mammary tumors virus long terminal repeat MMTV-LTR. This study was aimed to investigate the expression of p19arf and ...

  2. Advances in improvement of stress tolerance by induced mutation and genetic transformation in alfalfa

    International Nuclear Information System (INIS)

    Huang Xin; Ye Hongxia; Shu Xiaoli; Wu Dianxing

    2008-01-01

    In order to provide references for stress-tolerant breeding of alfalfa, genetic basis of stress-tolerant traits was briefly introduced and advanced in improvement of stress-tolerance by induced mutation and genetic transformation in alfalfa were reviewed. (authors)

  3. Comprehensive detection of diverse exon 19 deletion mutations of EGFR in lung Cancer by a single probe set.

    Science.gov (United States)

    Bae, Jin Ho; Jo, Seong-Min; Kim, Hak-Sung

    2015-12-15

    Detection of exon 19 deletion mutation of EGFR, one of the most frequently occurring mutations in lung cancer, provides the crucial information for diagnosis and treatment guideline in non-small-cell lung cancer (NSCLC). Here, we demonstrate a simple and efficient method to detect various exon 19 deletion mutations of EGFR using a single probe set comprising of an oligo-quencher (oligo-Q) and a molecular beacon (MB). While the MB hybridizes to both the wild and mutant target DNA, the oligo-Q only binds to the wild target DNA, leading to a fluorescent signal in case of deletion mutation. This enables the comprehensive detection of the diverse exon 19 deletion mutations using a single probe set. We demonstrated the utility and efficiency of the approach by detecting the frequent exon 19 deletion mutations of EGFR through a real-time PCR and in situ fluorescence imaging. Our approach enabled the detection of genomic DNA as low as 0.02 ng, showing a detection limit of 2% in a heterogeneous DNA mixture, and could be used for detecting mutations in a single cell level. The present MB and oligo-Q dual probe system can be used for diagnosis and treatment guideline in NSCLC. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. An effective method for detection and analysis of DNA damage induced by heavy-ion beams

    International Nuclear Information System (INIS)

    Kazama, Y.; Saito, H.; Fujiwara, M.; Matsuyama, T.; Hayashi, Y.; Ryuto, H.; Fukunishi, N.; Abe, T.

    2007-01-01

    We have developed an efficient system to detect and analyze DNA mutations induced by heavy-ion beams in Arabidopsis thaliana. In this system, a stable transgenic Arabidopsis line that constitutively expresses a yellow fluorescent protein (YFP) by a single-copy gene at a genomic locus was constructed and irradiated with heavy-ion beams. The YFP gene is a target of mutagenesis, and its loss of function or expression can easily be detected by the disappearance of YFP signals in planta under microscopy. With this system, a sup(12)Csup(6+)- induced mutant with single deletion and multiple base changes was isolated

  5. Utilization of induced mutations for groundnut breeding in Uganda

    International Nuclear Information System (INIS)

    Busolo-Bulafu, C.M.

    1987-01-01

    Groundnuts (Arachis hypogaea L.) are on high demand in Uganda. There is, therefore, an urgent need to improve groundnut yields through breeding. The main objectives besides yield are the following: 1. To improve disease resistance: (a) rosette virus transmitted by aphids (Aphis craccivora); (b) leafspot caused by Cercospora arachidicola (early) and Cercosporidium personatum (late). 2. To advance the maturity period of high yielding varieties so as to fit better into the rainfall pattern of the main growing areas. 3. To improve seed uniformity, seed size and quality (protein, oil). 4. To reduce plant height by shortening the internodes so as to have more flower production near the ground. For mutation breeding three erect groundnut cultivars were used, Roxo a recommended commercial variety; Red Beauty (Bl) a recommended local variety and No. 534 a tan skinned variety. Seeds of the three varieties were irradiated in 1976 at the FAO/IAEA Agricultural Section of the IAEA Laboratory Seibersdorf, with 1500 rad of fast neutrons (Nf) or 20 krad of 60 Co gamma rays. The pedigree method of selection was used until M9. During 1985 and 1986, seven mutant selections of Red Beauty and one from Roxo were tested in replicated yield trials. Results are given. On the basis of plot yields some of the Red Beauty mutant lines outyielded the parent but not the commercial variety Roxo

  6. Induced mutations in beans and peas for resistance to rust

    International Nuclear Information System (INIS)

    Fadl, F.A.M.

    1983-01-01

    Gamma rays and ethyl methanesulphonate (EMS) were applied in a mutation-induction programme for rust resistance in bean and pea. Bean and pea seeds were pre-soaked 2 hours before irradiation with 9, 10 and 12 krad. For chemical mutagen treatments bean and pea seeds were pre-soaked for 8 hours and treated with 0.5 and 1.5% EMS for four hours. M 2 seeds of beans and peas were planted in 1979. Resistant M 2 plants were selected for their rust resistance and other morphological characters. M 3 seeds of selected plants were planted in 1980. In 1980 more seeds of the same varieties of beans and peas were treated with 0.1 and 0.3% EMS with the aim to produce rust-resistant mutants. Seed germination was reduced by gamma rays or EMS. Dwarf, malformed and abnormal plants were noticed. Some resistant M 2 plants selected gave high grain yields. Some were different in morphological characters. In the M 3 of selected plants various other mutant characters appeared, such as different height of plants, early and late flowering, resistance to powdery mildew in peas, altered grain yield, thickness of stem, pod shape and flower colour. (author)

  7. Diagnostic markers for the detection of ovarian cancer in BRCA1 mutation carriers.

    Directory of Open Access Journals (Sweden)

    Daphne Gschwantler-Kaulich

    Full Text Available Screening for ovarian cancer (OC in women at high risk consists of a combination of carbohydrate antigen 125 (CA125 and transvaginal ultrasound, despite their low sensitivity and specificity. This could be improved by the combination of several biomarkers, which has been shown in average risk patients but has not been investigated until now in female BRCA mutation carriers.Using a multiplex, bead-based, immunoassay system, we analyzed the concentrations of leptin, prolactin, osteopontin, insulin-like growth factor II, macrophage inhibitory factor, CA125 and human epididymis antigen 4 in 26 healthy wild type women, 26 healthy BRCA1 mutation carriers, 28 wildtype OC patients and 26 OC patients with BRCA1 mutation.Using the ROC analysis, we found a high overall sensitivity of 94.3% in differentiating healthy controls from OC patients with comparable results in the wildtype subgroup (sensitivity 92.8%, AUC = 0.988; p = 5.2e-14 as well as in BRCA1 mutation carriers (sensitivity 95.2%, AUC = 0.978; p = 1.7e-15 at an overall specificity of 92.3%. The used algorithm also allowed to identify healthy BRCA1 mutation carriers when compared to healthy wildtype women (sensitivity 88.4%, specificity 80.7%, AUC = 0.895; p = 6e-08, while this was less pronounced in patients with OC (sensitivity 66.7%, specificity 67.8%, AUC = 0.724; p = 0.00065.We have developed an algorithm, which can differentiate between healthy women and OC patients and have for the first time shown, that such an algorithm can also be used in BRCA mutation carriers. To clarify a suggested benefit to the existing early detection program, large prospective trials with mainly early stage OC cases are warranted.

  8. [Clinical relevance of ESR1 circulating mutations detection in hormone receptor positive metastatic breast cancer].

    Science.gov (United States)

    Clatot, Florian; Perdrix, Anne; Sefrioui, David; Sarafan-Vasseur, Nasrin; Di Fiore, Frédéric

    2018-01-01

    If hormone therapy is a key treatment for hormone receptor positive advanced breast cancers, secondary resistance occurs as a rule. Recently, acquired alterations of the ESR1 gene have been identified as a mechanism of resistance on aromatase inhibitor (AI) treatment. The selective pressure by AI exposure during the metastatic setting triggers the emergence of ESR1 activating mutations. In that context, the "liquid biopsy" concept has been used to detect this molecular resistance before progression. Thus, the ESR1 circulating mutation detection will soon be used in daily practice to help monitoring patients on AI treatment and provide an early change for specific therapies that still have to be determined in prospective clinical trials. This review will present the acquired ESR1 mutations, as well as the methods used for their detection in blood and the potential clinical impact of this approach for hormone receptor positive breast cancer management. Copyright © 2017 Société Française du Cancer. Published by Elsevier Masson SAS. All rights reserved.

  9. Application of a New Genetic Deafness Microarray for Detecting Mutations in the Deaf in China.

    Directory of Open Access Journals (Sweden)

    Hong Wu

    Full Text Available The aim of this study was to evaluate the GoldenGate microarray as a diagnostic tool and to elucidate the contribution of the genes on this array to the development of both nonsyndromic and syndromic sensorineural hearing loss in China.We developed a microarray to detect 240 mutations underlying syndromic and nonsyndromic sensorineural hearing loss. The microarray was then used for analysis of 382 patients with nonsyndromic sensorineural hearing loss (including 15 patients with enlarged vestibular aqueduct syndrome, 21 patients with Waardenburg syndrome, and 60 unrelated controls. Subsequently, we analyzed the sensitivity, specificity, and reproducibility of this new approach after Sanger sequencing-based verification, and also determined the contribution of the genes on this array to the development of distinct hearing disorders.The sensitivity and specificity of the microarray chip were 98.73% and 98.34%, respectively. Genetic defects were identified in 61.26% of the patients with nonsyndromic sensorineural hearing loss, and 9 causative genes were identified. The molecular etiology was confirmed in 19.05% and 46.67% of the patients with Waardenburg syndrome and enlarged vestibular aqueduct syndrome, respectively.Our new mutation-based microarray comprises an accurate and comprehensive genetic tool for the detection of sensorineural hearing loss. This microarray-based detection method could serve as a first-pass screening (before next-generation-sequencing screening for deafness-causing mutations in China.

  10. Detecting β-thalassaemia mutations from a single cell by PEP and RDB

    Institute of Scientific and Technical Information of China (English)

    YI Ping; LI Li; YAO Hong; ZHOU Yuan-guo; DENG Bing; CHEN Zhu-qin

    2006-01-01

    Objective:To evaluate the possibility of the technology involving PEP and RDB for detecting β-thalassaemia multipoint mutations from a single cell simultaneously. Methods: A set of allele specific oligonucleotide (ASO) probes used for detecting 8 familiar β-thalassaemia mutations (CD41-42, IVS- Ⅱ -654, CD17, TATA box nt-28, CD71-72, TATA box nt-29, CD26, IVS- Ⅰ -5) were immobilized on a strip of nylon membrane. The genome of a individual cell was amplified by primer extension preamplification (PEP) with the mixture of15-base random oligonucleotides. The aliquots from PEP were used to amplify the objective gene fractions of β-thalassaemia gene by nested or semi-nested PCR. The membrane was hybridized with the final amplified products and then treated with Streptavidin-HRP and color development.Results :Totally 30 lymphocytes were picked up from blood samples of 1 healthy female and 4 patients with known β-thalassaemia mutations respectively. Each single lymphocyte was lysed in the proteinase K buffer. The amplification efficacy was 94.0% and alle drop-out(ADO) rate was 8.0%. Revert dot blot (RDB) was applied to the final amplified products from the 5 participants. The results of diagnosis were the same to the expected, and their genotypes were N/N, CD17 (A→T)/N, IVS- Ⅱ -654(C→T)/CD17(A → T), CD41-42 (-CTTT)/N and TATA box nt-28 (A→G)/N, respectively. Conclusion: The technology involving PEP and RDB could detectmultiple β-thalassaemia mutations from a single cell simultaneously,and the research provides experimental evidences for the feasibility of applying PEP and DNA array technology to screening multiple genetic mutations from a single cell, and will be applied to preimplantation genetic diagnosis and non-invasive prenatal diagnosis for β-thalassaemia.

  11. Detection of Anti-Hepatitis B Virus Drug Resistance Mutations Based on Multicolor Melting Curve Analysis.

    Science.gov (United States)

    Mou, Yi; Athar, Muhammad Ammar; Wu, Yuzhen; Xu, Ye; Wu, Jianhua; Xu, Zhenxing; Hayder, Zulfiqar; Khan, Saeed; Idrees, Muhammad; Nasir, Muhammad Israr; Liao, Yiqun; Li, Qingge

    2016-11-01

    Detection of anti-hepatitis B virus (HBV) drug resistance mutations is critical for therapeutic decisions for chronic hepatitis B virus infection. We describe a real-time PCR-based assay using multicolor melting curve analysis (MMCA) that could accurately detect 24 HBV nucleotide mutations at 10 amino acid positions in the reverse transcriptase region of the HBV polymerase gene. The two-reaction assay had a limit of detection of 5 copies per reaction and could detect a minor mutant population (5% of the total population) with the reverse transcriptase M204V amino acid mutation in the presence of the major wild-type population when the overall concentration was 10 4 copies/μl. The assay could be finished within 3 h, and the cost of materials for each sample was less than $10. Clinical validation studies using three groups of samples from both nucleos(t)ide analog-treated and -untreated patients showed that the results for 99.3% (840/846) of the samples and 99.9% (8,454/8,460) of the amino acids were concordant with those of Sanger sequencing of the PCR amplicon from the HBV reverse transcriptase region (PCR Sanger sequencing). HBV DNA in six samples with mixed infections consisting of minor mutant subpopulations was undetected by the PCR Sanger sequencing method but was detected by MMCA, and the results were confirmed by coamplification at a lower denaturation temperature-PCR Sanger sequencing. Among the treated patients, 48.6% (103/212) harbored viruses that displayed lamivudine monoresistance, adefovir monoresistance, entecavir resistance, or lamivudine and adefovir resistance. Among the untreated patients, the Chinese group had more mutation-containing samples than did the Pakistani group (3.3% versus 0.56%). Because of its accuracy, rapidness, wide-range coverage, and cost-effectiveness, the real-time PCR assay could be a robust tool for the detection if anti-HBV drug resistance mutations in resource-limited countries. Copyright © 2016, American Society for

  12. Current status and outlook perspectives of induced mutations for plant improvement

    International Nuclear Information System (INIS)

    Liu Luxiang; Guo Huijun; Zhao Linshu; Li Junhui; Gu Jiayu; ZZhao Shirong; Wang Jing

    2009-01-01

    Since 1928, induced mutations have played a significant role in solving world food and nutritional security problems through mutant germplasm enhancement and new mutant variety development. According to incomplete statistics, up to September 2009, induced mutations have officially released 3088 mutant cultivars in more than 170 crop species by more than 60 countries in the world. China tanks the first in the world, which has have released 802 mutant cultivars in 45 crop species, and takes more than a quarter of the total number of mutant varieties in the FAO/IAEA database. The maximum annually accumulated planting area of the mutant varieties was 9 million hectares, with an additional increase of 1.5 billion kilograms to national output of grain, cotton, oil, being converted to social and economic benefits of more than 2 billion RMB. The recent development and application of accelerator ion beam irradiation, the spaceflight environment and the other new mutation means, as well as the effective use of traditional radiation mutagenesis are becoming more active in crop improvement and new gene discovery. The advent of plant genomics and high throughput DNA techniques, such as TILLING, have opened a new era of molecular mutation breeding, which will overcome the limitations of conventional mutation breeding and play a significant role in solving China and world food security. (authors)

  13. Membrane composition and physiological activity of plastids from an oenothera plastome mutator-induced chloroplast mutant.

    Science.gov (United States)

    Johnson, E M; Sears, B B

    1990-01-01

    Plastids were isolated from a plastome mutator-induced mutant (pm7) of Oenothera hookeri and were analyzed for various physiological and biochemical attributes. No photosynthetic electron transport activity was detected in the mutant plastids. This is consistent with previous ultrastructural analysis showing the absence of thylakoid membranes in the pm7 plastids and with the observation of aberrant processing and accumulation of chloroplast proteins in the mutant. In comparison to wild type, the mutant tissue lacks chlorophyll, and has significant differences in levels of four fatty acids. The analyses did not reveal any differences in carotenoid levels nor in the synthesis of several chloroplast lipids. The consequences of the altered composition of the chloroplast membrane are discussed in terms of their relation to the aberrant protein processing of the pm7 plastids. The pigment, fatty acid, and lipid measurements were also performed on two distinct nuclear genotypes (A/A and A/C) which differ in their compatibility with the plastid genome (type I) contained in these lines. In these cases, only chlorophyll concentrations differed significantly.

  14. Detection and Analysis of EGFR and KRAS Mutations 
in the Patients with Lung Squamous Cell Carcinomas

    Directory of Open Access Journals (Sweden)

    Hui ZHANG

    2015-10-01

    Full Text Available Background and objective Activating mutations in epidermal growth factor receptor (EGFR and KRAS are important markers in non-small cell lung cancer. However, EGFR and KRAS gene mutations in lung squamous cell carcinoma are rarely reported. The aim of this study was to analyze EGFR and KRAS gene mutation rate and their relationship with clinical features in patients with lung squamous cell carcinomas. Methods A total of 139 patients undergoing treatment for naïve lung squamous cell carcinomas with tumor tissue samples available for testing were recruited. EGFR and KRAS mutation statuses of the tumor samples were detected using a mutant enriched liquid chip. Results Of the 139 cases of lung squamous cell carcinoma, EGFR mutations were detected in 25 cases (18%, KRAS mutations were detected in 7 cases (5%, and the presence of both EGFR and KRAS mutations was detected in 1 case (0.7%. EGFR mutations occurred more often in females than in males (33.3% vs 16.5% and in patients that never smoked than in those who smoke (29.6% vs 16.1%. However, the difference did not reach statistical significance (P>0.05. No significant differences were observed in age, stage, and different biopsy type. KRAS mutations occurred more often in males than in females (5.5% vs 0%, but the difference did not reach statistical significance (P>0.05. No significant differences were observed in age, stage, different biopsy type, and smoking status (P>0.05. Conclusion EGFR and KRAS mutations were low in lung squamous cell carcinomas, and had no significant correlation with clinical features. Before using tyrosine kinase inhibitor targeted therapy, EGFR and KRAS mutations should be detected in patients with lung squamous cell carcinomas.

  15. Anti-HBV treatment induces novel reverse transcriptase mutations with reflective effect on HBV S antigen

    NARCIS (Netherlands)

    Cento, Valeria; van Hemert, Formijn; Neumann-Fraune, Maria; Mirabelli, Carmen; Di Maio, Velia-Chiara; Salpini, Romina; Bertoli, Ada; Micheli, Valeria; Gubertini, Guido; Romano, Sara; Visca, Michela; de Sanctis, Giuseppe-Maria; Berkhout, Ben; Marino, Nicoletta; Mazzotta, Francesco; Cappiello, Giuseppina; Spanò, Alberto; Sarrecchia, Cesare; Ceccherini-Silberstein, Francesca; Andreoni, Massimo; Angelico, Mario; Verheyen, Jens; Perno, Carlo Federico; Svicher, Valentina

    2013-01-01

    The identification of novel reverse-transcriptase (RT) drug-resistance mutations is critical in predicting the probability of success to anti-HBV treatment. Furthermore, due to HBV-RT/HBsAg gene-overlap, they can have an impact on HBsAg-detection and quantification. 356 full-length HBV-RT sequences

  16. The improvement of cisantana rice variety through induced mutation

    International Nuclear Information System (INIS)

    Mugiono; Lilik Harsanti; Azri Kusuma Dewi

    2009-01-01

    The continuous improvement for rice through breeding is necessary to obtain new varieties with good quality and quantity. Cisantana variety hairy tips could be improved by mutation breeding. Seeds of Cisantana variety was irradiated by gamma rays ( 60 Co) at doses of 0.10, 0.20 and 0.30 kGy respectively at the Center for Application of Isotope and Radiation (CAIR) - Batan, Pasar Jumat, Jakarta. There after the irradiated seeds were planted as M1 plants at the CAIR’S experiment field in the dry season of 2000. Selection was carried out at the M2 generation and stressed on early maturity and bald spike. This was done at the experiment field at Pusakanegara - Subang in the Wet season of 2001/2002. From this population 19 mutants having early maturity and bald spike lets were selected. Purification in the next generation obtained 10 mutants which were homogeneous and without segregation. From these 10 mutants two mutant lines Obs-1688/PsJ and Obs-1692/PsJ were further tested. These two mutant lines showed good productivity and adaptability when tested at several locations. The resistance test for brown plant hopper and bacterial leaf blight disease showed that these two mutant lines are resistant to biotype 1 and 2, and medium resistant to biotype 3 of brown plant hopper, and also resistant to strain 3 and medium resistant to strain IV of bacterial leaf blight disease. These two mutant lines have good rice quality and were gelatinous. The Obs-1688/PsJ and Obs-1692/PsJ mutant lines were released as new rice varieties by the Minister of Agriculture and officially address as Mira-1 at 2006 and Bestari at 2008, respectively. (author)

  17. SV2: accurate structural variation genotyping and de novo mutation detection from whole genomes.

    Science.gov (United States)

    Antaki, Danny; Brandler, William M; Sebat, Jonathan

    2018-05-15

    Structural variation (SV) detection from short-read whole genome sequencing is error prone, presenting significant challenges for population or family-based studies of disease. Here, we describe SV2, a machine-learning algorithm for genotyping deletions and duplications from paired-end sequencing data. SV2 can rapidly integrate variant calls from multiple structural variant discovery algorithms into a unified call set with high genotyping accuracy and capability to detect de novo mutations. SV2 is freely available on GitHub (https://github.com/dantaki/SV2). jsebat@ucsd.edu. Supplementary data are available at Bioinformatics online.

  18. PCR-RFLP to Detect Codon 248 Mutation in Exon 7 of "p53" Tumor Suppressor Gene

    Science.gov (United States)

    Ouyang, Liming; Ge, Chongtao; Wu, Haizhen; Li, Suxia; Zhang, Huizhan

    2009-01-01

    Individual genome DNA was extracted fast from oral swab and followed up with PCR specific for codon 248 of "p53" tumor suppressor gene. "Msp"I restriction mapping showed the G-C mutation in codon 248, which closely relates to cancer susceptibility. Students learn the concepts, detection techniques, and research significance of point mutations or…

  19. One-step isothermal detection of multiple KRAS mutations by forming SNP specific hairpins on a gold nanoshell.

    Science.gov (United States)

    Chung, Chan Ho; Kim, Joong Hyun

    2018-04-24

    We developed a one-step isothermal method for typing multiple KRAS mutations using a designed set of primers to form a hairpin on a gold nanoshell upon being ligated by a SNP specific DNA ligase after binding of targets. As a result, we could detect as low as 20 attomoles of KRAS mutations within 1 h.

  20. Direct detection of common and rare inversion mutations in the genetic diagnosis of severe hemophilia A

    Energy Technology Data Exchange (ETDEWEB)

    Windsor, A.S.; Lillicrap, D.P.; Taylor, S.A.M. [Queen`s Univ., Ontario (Canada)

    1994-09-01

    Approximately 50% of the cases of severe hemophilia A (factor VIII:C < 0.01 units/ml) may be due to gross rearrangements of the factor VIII gene. The mutation involves homologous sequences upstream of the factor VIII locus and within intron 22 in an intrachromosomal recombination, inversion, event. The rearrangements can readily be detected on a Southern blot using a probe that is complementary to sequences from within intron 22. We describe here the analysis of this mutation in 71 severe hemophilia A patients. Thirty two of the patients (45%) showed evidence of a rearrangement. Five different patterns of rearrangements were seen, two of which have previously been described and account for the majority of cases (pattern 1, 70% and pattern 2, 16%). Three other abnormal patterns were observed. The inversion mechanism does not usually result in the loss or gain of any genetic material, but in one patient, in whom a unique rearrangement pattern was observed (pattern 3), we have previously documented a gross deletion which removes exons 1-22 of the factor VII gene as well as sequences 5{prime} to the gene. In another individual a fourth pattern in which an extra 19.0 kb band is present was detected. In this case it is unclear as to whether the rearrangement is responsible for the disease or is simply coincident normal variation. A fifth pattern, in which an extra 16.0 kb band was detected, was observed in a family with a new mutation causing hemophilia A. The affected individual and his mother inherited a de novo rearrangement of the factor VIII gene from his unaffected grandfather, implicating it as the cause of the disease. In conclusion, testing for the factor VIII inversion mutation was positive in approximately 45% of severe hemophiliacs, 72% of whom were isolated cases, and as such should constitute the initial stage in the genetic testing protocol for these patients` families.

  1. Frequencies of aneuploidy and dominant lethal mutations in young female mice induced by low dose γ-rays

    International Nuclear Information System (INIS)

    Yao Suyan; Zhang Chaoyang; Dai Lianlian; Gao Changwen

    1991-01-01

    Relationship between aneuploidy, dominant lethal mutations and doses in young feral mice induced by low dose γ-rays was examined. The results suggest that the frequencies of aneuploidy of embryos increased at 0.15 Gy, but increases at over 0.50 Gy after irradiation in groups. The frequencies of aneuploidy and dominant lethal mutations increased with increasing doses and fitted linear relationship. This dose-response relationship of trisomic was not significant. The frequency of dominant lethal mutations induced by 60 Co γ irradiation is 5.59%. The effect of dominant lethal mutation is higher than that of the aneuploidy

  2. Inflammation, gene mutation and photoimmunosuppression in response to UVR-induced oxidative damage contributes to photocarcinogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Halliday, Gary M. [Dermatology Research Laboratories, Division of Medicine, Melanoma and Skin Cancer Research Institute, Royal Prince Alfred Hospital at the University of Sydney, Sydney, NSW (Australia)]. E-mail: garyh@med.usyd.edu.au

    2005-04-01

    Ultraviolet (UV) radiation causes inflammation, gene mutation and immunosuppression in the skin. These biological changes are responsible for photocarcinogenesis. UV radiation in sunlight is divided into two wavebands, UVB and UVA, both of which contribute to these biological changes, and therefore probably to skin cancer in humans and animal models. Oxidative damage caused by UV contributes to inflammation, gene mutation and immunosuppression. This article reviews evidence for the hypothesis that UV oxidative damage to these processes contributes to photocarcinogenesis. UVA makes a larger impact on oxidative stress in the skin than UVB by inducing reactive oxygen and nitrogen species which damage DNA, protein and lipids and which also lead to NAD+ depletion, and therefore energy loss from the cell. Lipid peroxidation induces prostaglandin production that in association with UV-induced nitric oxide production causes inflammation. Inflammation drives benign human solar keratosis (SK) to undergo malignant conversion into squamous cell carcinoma (SCC) probably because the inflammatory cells produce reactive oxygen species, thus increasing oxidative damage to DNA and the immune system. Reactive oxygen or nitrogen appears to cause the increase in mutational burden as SK progress into SCC in humans. UVA is particularly important in causing immunosuppression in both humans and mice, and UV lipid peroxidation induced prostaglandin production and UV activation of nitric oxide synthase is important mediators of this event. Other immunosuppressive events are likely to be initiated by UV oxidative stress. Antioxidants have also been shown to reduce photocarcinogenesis. While most of this evidence comes from studies in mice, there is supporting evidence in humans that UV-induced oxidative damage contributes to inflammation, gene mutation and immunosuppression. Available evidence implicates oxidative damage as an important contributor to sunlight-induced carcinogenesis in humans.

  3. Inflammation, gene mutation and photoimmunosuppression in response to UVR-induced oxidative damage contributes to photocarcinogenesis

    International Nuclear Information System (INIS)

    Halliday, Gary M.

    2005-01-01

    Ultraviolet (UV) radiation causes inflammation, gene mutation and immunosuppression in the skin. These biological changes are responsible for photocarcinogenesis. UV radiation in sunlight is divided into two wavebands, UVB and UVA, both of which contribute to these biological changes, and therefore probably to skin cancer in humans and animal models. Oxidative damage caused by UV contributes to inflammation, gene mutation and immunosuppression. This article reviews evidence for the hypothesis that UV oxidative damage to these processes contributes to photocarcinogenesis. UVA makes a larger impact on oxidative stress in the skin than UVB by inducing reactive oxygen and nitrogen species which damage DNA, protein and lipids and which also lead to NAD+ depletion, and therefore energy loss from the cell. Lipid peroxidation induces prostaglandin production that in association with UV-induced nitric oxide production causes inflammation. Inflammation drives benign human solar keratosis (SK) to undergo malignant conversion into squamous cell carcinoma (SCC) probably because the inflammatory cells produce reactive oxygen species, thus increasing oxidative damage to DNA and the immune system. Reactive oxygen or nitrogen appears to cause the increase in mutational burden as SK progress into SCC in humans. UVA is particularly important in causing immunosuppression in both humans and mice, and UV lipid peroxidation induced prostaglandin production and UV activation of nitric oxide synthase is important mediators of this event. Other immunosuppressive events are likely to be initiated by UV oxidative stress. Antioxidants have also been shown to reduce photocarcinogenesis. While most of this evidence comes from studies in mice, there is supporting evidence in humans that UV-induced oxidative damage contributes to inflammation, gene mutation and immunosuppression. Available evidence implicates oxidative damage as an important contributor to sunlight-induced carcinogenesis in humans

  4. Highly sensitive chemiluminescent point mutation detection by circular strand-displacement amplification reaction.

    Science.gov (United States)

    Shi, Chao; Ge, Yujie; Gu, Hongxi; Ma, Cuiping

    2011-08-15

    Single nucleotide polymorphism (SNP) genotyping is attracting extensive attentions owing to its direct connections with human diseases including cancers. Here, we have developed a highly sensitive chemiluminescence biosensor based on circular strand-displacement amplification and the separation by magnetic beads reducing the background signal for point mutation detection at room temperature. This method took advantage of both the T4 DNA ligase recognizing single-base mismatch with high selectivity and the strand-displacement reaction of polymerase to perform signal amplification. The detection limit of this method was 1.3 × 10(-16)M, which showed better sensitivity than that of most of those reported detection methods of SNP. Additionally, the magnetic beads as carrier of immobility was not only to reduce the background signal, but also may have potential apply in high through-put screening of SNP detection in human genome. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Enzyme-Free Detection of Mutations in Cancer DNA Using Synthetic Oligonucleotide Probes and Fluorescence Microscopy

    DEFF Research Database (Denmark)

    Miotke, Laura; Maity, Arindam; Ji, Hanlee

    2015-01-01

    BACKGROUND: Rapid reliable diagnostics of DNA mutations are highly desirable in research and clinical assays. Current development in this field goes simultaneously in two directions: 1) high-throughput methods, and 2) portable assays. Non-enzymatic approaches are attractive for both types...... 1000-fold above the potential detection limit. CONCLUSION: Overall, the novel assay we describe could become a new approach to rapid, reliable and enzyme-free diagnostics of cancer or other associated DNA targets. Importantly, stoichiometry of wild type and mutant targets is conserved in our assay...... of methods since they would allow rapid and relatively inexpensive detection of nucleic acids. Modern fluorescence microscopy is having a huge impact on detection of biomolecules at previously unachievable resolution. However, no straightforward methods to detect DNA in a non-enzymatic way using fluorescence...

  6. Herpesvirus telomerase RNA (vTR with a mutated template sequence abrogates herpesvirus-induced lymphomagenesis.

    Directory of Open Access Journals (Sweden)

    Benedikt B Kaufer

    2011-10-01

    Full Text Available Telomerase reverse transcriptase (TERT and telomerase RNA (TR represent the enzymatically active components of telomerase. In the complex, TR provides the template for the addition of telomeric repeats to telomeres, a protective structure at the end of linear chromosomes. Human TR with a mutation in the template region has been previously shown to inhibit proliferation of cancer cells in vitro. In this report, we examined the effects of a mutation in the template of a virus encoded TR (vTR on herpesvirus-induced tumorigenesis in vivo. For this purpose, we used the oncogenic avian herpesvirus Marek's disease virus (MDV as a natural virus-host model for lymphomagenesis. We generated recombinant MDV in which the vTR template sequence was mutated from AATCCCAATC to ATATATATAT (vAU5 by two-step Red-mediated mutagenesis. Recombinant viruses harboring the template mutation replicated with kinetics comparable to parental and revertant viruses in vitro. However, mutation of the vTR template sequence completely abrogated virus-induced tumor formation in vivo, although the virus was able to undergo low-level lytic replication. To confirm that the absence of tumors was dependent on the presence of mutant vTR in the telomerase complex, a second mutation was introduced in vAU5 that targeted the P6.1 stem loop, a conserved region essential for vTR-TERT interaction. Absence of vTR-AU5 from the telomerase complex restored virus-induced lymphoma formation. To test if the attenuated vAU5 could be used as an effective vaccine against MDV, we performed vaccination-challenge studies and determined that vaccination with vAU5 completely protected chickens from lethal challenge with highly virulent MDV. Taken together, our results demonstrate 1 that mutation of the vTR template sequence can completely abrogate virus-induced tumorigenesis, likely by the inhibition of cancer cell proliferation, and 2 that this strategy could be used to generate novel vaccine candidates

  7. Detection of MPL exon10 mutations in 103 Chinese patients with JAK2V617F-negative myeloproliferative neoplasms.

    Science.gov (United States)

    Chen, Xiuhua; Qi, Xiling; Tan, Yanhong; Xu, Zhifang; Xu, Aining; Zhang, Linlin; Wang, Hongwei

    2011-06-15

    JAK2V617F mutation has been reported in 90% of patients with polycythemia vera (PV) and about 50% of patients with essential thromobocythemia (ET) and primary myelofibrosis (PMF). Recently, acquired mutations in the transmembrane-juxtamembrane region of MPL (MPLW515 mutations) have been reported in approximately 5% of JAK2V617F-negative PMF and about 1% of all cases of ET. MPL is the receptor for thrombopoietin that regulates the production of platelets by bone marrow. It is likely that some mutations more closely related to ET in MPL exon10 may have been missed by current assays. We inferred that there might be other mutations in MPL exon10 for MPN patients in addition to MPLW515 mutations. To investigate its mutation types and prevalence in Chinese patients with myeloproliferative neoplasms (MPN), we performed mutation detection on MPL exon10 in 103 JAK2V617F-negative MPN patients by single strand conformation polymorphism (SSCP) and allele-specific PCR (AS-PCR) combined with sequencing. As a result, one previously unrecognized MPL mutation (12-bp in-frame insertion) was identified in one patient with ET in addition to an MPLW515K mutation identified in one PMF patient. This confirms our hypothesis that BCR/ABL negative and JAK2V617F-negative MPN patients have other mutations besides W515 mutation in MPL exon10 and mutations other than single nucleotide exchange also exist. In addition, MPL mutation was associated with Chinese MPN patients. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. Optimization of heteroduplex analysis for the detection of BRCA mutations and SNPs

    Directory of Open Access Journals (Sweden)

    Lucian Negura

    2011-02-01

    Full Text Available BRCA1 and BRCA2 are tumour suppressor genes whose mutant phenotypes predispose to breast and ovarian cancer. Screening for mutations in these genes is now standard practice for hereditary breast and ovarian cancer (HBOC cases in Europe, and permits medical follow-up and genetic counselling adapted to the needs of individuals in such families. Currently, most laboratories performing diagnostic analysis of the BRCA genes use PCR of exons and intron-exon boundaries coupled to a pre-screening step to identify anomalous amplicons. The techniques employed for the detection of mutations and SNPs have evolved over time and vary in sensitivity, specificity and cost-effectiveness. As a variant for pre-screening techniques, we chose the recently developed Surveyor® heteroduplex cleavage method as a sensitive and specific technique to reveal anomalous amplicons of the BRCA genes, using only basic laboratory equipment and agarose gel electrophoresis. Here we present the detection of either mutations or SNPs within the BRCA1 exon 7, using heteroduplex analysis (HA by mismatch-specific endonuclease, confirmed by dideoxy sequencing.

  9. Pyrosequencing, a method approved to detect the two major EGFR mutations for anti EGFR therapy in NSCLC

    Directory of Open Access Journals (Sweden)

    Richard Marie-Jeanne

    2011-05-01

    Full Text Available Abstract Background Epidermal Growth Factor Receptor (EGFR mutations, especially in-frame deletions in exon 19 (ΔLRE and a point mutation in exon 21 (L858R predict gefitinib sensitivity in patients with non-small cell lung cancer. Several methods are currently described for their detection but the gold standard for tissue samples remains direct DNA sequencing, which requires samples containing at least 50% of tumor cells. Methods We designed a pyrosequencing assay based on nested PCR for the characterization of theses mutations on formalin-fixed and paraffin-embedded tumor tissue. Results This method is highly specific and permits precise characterization of all the exon 19 deletions. Its sensitivity is higher than that of "BigDye terminator" sequencing and enabled detection of 3 additional mutations in the 58 NSCLC tested. The concordance between the two methods was very good (97.4%. In the prospective analysis of 213 samples, 7 (3.3% samples were not analyzed and EGFR mutations were detected in 18 (8.7% patients. However, we observed a deficit of mutation detection when the samples were very poor in tumor cells. Conclusions pyrosequencing is then a highly accurate method for detecting ΔLRE and L858R EGFR mutations in patients with NSCLC when the samples contain at least 20% of tumor cells.

  10. Induced micro-mutations in Solanum khasianum Clarke

    International Nuclear Information System (INIS)

    Bhattacharyya, B.; Borua, P.K.; Talukdar, P.

    1996-01-01

    Extent of genetic variability for plant height, branches/plant, leaves/plant, spines/leaf, fruits/plant, seeds/fruit, fresh weight of fruits/plant and dry weight of fruits/plant was studied in spined and spineless strains of Solanum khasianum Clarke, following exposure of seeds to seven doses of gamma rays. Gamma ray treatments induced sufficient genetic variability in M 2 generation for the characters particularly in spined strain. Genotypic and phenotypic coefficient of variation and heritability in broad sense were high for spines/leaf, fruits/plant, fresh and dry weight of fruits/plant. High heritability was accompanied by high genetic advance for fresh and dry weight of fruits/plant, seeds/fruit and fruits/plant. Spineless strain was found to be more sensitive to increased gamma ray exposure in comparison to spined strain. (author). 7 refs., 4 tabs

  11. Evolution of improved varieties of sesame through induced mutations

    International Nuclear Information System (INIS)

    Rahman, A.; Das, M.L.

    2001-01-01

    have 6-10% more oil in the seed as compared to black seeded ones. Combined analysis of variances for seed yield over locations revealed significant differences in the performance of the mutants over their source material. Mutants SM5 and SM7 proved superior in respect to seed and oil yield and other agronomic characters. The mutants were given on farm trials at various locations with two management practices, viz., research management with higher inputs and farmers' management practices with low or no inputs. In both management practices the mutants produced significantly higher yield compared to the source. Significant differences were found in seed yield in mutants/check (G), locations (L), management practices (M) and interaction between (GxL) while the interaction between management and location (MxL) was insignificant. Mutants SM5 and SM7 would be submitted to National Seed Board for registration as commercial high yielding mutant varieties. Some of the promising mutants will be utilized in cross-breeding programmes. The present report discusses the effect of mutagen on sesame genotypes, results obtained in different mutant generation and overall mutation breeding studies carried out throughout the project period starting from 1993 to 1997. (author)

  12. NF2 tumor suppressor gene: a comprehensive and efficient detection of somatic mutations by denaturing HPLC and microarray-CGH.

    Science.gov (United States)

    Szijan, Irene; Rochefort, Daniel; Bruder, Carl; Surace, Ezequiel; Machiavelli, Gloria; Dalamon, Viviana; Cotignola, Javier; Ferreiro, Veronica; Campero, Alvaro; Basso, Armando; Dumanski, Jan P; Rouleau, Guy A

    2003-01-01

    The NF2 tumor suppressor gene, located in chromosome 22q12, is involved in the development of multiple tumors of the nervous system, either associated with neurofibromatosis 2 or sporadic ones, mainly schwannomas and meningiomas. In order to evaluate the role of the NF2 gene in sporadic central nervous system (CNS) tumors, we analyzed NF2 mutations in 26 specimens: 14 meningiomas, 4 schwannomas, 4 metastases, and 4 other histopathological types of neoplasms. Denaturing high performance liquid chromatography (denaturing HPLC) and comparative genomic hybridization on a DNA microarray (microarray- CGH) were used as scanning methods for small mutations and gross rearrangements respectively. Small mutations were identified in six out of seventeen meningiomas and schwannomas, one mutation was novel. Large deletions were detected in six meningiomas. All mutations were predicted to result in truncated protein or in the absence of a large protein domain. No NF2 mutations were found in other histopathological types of CNS tumors. These results provide additional evidence that mutations in the NF2 gene play an important role in the development of sporadic meningiomas and schwannomas. Denaturing HPLC analysis of small mutations and microarray-CGH of large deletions are complementary, fast, and efficient methods for the detection of mutations in tumor tissues.

  13. P53 Gene Mutation as Biomarker of Radiation Induced Cell Injury and Genomic Instability

    International Nuclear Information System (INIS)

    Mukh-Syaifudin

    2006-01-01

    Gene expression profiling and its mutation has become one of the most widely used approaches to identify genes and their functions in the context of identify and categorize genes to be used as radiation effect markers including cell and tissue sensitivities. Ionizing radiation produces genetic damage and changes in gene expression that may lead to cancer due to specific protein that controlling cell proliferation altered the function, its expression or both. P53 protein encoded by p53 gene plays an important role in protecting cell by inducing growth arrest and or cell suicide (apoptosis) after deoxyribonucleic acid (DNA) damage induced by mutagen such as ionizing radiation. The mutant and thereby dysfunctional of this gene was found in more than 50% of various human cancers, but it is as yet unclear how p53 mutations lead to neoplastic development. Wild-type p53 has been postulated to play a role in DNA repair, suggesting that expression of mutant forms of p53 might alter cellular resistance to the DNA damage caused by radiation. Moreover, p53 is thought to function as a cell cycle checkpoint after irradiation, also suggesting that mutant p53 might change the cellular proliferative response to radiation. P53 mutations affect the cellular response to DNA damage, either by increasing DNA repair processes or, possibly, by increasing cellular tolerance to DNA damage. The association of p53 mutations with increased radioresistance suggests that alterations in the p53 gene might lead to oncogenic transformation. Current attractive model of carcinogenesis also showed that p53 gene is the major target of radiation. The majority of p53 mutations found so far is single base pair changes ( point mutations), which result in amino acid substitutions or truncated forms of the p53 protein, and are widely distributed throughout the evolutionary conserved regions of the gene. Examination of p53 mutations in human cancer also shows an association between particular carcinogens and

  14. Detection of epidermal growth factor receptor mutation in lung cancer by droplet digital polymerase chain reaction

    Directory of Open Access Journals (Sweden)

    Xu Q

    2015-06-01

    Full Text Available Qing Xu,1,* Yazhen Zhu,2,* Yali Bai,1 Xiumin Wei,1 Xirun Zheng,2 Mao Mao,1 Guangjuan Zheng21Translational Bioscience and Diagnostics, WuXi AppTec, Shanghai, 2Department of Pathology, Guangdong Provincial Hospital of TCM, Guangzhou University of Chinese Medicine, Guangdong Provincial Academy of Chinese Medical Sciences, Guangzhou, People’s Republic of China*These authors contributed equally to this workBackground: Two types of epidermal growth factor receptor (EGFR mutations in exon 19 and exon 21 (ex19del and L858R are prevalent in lung cancer patients and sensitive to targeted EGFR inhibition. A resistance mutation in exon 20 (T790M has been found to accompany drug treatment when patients relapse. These three mutations are valuable companion diagnostic biomarkers for guiding personalized treatment. Quantitative polymerase chain reaction (qPCR-based methods have been widely used in the clinic by physicians to guide treatment decisions. The aim of this study was to evaluate the technical and clinical sensitivity and specificity of the droplet digital polymerase chain reaction (ddPCR method in detecting the three EGFR mutations in patients with lung cancer.Methods: Genomic DNA from H1975 and PC-9 cells, as well as 92 normal human blood specimens, was used to determine the technical sensitivity and specificity of the ddPCR assays. Genomic DNA of formalin-fixed, paraffin-embedded specimens from 78 Chinese patients with lung adenocarcinoma were assayed using both qPCR and ddPCR.Results: The three ddPCR assays had a limit of detection of 0.02% and a wide dynamic range from 1 to 20,000 copies measurement. The L858R and ex19del assays had a 0% background level in the technical and clinical settings. The T790M assay appeared to have a 0.03% technical background. The ddPCR assays were robust for correct determination of EGFR mutation status in patients, and the dynamic range appeared to be better than qPCR methods. The ddPCR assay for T790M could detect

  15. The KRAS Strip Assay for detection of KRAS mutation in Egyptian patients with colorectal cancer (CRC): A pilot study

    International Nuclear Information System (INIS)

    Abd El Kader, Y.; Safwat, E.; Kassem, H.A.; Kassem, N.M.; Emera, G.

    2013-01-01

    Background: Epidermal growth factor receptor (EGFR) and its downstream factors KRAS and BRAF are mutated in several types of cancer, affecting the clinical response to EGFR inhibitors. Mutations in the EGFR kinase domain predict sensitivity to the tyrosine kinase inhibitors gefltinib and erlotinib in lung adenocarcinoma, while activating point mutations in KRAS and BRAF confer resistance to the anti-EGFR monoclonal antibody cetuximab in colorectal cancer. The development of new generation methods for systematic mutation screening of these genes will allow more appropriate therapeutic choices. Purpose: Detection of KRAS mutation in Egyptian colorectal cancer (CRC) patients by the KRAS Strip Assay. Methods: Examination of 20 colorectal cancer (CRC) patients is done to detect KRAS mutations by KRAS Strip Assay. For the Strip Assay, a mutant-enriched PCR was followed by hybridization to KRAS-specific probes bound to a nitrocellulose strip. Results: Among 20 patients, KRAS mutations were identified in 80% of patients by the KRAS Strip Assay. Conclusions: Our preliminary results suggest that KRAS Strip Assay is an alternative to protocols currently in use for KRAS mutation detection

  16. [Rapid detection of hot spot mutations of FGFR3 gene with PCR-high resolution melting assay].

    Science.gov (United States)

    Li, Shan; Wang, Han; Su, Hua; Gao, Jinsong; Zhao, Xiuli

    2017-08-10

    To identify the causative mutations in five individuals affected with dyschondroplasia and develop an efficient procedure for detecting hot spot mutations of the FGFR3 gene. Genomic DNA was extracted from peripheral blood samples with a standard phenol/chloroform method. PCR-Sanger sequencing was used to analyze the causative mutations in the five probands. PCR-high resolution melting (HRM) was developed to detect the identified mutations. A c.1138G>A mutation in exon 8 was found in 4 probands, while a c.1620C>G mutation was found in exon 11 of proband 5 whom had a mild phenotype. All patients were successfully distinguished from healthy controls with the PCR-HRM method. The results of HRM analysis were highly consistent with that of Sanger sequencing. The Gly380Arg and Asn540Lys are hot spot mutations of the FGFR3 gene among patients with ACH/HCH. PCR-HRM analysis is more efficient for detecting hot spot mutations of the FGFR3 gene.

  17. Detection of mismatch repair gene germline mutation carrier among Chinese population with colorectal cancer

    International Nuclear Information System (INIS)

    Jin, Hei-Ying; Zhao, Ronghua; Liu, Xiufang; Li, Vicky Ka Ming; Ding, Yijiang; Yang, Bolin; Geng, Jianxiang; Lai, Rensheng; Ding, Shuqing; Ni, Min

    2008-01-01

    Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominant syndrome. The National Cancer Institute (NCI) has recommended the Revised Bethesda guidelines for screening HNPCC. There has been a great deal of research on the value of these tests in other countries. However, literature about the Chinese population is scarce. Our objective is to detect and study microsatellite instability (MSI) and mismatch repair (MMR) gene germline mutation carriers among a Chinese population with colorectal cancer. In 146 prospectively recruited consecutive patients with clinically proven colorectal cancer, MSI carriers were identified by analysis of tumor tissue using multiplex fluorescence polymerase chain reaction (PCR) using the NCI recommended panel and classified into microsatellite instability-low (MSI-L), microsatellite instability-high (MSI-H) and microsatellite stable (MSS) groups. Immunohistochemical staining for MSH2, MSH6 and MLH1 on tissue microarrays (TMAs) was performed, and methylation of the MLH1 promoter was analyzed by quantitative methylation specific PCR (MSP). Germline mutation analysis of blood samples was performed for MSH2, MSH6 and MLH1 genes. Thirty-four out of the 146 colorectal cancers (CRCs, 23.2%) were MSI, including 19 MSI-H CRCs and 15 MSI-L CRCS. Negative staining for MSH2 was found in 8 CRCs, negative staining for MSH6 was found in 6 CRCs. One MSI-H CRC was negative for both MSH6 and MSH2. Seventeen CRCs stained negatively for MLH1. MLH1 promoter methylation was determined in 34 MSI CRCs. Hypermethylation of the MLH1 promoter occurred in 14 (73.7%) out of 19 MSI-H CRCs and 5 (33.3%) out of 15 MSI-L CRCs. Among the 34 MSI carriers and one MSS CRC with MLH1 negative staining, 8 had a MMR gene germline mutation, which accounted for 23.5% of all MSI colorectal cancers and 5.5% of all the colorectal cancers. Five patients harbored MSH2 germline mutations, and three patients harbored MSH6 germline mutations. None of the patients had an MLH

  18. Mutagenesis applied to improve fruit trees. Techniques, methods and evaluation of radiation-induced mutations

    International Nuclear Information System (INIS)

    Donini, B.

    1982-01-01

    Improvement of fruit tree cultivars is an urgent need for a modern and industrialized horticulture on which is based the economic importance of many countries. Both the cross breeding and the mutation breeding are regarded as the methods to be used for creating new varieties. Research carried out at the CNEN Agriculture Laboratory on mutagenesis to improve vegetatively propagated plants, under the FAO-IAEA Co-ordinated Research Programme, has dealt with methods of exposure, types of radiations, conditions during and after the irradiation, mechanisms of mutation induction, methodology of isolation of somatic mutations and evaluation of radiation-induced mutations in fruit trees. Problems associated with these aspects have been evaluated, which is very important for the more efficient use of radiation in the mutation breeding. Mutants of agronomical importance (plant size reduction, early ripening, fruit colour change, nectarine fruit, self-thinning fruit) have been isolated in cherry, grape, apple, olive and peach and they are ready to be released. (author)

  19. Effects of smoke and tea on radiation-induced bone marrow cell mutation and marrow inhibition

    International Nuclear Information System (INIS)

    Gao Yong; Zhang Weiguang

    2004-01-01

    Objective: To provide scientific information for the prevention and treatment of the radiation damage by analyzing the effects of smoke and tea on radiation-induced bone marrow cell mutation and marrow inhibition. Methods: 7 group mice were exposed to smoke and/or tea and/or radiation respectively. There were also b blank control group and a cyclophosphamide positive control group. The frequencies of micronucleated polychromatic erythrocytes (MPCE), the ratio of polychromatic erythrocytes (PCE) to mature erythrocytes (RBC) in marrow, and the count of peripheral blood hemoleukocyte were observed. Results: The frequencies of MPCE in the groups irradiated with γ-rays were significantly higher than that in the blank control group (P<0.05 or 0.01). The smoke + radiation group's frequency was significantly higher than single radiation group (P<0.05). The ratios of PCE to RBC in the groups irradiated were significantly lower than that in the blank control group (P<0.01). The counts of peripheral blood hemoleukocyte in the groups irradiated were significantly lower than the blank control group (P<0.01). Conclusion: Radiation were able to cause marrow cell mutation and induce marrow inhibition. Smoke increases the effect of radiation-induced marrow cell mutation. Tea and smoke could not affect radiation-induced bone marrow inhibition

  20. Radiation-induced cell mutations as a function of dose rate

    International Nuclear Information System (INIS)

    Kiefer, J.

    1987-01-01

    A brief review of the data in the literature is presented and forms the background of the experimental data given by the author obtained with exponential long-term cultures of V79 hamster cells exposed over a period of up to 35 days to different dose rates of gamma radiation. The experimental results show that at a dose rate of 40 mGy/hour the number of induced mutations is reduced, - which is in agreement with literature data - , but a dose rate of less than 30 mGy/hour makes the induced mutations leap to a value clearly higher than those induced by acute irradiation. As in addition to the mutations recombination is a significant factor of the radiation risk, experiments with a heterozygotic yeast strain have been made, as there is to date no reliable mammalian cell system available for this kind of research. Long-term radiation exposure of the yeast cells over a period of six weeks drastically increased the rate of recombinations, to a value higher by a factor of about 4 than that induced by acute irradiation. (orig.) [de

  1. Plant type improvement of indigenous rice cultivars through induced mutations

    International Nuclear Information System (INIS)

    Kihupi, A.

    1997-01-01

    A high yielding, locally adapted cultivar 'Afaa Mwanza 1/159' of rice (Oryza sativa L.) which is tall and late in maturity, was irradiated with gamma rays at doses of 170, 210 and 250 Gy to shorten plant height and time of maturity. Twelve mutants were selected, and evaluated for yield performance in field trials from M 6 to M 9 generations. All the mutants were shorter in plant height, and gave higher mean yield than the parent. Correlation coefficient analysis showed that the number of productive tillers, number of panicles per square meter and grain filling in the panicle were important characters which influenced yield. On the other hand, panicle length had negative influence on yield. Cv. 'Supa India' and 'Salama' were also irradiated with doses of 170, 210, 240 Gy gamma rays. Analysis of M 2 populations of these cultivars indicated that mutagenesis created a lot of variation in plant height, maturity, spikelet fertility and panicle length. The induced variation shall be useful in selecting desired plant types. (author). 16 refs, 12 tabs

  2. Plant type improvement of indigenous rice cultivars through induced mutations

    Energy Technology Data Exchange (ETDEWEB)

    Kihupi, A [Department of Crop Science and Production, Sokoine Univ. of Agriculture, Morogoro (Tanzania)

    1997-07-01

    A high yielding, locally adapted cultivar `Afaa Mwanza 1/159` of rice (Oryza sativa L.) which is tall and late in maturity, was irradiated with gamma rays at doses of 170, 210 and 250 Gy to shorten plant height and time of maturity. Twelve mutants were selected, and evaluated for yield performance in field trials from M{sub 6} to M{sub 9} generations. All the mutants were shorter in plant height, and gave higher mean yield than the parent. Correlation coefficient analysis showed that the number of productive tillers, number of panicles per square meter and grain filling in the panicle were important characters which influenced yield. On the other hand, panicle length had negative influence on yield. Cv. `Supa India` and `Salama` were also irradiated with doses of 170, 210, 240 Gy gamma rays. Analysis of M{sub 2} populations of these cultivars indicated that mutagenesis created a lot of variation in plant height, maturity, spikelet fertility and panicle length. The induced variation shall be useful in selecting desired plant types. (author). 16 refs, 12 tabs.

  3. Development of radiation-induced mutation techniques and functional genomics studies

    International Nuclear Information System (INIS)

    Kim, Dong Sub; Kang, Si Yong; Kim, Jin Baek

    2012-01-01

    This project has been performed to develop plant genetic resources using radiation (gamma-rays, ion-beam, space environments), to conduct functional genomics studies with mutant resources, and to develop new radiation plant breeding techniques using various radiation sources during 3 years. In the first section, we developed flower genetic resources, functional crop resources, and bio-industrial plant resources. In the second section, we cloned several mutated genes and studied mechanisms of gene expression and genetic diversity of mutations induced by gamma-rays. In the third section, we developed new plant breeding techniques using gamma-phytotron, heavy ion-beam, and space environments. Based on these results, a total of 8 cultivars containing Chrysanthemum, Hibiscus, kenaf, rice, and soybean were applied for plant variety protection (PVP) and a total of 4 cultivars were registered for PVP. Also, license agreement for the dwarf type Hibiscus mutant 'Ggoma' was conducted with Supro co. and the manufacturing technology for natural antioxidant pear-grape vinegar was transferred into Enzenic co. Also, 8 gene sequences, such as F3'H and LDOX genes associated with flower color in Chrysanthemum and EPSPS gene from Korean lawn grass, were registered in the database of National Center for Biotechnology Information (NCBI). In the future study, we will develop new radiation mutation breeding techniques through the mutation spectrum induced by various radiation sources, the studies for mechanism of the cellular response to radiation, and the comparative·structural·functional genomics studies for useful traits

  4. Analysis of mutations in the human HPRT gene induced by accelerated heavy-ion irradiation

    International Nuclear Information System (INIS)

    Kagawa, Yasuhiro; Yatagai, Fumio; Hanaoka, Fumio; Suzuki, Masao; Kase, Youko; Kobayashi, Akiko; Hirano, Masahiko; Kato, Takesi; Watanabe, Masami.

    1995-01-01

    Multiplex PCR analysis of HPRT(-) mutations in human embryo (HE) cells induced by 230 keV/μm carbon-ion irradiation showed no large deletion around the exon regions of the locus gene in contrast to the irradiations at different LETs. To identify these mutations, the sequence alterations in a cDNA of hprt gene were determined for 18 mutant clones in this study. Missing of exon 6 was the most frequent mutational event (10 clones), and missing of both exons 6 and 8 was next most frequent event (6 clones), then base substitutions (2 clones). These characteristics were not seen in a similar analysis of spontaneous mutations, which showed base substitution (5 clones), frameshift (2 clones), missing of both exons 2 and 3 (2 clones), and a single unidentified clone. Direct sequencing and restriction enzyme digestion of the genomic DNA of the mutants which showed missing of exons 6 and 8 in the cDNA, supports the possibility that they were induced by aberrant mRNA splicing. (author)

  5. Male-fertility-restorer mutation induced by x-rays in wheat

    International Nuclear Information System (INIS)

    Sasaki, Mutsuo; Nakata, Noboru; Yasumuro, Yoshimasa

    1982-01-01

    Some male-fertility restoring mutants were obtained by X-irradiation (20 or 25 kR, 105.3 R/min) of the air-dried seed of cytoplasmic male-sterile (cms) wheat, (timopheevi)-Bison. These X-ray induced male-fertility restoring mutant (Rfx) lines restored the male fertility of F 1 hybrids with cms (timopheevi)-Bison as female, but their fertility-restoring ability was not superior to that of known restorers such as Gironde, Primepi, and (t)-H30. The Rfx lines were also different from the original (timopheevi)-Bison, in many characters. The study on these multicharacter mutations with 18 morphological and physiological characters of the 7 M 6 line groups derived from the 7M 2 plants, revealed that each M 2 progenitor plant of each M 6 line-group had the mutant genes for almost all these characters, and that the mutation for at least half of all these mutant genes was induced in the original cell of the gamates of each X-irradiated M 1 plant. Considering the multicharacter mutations of the Rfx lines, a backcross method for the mutation breeding of male-fertility restorers in wheat was proposed. (Kaihara, S.)

  6. Deficiency of the DNA repair protein nibrin increases the basal but not the radiation induced mutation frequency in vivo

    International Nuclear Information System (INIS)

    Wessendorf, Petra; Vijg, Jan; Nussenzweig, André; Digweed, Martin

    2014-01-01

    Highlights: • lacZ mutant frequencies measured in vivo in mouse models of radiosensitive Nijmegen Breakage Syndrome. • Spontaneous mutation frequencies are increased in lymphatic tissue due to Nbn mutation. • Single base transitions, not deletions, dominate the mutation spectrum. • Radiation induced mutation frequencies are not increased due to Nbn mutation. - Abstract: Nibrin (NBN) is a member of a DNA repair complex together with MRE11 and RAD50. The complex is associated particularly with the repair of DNA double strand breaks and with the regulation of cell cycle check points. Hypomorphic mutation of components of the complex leads to human disorders characterised by radiosensitivity and increased tumour occurrence, particularly of the lymphatic system. We have examined here the relationship between DNA damage, mutation frequency and mutation spectrum in vitro and in vivo in mouse models carrying NBN mutations and a lacZ reporter plasmid. We find that NBN mutation leads to increased spontaneous DNA damage in fibroblasts in vitro and high basal mutation rates in lymphatic tissue of mice in vivo. The characteristic mutation spectrum is dominated by single base transitions rather than the deletions and complex rearrangements expected after abortive repair of DNA double strand breaks. We conclude that in the absence of wild type nibrin, the repair of spontaneous errors, presumably arising during DNA replication, makes a major contribution to the basal mutation rate. This applies also to cells heterozygous for an NBN null mutation. Mutation frequencies after irradiation in vivo were not increased in mice with nibrin mutations as might have been expected considering the radiosensitivity of NBS patient cells in vitro. Evidently apoptosis is efficient, even in the absence of wild type nibrin

  7. Deficiency of the DNA repair protein nibrin increases the basal but not the radiation induced mutation frequency in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Wessendorf, Petra [Institute of Medical and Human Genetics, Charité – Universitätsmedizin Berlin, Augustenburger Platz 1, D-13353 Berlin (Germany); Vijg, Jan [Albert Einstein College of Medicine, Michael F. Price Center, 1301 Morris Park Avenue, Bronx, NY 10461 (United States); Nussenzweig, André [Laboratory of Genome Integrity, National Cancer Institute, National Institute of Health, 37 Convent Drive, Room 1106, Bethesda, MD 20892 (United States); Digweed, Martin, E-mail: martin.digweed@charite.de [Institute of Medical and Human Genetics, Charité – Universitätsmedizin Berlin, Augustenburger Platz 1, D-13353 Berlin (Germany)

    2014-11-15

    Highlights: • lacZ mutant frequencies measured in vivo in mouse models of radiosensitive Nijmegen Breakage Syndrome. • Spontaneous mutation frequencies are increased in lymphatic tissue due to Nbn mutation. • Single base transitions, not deletions, dominate the mutation spectrum. • Radiation induced mutation frequencies are not increased due to Nbn mutation. - Abstract: Nibrin (NBN) is a member of a DNA repair complex together with MRE11 and RAD50. The complex is associated particularly with the repair of DNA double strand breaks and with the regulation of cell cycle check points. Hypomorphic mutation of components of the complex leads to human disorders characterised by radiosensitivity and increased tumour occurrence, particularly of the lymphatic system. We have examined here the relationship between DNA damage, mutation frequency and mutation spectrum in vitro and in vivo in mouse models carrying NBN mutations and a lacZ reporter plasmid. We find that NBN mutation leads to increased spontaneous DNA damage in fibroblasts in vitro and high basal mutation rates in lymphatic tissue of mice in vivo. The characteristic mutation spectrum is dominated by single base transitions rather than the deletions and complex rearrangements expected after abortive repair of DNA double strand breaks. We conclude that in the absence of wild type nibrin, the repair of spontaneous errors, presumably arising during DNA replication, makes a major contribution to the basal mutation rate. This applies also to cells heterozygous for an NBN null mutation. Mutation frequencies after irradiation in vivo were not increased in mice with nibrin mutations as might have been expected considering the radiosensitivity of NBS patient cells in vitro. Evidently apoptosis is efficient, even in the absence of wild type nibrin.

  8. Fragment length analysis screening for detection of CEBPA mutations in intermediate-risk karyotype acute myeloid leukemia.

    Science.gov (United States)

    Fuster, Oscar; Barragán, Eva; Bolufer, Pascual; Such, Esperanza; Valencia, Ana; Ibáñez, Mariam; Dolz, Sandra; de Juan, Inmaculada; Jiménez, Antonio; Gómez, Maria Teresa; Buño, Ismael; Martínez, Joaquín; Cervera, José; Montesinos, Pau; Moscardó, Federico; Sanz, Miguel Ángel

    2012-01-01

    During last years, molecular markers have been increased as prognostic factors routinely screened in acute myeloid leukemia (AML). Recently, an increasing interest has been reported in introducing to clinical practice screening for mutations in the CCAAT/enhancer-binding protein α (CEBPA) gene in AML, as it seems to be a good prognostic factor. However, there is no reliable established method for assessing CEBPA mutations during the diagnostic work-up of AMLs. We describe here a straightforward and reliable fragment analysis method based in PCR capillary electrophoresis (PCR-CE) for screening of CEBPA mutations; moreover, we present the results obtained in 151 intermediate-risk karyotype AML patients (aged 16-80 years). The method gave a specificity of 100% and sensitivity of 93% with a lower detection limit of 1-5% for CEBPA mutations. The series found 19 mutations and four polymorphisms in 12 patients, seven of whom (58%) presented two mutations. The overall frequency of CEBPA mutations in AML was 8% (n = 12). CEBPA mutations showed no coincidence with FLT3-ITD or NPM1 mutations. CEBPA mutation predicted better disease-free survival in the group of patients without FLT3-ITD, NPM, or both genes mutated (HR 3.6, IC 95%; 1.0-13.2, p = 0.05) and better overall survival in patients younger than 65 of this group without molecular markers (HR 4.0, IC 95%; 1.0-17.4, p = 0.05). In conclusion, the fragment analysis method based in PCR-CE is a rapid, specific, and sensitive method for CEBPA mutation screening and our results confirm that CEBPA mutations can identify a subgroup of patients with favorable prognosis in AML with intermediate-risk karyotype.

  9. Establishment and application of a multiplex genetic mutation-detection method of lung cancer based on MassARRAY platform

    International Nuclear Information System (INIS)

    Tian, Hong-Xia; Zhang, Xu-Chao; Wang, Zhen; Chen, Jian-Guang; Chen, Shi-Liang; Guo, Wei-Bang; Wu, Yi-Long

    2016-01-01

    Objective: This study aims to establish a method for highly parallel multiplexed detection of genetic mutations in Chinese lung cancer samples through Agena iPLEX chemistry and matrix-assisted laser desorption ionization time-of-flight analysis on MassARRAY mass spectrometry platform. Methods: We reviewed the related literature and data on lung cancer treatments. We also identified 99 mutation hot spots in 13 target genes closely related to the pathogenesis, drug resistance, and metastasis of lung cancer. A total of 297 primers, composed of 99 paired forward and reverse amplification primers and 99 matched extension primers, were designed using Assay Design software. The detection method was established by analyzing eight cell lines and six lung cancer specimens. The proposed method was then validated through comparisons by using a LungCarta TM kit. The sensitivity and specificity of the proposed method were evaluated by directly sequencing EGFR and KRAS genes in 100 lung cancer cases. Results: The proposed method was able to detect multiplex genetic mutations in lung cancer cell lines. This finding was consistent with the observations on previously reported mutations. The proposed method can also detect such mutations in clinical lung cancer specimens. This result was consistent with the observations with LungCarta TM kit. However, an FGFR2 mutation was detected only through the proposed method. The measured sensitivity and specificity were 100% and 96.3%, respectively. Conclusions: The proposed MassARRAY technology-based multiplex method can detect genetic mutations in Chinese lung cancer patients. Therefore, the proposed method can be applied to detect mutations in other cancer tissues

  10. Age-related increase in the rate of spontaneou and γ-ray-induced hprt mutations in mouse spleen lymphocytes

    International Nuclear Information System (INIS)

    Gazlev, A.I.; Podlutskii, A.Ya.; Bradbury, R.

    1994-01-01

    Endogenous and exogenous factors continually afflict DNA of cells of organisms. A certain amount of the damage is accumulated causing mutations, increasing the risk of malignacies, impairing cell functions, and upsetting the body's homeostasis. The research reported here studies the rates of spontaneous hprt nmutationsand those induced you ggammairradiation in the splenocytes of mice at various ages. The rate of spontaneous and induced hprt gene mutations increases with aging. In gamma irradiated mice the rate of radiation-induced mutations depended on the absorbed dose and age, with the rate 2.3-3.0 fold higher in 104-110 week old mice than in younger pups. 15 refs., 1 tab

  11. Somatic mutation and recombination induced with reactor thermal neutrons in Drosophila melanogaster

    International Nuclear Information System (INIS)

    Zambrano A, F.; Guzman R, J.; Paredes G, L.; Delfin L, A.

    1997-01-01

    The SMART test of Drosophila melanogaster was used to quantify the effect over the somatic mutation and recombination induced by thermal and fast neutrons at the TRIGA Mark III reactor of the ININ at the power of 300 k W for times of 30, 60 and 120 minutes with total equivalent doses respectively of 20.8, 41.6 and 83.2 Sv. A linear relation between the radiation equivalent dose and the frequency of the genetic effects such as mutation and recombination was observed. The obtained results allow to conclude that SMART is a sensitive system to the induced damage by neutrons, so this can be used for studying its biological effects. (Author)

  12. Non-invasive detection of urothelial cancer through the analysis of driver gene mutations and aneuploidy

    Science.gov (United States)

    Li, Lu; Douville, Christopher; Wang, Yuxuan; Cohen, Joshua David; Taheri, Diana; Silliman, Natalie; Schaefer, Joy; Ptak, Janine; Dobbyn, Lisa; Papoli, Maria; Kinde, Isaac; Afsari, Bahman; Tregnago, Aline C; Bezerra, Stephania M; VandenBussche, Christopher; Fujita, Kazutoshi; Ertoy, Dilek; Cunha, Isabela W; Yu, Lijia; Bivalacqua, Trinity J; Grollman, Arthur P; Diaz, Luis A; Karchin, Rachel; Danilova, Ludmila; Huang, Chao-Yuan; Shun, Chia-Tung; Turesky, Robert J; Yun, Byeong Hwa; Rosenquist, Thomas A; Pu, Yeong-Shiau; Hruban, Ralph H; Tomasetti, Cristian; Papadopoulos, Nickolas; Kinzler, Ken W

    2018-01-01

    Current non-invasive approaches for detection of urothelial cancers are suboptimal. We developed a test to detect urothelial neoplasms using DNA recovered from cells shed into urine. UroSEEK incorporates massive parallel sequencing assays for mutations in 11 genes and copy number changes on 39 chromosome arms. In 570 patients at risk for bladder cancer (BC), UroSEEK was positive in 83% of those who developed BC. Combined with cytology, UroSEEK detected 95% of patients who developed BC. Of 56 patients with upper tract urothelial cancer, 75% tested positive by UroSEEK, including 79% of those with non-invasive tumors. UroSEEK detected genetic abnormalities in 68% of urines obtained from BC patients under surveillance who demonstrated clinical evidence of recurrence. The advantages of UroSEEK over cytology were evident in low-grade BCs; UroSEEK detected 67% of cases whereas cytology detected none. These results establish the foundation for a new non-invasive approach for detection of urothelial cancer. PMID:29557778

  13. Molecular analysis of radiation-induced albino (c)-locus mutations that cause death at preimplantation stages of development

    International Nuclear Information System (INIS)

    Rinchik, E.M.; Toenjes, R.R.; Paul, D.; Potter, M.D.

    1993-01-01

    Deletion mutations at the albino (c) locus have been useful for continuing the development of fine-structure physical and functional maps of the Fes-Hbb region of mouse chromosome 7. This report describes the molecular analysis of a number of radiation-induced c deletions that, when homozygous, cause death of the embryo during preimplantation stages. The distal extent of these deletions defines a locus, pid, (preimplantation development) genetically associated with this phenotype. The proximal breakpoints of eight of these deletions were mapped with respect to the Tyr (tyrosinase; albino) gene as well as to anonymous loci within the Fah-Tyr region that are defined by the Pmv-31 viral integration site and by chromosome-microdissection clones. Rearrangements corresponding to the proximal breakpoints of two of these deletions were detected by Southern blot analysis, and a size-altered restriction fragment carrying the breakpoint of one of them was cloned. A probe derived from this deletion fusion fragment defines a locus, D7Rn6, which maps within (or distal to) the pid region, and which discriminates among the distal extents of deletions eliciting the pid phenotype. Extension of physical maps from D7Rn6 should provide access both to the pid region and to loci mapping distal to pid that are defined by N-ethyl-N-nitrosourea-induced lethal mutations. 36 refs., 10 figs

  14. Mutations in BALB mitochondrial DNA induce CCL20 up-regulation promoting tumorigenic phenotypes

    Energy Technology Data Exchange (ETDEWEB)

    Sligh, James [Department of Medicine—Dermatology Division, University of Arizona, Tucson, AZ 857 24 (United States); University of Arizona Cancer Center, Tucson, AZ 85724 (United States); Janda, Jaroslav [University of Arizona Cancer Center, Tucson, AZ 85724 (United States); Jandova, Jana, E-mail: jjandova@email.arizona.edu [Department of Medicine—Dermatology Division, University of Arizona, Tucson, AZ 857 24 (United States); University of Arizona Cancer Center, Tucson, AZ 85724 (United States)

    2014-11-15

    Highlights: • Alterations in mitochondrial DNA are commonly found in various human cancers. • Mutations in BALB mitochondrial DNA induce up-regulation of chemokine CCL20. • Increased growth and motility of mtBALB cells is associated with CCL20 levels. • mtDNA changes in BALB induce in vivo tumor growth through CCL20 up-regulation. • Mutations in mitochondrial DNA play important roles in keratinocyte neoplasia. - Abstract: mtDNA mutations are common in human cancers and are thought to contribute to the process of neoplasia. We examined the role of mtDNA mutations in skin cancer by generating fibroblast cybrids harboring a mutation in the gene encoding the mitochondrial tRNA for arginine. This somatic mutation (9821insA) was previously reported in UV-induced hyperkeratotic skin tumors in hairless mice and confers specific tumorigenic phenotypes to mutant cybrids. Microarray analysis revealed and RT-PCR along with Western blot analysis confirmed the up-regulation of CCL20 and its receptor CCR6 in mtBALB haplotype containing the mt-Tr 9821insA allele compared to wild type mtB6 haplotype. Based on reported role of CCL20 in cancer progression we examined whether the hyper-proliferation and enhanced motility of mtBALB haplotype would be associated with CCL20 levels. Treatment of both genotypes with recombinant CCL20 (rmCCL20) resulted in enhanced growth and motility of mtB6 cybrids. Furthermore, the acquired somatic alteration increased the in vivo tumor growth of mtBALB cybrids through the up-regulation of CCL20 since neutralizing antibody significantly decreased in vivo tumor growth of these cells; and tumors from anti-CCL20 treated mice injected with mtBALB cybrids showed significantly decreased CCL20 levels. When rmCCL20 or mtBALB cybrids were used as chemotactic stimuli, mtB6 cybrids showed increased motility while anti-CCL20 antibody decreased the migration and in vivo tumor growth of mtBALB cybrids. Moreover, the inhibitors of MAPK signaling and NF

  15. Molecular analysis of two mouse dilute locus deletion mutations: Spontaneous dilute lethal20J and radiation-induced dilute prenatal lethal Aa2 alleles

    International Nuclear Information System (INIS)

    Strobel, M.C.; Seperack, P.K.; Copeland, N.G.; Jenkins, N.A.

    1990-01-01

    The dilute (d) coat color locus of mouse chromosome 9 has been identified by more than 200 spontaneous and mutagen-induced recessive mutations. With the advent of molecular probes for this locus, the molecular lesion associated with different dilute alleles can be recognized and precisely defined. In this study, two dilute mutations, dilute-lethal20J (dl20J) and dilute prenatal lethal Aa2, have been examined. Using a dilute locus genomic probe in Southern blot analysis, we detected unique restriction fragments in dl20J and Aa2 DNA. Subsequent analysis of these fragments showed that they represented deletion breakpoint fusion fragments. DNA sequence analysis of each mutation-associated deletion breakpoint fusion fragment suggests that both genomic deletions were generated by nonhomologous recombination events. The spontaneous dl20J mutation is caused by an interstitial deletion that removes a single coding exon of the dilute gene. The correlation between this discrete deletion and the expression of all dilute-associated phenotypes in dl20J homozygotes defines the dl20J mutation as a functional null allele of the dilute gene. The radiation-induced Aa2 allele is a multilocus deletion that, by complementation analysis, affects both the dilute locus and the proximal prenatal lethal-3 (pl-3) functional unit. Molecular analysis of the Aa2 deletion breakpoint fusion fragment has provided access to a previously undefined gene proximal to d. Initial characterization of this new gene suggests that it may represent the genetically defined pl-3 functional unit

  16. Enzyme-activity mutations detected in mice after paternal fractionated irradiation

    International Nuclear Information System (INIS)

    Charles, D.J.; Pretsch, W.

    1986-01-01

    (101/E1 X C3H/E1)F 1 -hybrid male mice were exposed in a 24-h fractionation interval to either 3.0 + 3.0-Gy or 5.1 + 5.1-Gy X-irradiation, and mated to untreated Test-stock females. The offspring were examined for mutations at 7 recessive specific loci and for activity alterations of erythrocyte enzymes controlled presumably by 12 loci. No enzyme-activity mutant was found in 3610 F 1 -offspring of the control group. In the experimental groups, no mutant was detected in 533 (3.0 + 3.0 Gy) and 173 (5.1 + 5.1 Gy) offspring from postspermatogonial germ cells treated. After treatment of spermatogonia, 1 mutant in 3388 F 1 -offspring of the 3.0 + 3.0-Gy group, and 5 mutants in 3187 F 1 offspring of the 5.1 + 5.1-Gy group were found. The mutants were all genetically confirmed. The frequency (expressed as mutants/locus/gamete) of enzyme-activity mutations is 2 (5.1 + 5.1-Gy group) to 10 (3.0 + 3.0-Gy group) times lower than the frequency of recessive specific-locus mutations. (Auth.)

  17. A New Generalizable Test for Detection of Mutations Affecting Tn10 Transposition

    OpenAIRE

    Huisman, Olivier; Kleckner, Nancy

    1987-01-01

    We describe here a new rapid screen that allows easy detection of transposon or host mutations that affect Tn10 transposition in Escherichia coli. This test involves a new Tn10 derivative called the "mini-lacZ-kanR fusion hopper" or mini-Tn10-LK for short. This element does not direct expression of β-galactosidase when present at its original starting location on a suitably engineered plasmid or phage genome because it lacks appropriate transcription and translation start signals. However, t...

  18. A population genetic analysis of the potential for a crude oil spill to induce heritable mutations and impact natural populations

    Energy Technology Data Exchange (ETDEWEB)

    Cronin, M.A. [LGL Alaska Research Associates Inc., Anchorage, AK (United States); Bickham, J.W. [Texas A and M University, College Station, TX (United States). Dept. of Wildlife and Fisheries Sciences; LGL Ecological Genetics Inc., Bryan, TX (United States)

    1998-07-01

    The primary environmental impact following an oil spill typically is acute toxicity to fish and wildlife. However, multigenerational effects through toxicant-induced heritable mutations might also occur. Some polycyclic aromatic hydrocarbon (PAH) components of crude oil are potentially mutagenic, although specific components and doses that induce mutations are poorly known. We applied population genetics concepts to assess the extent of mortality and the persistence of deleterious heritable mutations resulting from exposure to potential mutagens, such as crude oil. If lethal mutations are induced, the population will experience some mortality, but the mutations are quickly removed or reduced to low frequency by natural selection. This occurs within one or a few generations when mutations are dominant or partially recessive. Totally recessive alleles persist in low frequency for many generations, but result in relatively little impact on the population, depending on the number of mutated loci. We also applied population genetics concepts to assess the potential for heritable mutations induced by the Exxon Valdez oil spill in Prince William Sound, Alaska, to affect pink salmon populations. We stress that breeding units (e.g., streams with distinct spawning populations of salmon) must be considered individually to assess heritable genetic effects. For several streams impacted by the oil spill, there is inconsistency between observed egg mortality and that expected if lethal heritable mutations had been induced by exposure to crude oil. Observed mortality was either higher or lower than expected depending on the spawning population, year, and cohort considered. Any potential subtle effect of lethal mutations induced by the Exxon Valdez oil spill is overridden by natural environmental variation among spawning areas. We discuss the need to focus on population-level effects in toxicological assessments because fish and wildlife management focuses on populations, not

  19. Lack of chemically induced mutation in repair-deficient mutants of yeast

    International Nuclear Information System (INIS)

    Prakash, L.

    1974-01-01

    Two genes, rad6 and rad9, that confer radiation sensitivity in the yeast Saccharomyces cerevisiae also greatly reduce the frequency of chemically-induced reversions of a tester mutant cyc1-131, which is a chain initiation mutant in the structural gene determining iso-1-cytochrome c. Mutations induced by ethyl methanesulfonate (EMS), diethyl sulfate (DES), methyl methanesulfonate (MMS), dimethyl sulfate (DMS), nitroquinoline oxide (NQO), nitrosoguanidine (NTG), nitrogen mustard (HN2), β-propiolactone, and tritiated uridine, as well as mutations induced by ultraviolet light (UV) and ionizing radiation were greatly diminished in strains homozygous for either the rad6 or rad9 gene. Nitrous acid and nitrosoimidazolidone (NIL), on the other hand, were highly mutagenic in these repair-deficient mutants, and at low doses, these mutagens acted with about the same efficiency as in the normal RAD strain. At high doses of either nitrous acid or NIL, however, reversion frequencies were significantly reduced in the two rad mutants compared to normal strains. Although both rad mutants are immutable to about the same extent, the rad9 strains tend to be less sensitive to the lethal effect of chemical mutagens than rad6 strains. It is concluded that yeast requires a functional repair system for mutation induction by chemical agents. (auth)

  20. Lack of chemically induced mutation in repair-deficient mutants of yeast.

    Science.gov (United States)

    Prakash, L

    1974-12-01

    Two genes, rad6 and rad9, that confer radiation sensitivity in the yeast Saccharomyces cerevisiae also greatly reduce the frequency of chemically-induced reversions of a tester mutant cyc1-131, which is a chain initiation mutant in the structural gene determining iso-1-cytochrome c. Mutations induced by ethyl methanesulfonate (EMS), diethyl sulfate (DES), methyl methanesulfonate (MMS), dimethyl sulfate (DMS), nitroquinoline oxide (NQO), nitrosoguanidine (NTG), nitrogen mustard (HN2), beta-propiolactone, and tritiated uridine, as well as mutations induced by ultraviolet light (UV) and ionizing radiation were greatly diminished in strains homozygous for either the rad6 or rad9 gene. Nitrous acid and nitrosoimidazolidone (NIL), on the other hand, were highly mutagenic in these repair-deficient mutants, and at low doses, these mutagens acted with about the same efficiency as in the normal RAD strain. At high doses of either nitrous acid or NIL, however, reversion frequencies were significantly reduced in the two rad mutants compared to normal strains. Although both rad mutants are immutable to about the same extent, the rad9 strains tend to be less sensitive to the lethal effect of chemical mutagens than rad6 strains. It is concluded that yeast requires a functional repair system for mutation induction by chemical agents.

  1. Few molecule SERS detection using nanolens based plasmonic nanostructure: application to point mutation detection

    KAUST Repository

    Das, Gobind

    2016-10-27

    Advancements in nanotechnology fabrication techniques allow the possibility to design and fabricate a device with a minimum gap (<10 nm) between the composing nanostructures in order to obtain better control over the creation and spatial definition of plasmonic hot-spots. The present study is intended to show the fabrication of nanolens and their application to single/few molecules detection. Theoretical simulations were performed on different designs of real structures, including comparison of rough and smooth surfaces. Various molecules (rhodamine 6G, benzenethiol and BRCA1/BRCT peptides) were examined in this regard. Single molecule detection was possible for synthetic peptides, with a possible application in early detection of diseases. © The Royal Society of Chemistry.

  2. Few molecule SERS detection using nanolens based plasmonic nanostructure: application to point mutation detection

    KAUST Repository

    Das, Gobind; Alrasheed, Salma; Coluccio, Maria Laura; Gentile, Francesco; Nicastri, Annalisa; Candeloro, Patrizio; Cuda, Giovanni; Perozziello, Gerardo; Di Fabrizio, Enzo M.

    2016-01-01

    Advancements in nanotechnology fabrication techniques allow the possibility to design and fabricate a device with a minimum gap (<10 nm) between the composing nanostructures in order to obtain better control over the creation and spatial definition of plasmonic hot-spots. The present study is intended to show the fabrication of nanolens and their application to single/few molecules detection. Theoretical simulations were performed on different designs of real structures, including comparison of rough and smooth surfaces. Various molecules (rhodamine 6G, benzenethiol and BRCA1/BRCT peptides) were examined in this regard. Single molecule detection was possible for synthetic peptides, with a possible application in early detection of diseases. © The Royal Society of Chemistry.

  3. [Mutants of the yeast Saccharomyces cerevisiae characterized by enhanced induced mutagenesis. III. Effect of the him mutation on the effectiveness and specificity of UF-induced mutagenesis].

    Science.gov (United States)

    Ivanov, E L; Koval'tsova, S V; Korolev, V G

    1987-09-01

    We have studied the influence of him1-1, him2-1, him3-1 and himX mutations on induction frequency and specificity of UV-induced adenine-dependent mutations in the yeast Saccharomyces cerevisiae. Him mutations do not render haploid cells more sensitive to the lethal action of UV-light; however, in him strains adenine-dependent mutations (ade1, ade2) were induced more frequently (1.5--2-fold), as compared to the HIM strain. An analysis of the molecular nature of ade2 mutants revealed that him1-1, him2-1 and himX mutations increase specifically the yield of transitions (AT----GC and GC----AT), whereas in the him3-1 strain the yield of transversions was enhanced as well. We suggest him mutations analysed to affect specific repair pathway for mismatch correction.

  4. Detection of new paternal dystrophin gene mutations in isolated cases of dystrophinopathy in females

    Energy Technology Data Exchange (ETDEWEB)

    Pegoraro, E.; Wessel, H.B.; Schwartz, L.; Hoffman, E.P. (Univ. of Pittsburgh, PA (United States)); Schimke, R.N. (Kansas Univ. Medical Center, Kansas City (United States)); Arahata, Kiichi; Hayashi, Yukiko (National Institute of Neurosciences, Tokyo (Japan)); Stern, H. (Children' s National Medical Center, Washington, DC (United States)); Marks, H. (A.I. duPont Institute, Wilmington (United States)); Glasberg, M.R. (Henry Ford Hospital, Detroit, MI (United States)) (and others)

    1994-06-01

    Duchenne muscular dystrophy is one of the most common lethal monogenic disorders and is caused by dystrophin deficiency. The disease is transmitted as an X-linked recessive trait; however, recent biochemical and clinical studies have shown that many girls and women with a primary myopathy have an underlying dystrophinopathy, despite a negative family history for Duchenne dystrophy. These isolated female dystrophinopathy patients carried ambiguous diagnoses with presumed autosomal recessive inheritance (limb-girdle muscular dystrophy) prior to biochemical detection of dystrophin abnormalities in their muscle biopsy. It has been assumed that these female dystrophinopathy patients are heterozygous carries who show preferential inactivation of the X chromosome harboring the normal dystrophin gene, although this has been shown for only a few X:autosome translocations and for two cases of discordant monozygotic twin female carriers. Here the authors study X-inactivation patterns of 13 female dystrophinopathy patients - 10 isolated cases and 3 cases with a positive family history for Duchenne dystrophy in males. They show that all cases have skewed X-inactivation patterns in peripheral blood DNA. Of the nine isolated cases informative in the assay, eight showed inheritance of the dystrophin gene mutation from the paternal germ line. Only a single case showed maternal inheritance. The 10-fold higher incidence of paternal transmission of dystrophin gene mutations in these cases is at 30-fold variance with Bayesian predictions and gene mutation rates. Thus, the results suggest some mechanistic interaction between new dystrophin gene mutations, paternal inheritance, and skewed X inactivation. The results provide both empirical risk data and a molecular diagnostic test method, which permit genetic counseling and prenatal diagnosis of this new category of patients. 58 refs., 7 figs., 2 tabs.

  5. X-ray-induced bystander response reduce spontaneous mutations in V79 cells

    International Nuclear Information System (INIS)

    Maeda, Munetoshi; Kobayashi, Katsumi; Matsumoto, Hideki; Usami, Noriko; Tomiya, Masanori

    2013-01-01

    The potential for carcinogenic risks is increased by radiation-induced bystander responses; these responses are the biological effects in unirradiated cells that receive signals from the neighboring irradiated cells. Bystander responses have attracted attention in modern radiobiology because they are characterized by non-linear responses to low-dose radiation. We used a synchrotron X-ray microbeam irradiation system developed at the Photon Factory, High Energy Accelerator Research Organization, KEK, and showed that nitric oxide (NO)-mediated bystander cell death increased biphasically in a dose-dependent manner. Here, we irradiated five cell nuclei using 10 × 10 µm 2 5.35 keV X-ray beams and then measured the mutation frequency at the hypoxanthine-guanosine phosphoribosyl transferase (HPRT) locus in bystander cells. The mutation frequency with the null radiation dose was 2.6 × 10 -5 (background level), and the frequency decreased to 5.3 × 10 -6 with a dose of approximately 1 Gy (absorbed dose in the nucleus of irradiated cells). At high doses, the mutation frequency returned to the background level. A similar biphasic dose-response effect was observed for bystander cell death. Furthermore, we found that incubation with 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (carboxy-PTIO), a specific scavenger of NO, suppressed not only the biphasic increase in bystander cell death but also the biphasic reduction in mutation frequency of bystander cells. These results indicate that the increase in bystander cell death involves mechanisms that suppress mutagenesis. This study has thus shown that radiation-induced bystander responses could affect processes that protect the cell against naturally occurring alterations such as mutations. (author)

  6. UVA-induced mutational spectra in the laci gene from transgenic mouse skin

    International Nuclear Information System (INIS)

    Gorelick, N.J.; O'Kelly, J.A.; Biedermann, K.A.

    1995-01-01

    The UVB (295-320 nm) component of sunlight was once thought to be the sole cause of photoaging and skin cancer. However, there is now compelling evidence to suggest that chronic irradiation with UVA (320-400 nm) is a significant component of the etiologies of these diseases. To identify acute markers of UVA damage, we investigated UVA-induced mutagenesis in vivo by using a lacI transgenic mouse mutation assay. The backs of adult female C57BL/6 Big Blue reg-sign mice were shaved and exposed daily to a low or a high dose of UVA for 5 consecutive days. One group remained unexposed. The high dose of UVA significantly increased the mutant frequency in skin determined 12 days after the last exposure. Mutant frequencies were (Avg ± SEM, n=7-8/group): 6.1 ± 0.5 x 10 -5 (high dose). DNA sequence analysis of mutant lacI genes demonstrated that the high dose of UVA produced a different mutational spectrum compared to control. The mutational spectrum from the low dose mutants was not different from the control spectrum in skin generated previously; the predominant classes of recovered mutations were GC→At transitions at CpG sites (11/35) and GC →TA transversions (12/35). In contrast, in the high dose group, GC →AT transitions at non-CpG sites predominated (61/97 mutations); three tandem base substitutions (1 GG →AA; 2 CC→TT) were uniquely recovered; and an increased frequency of recovered GC→CG substitutions was observed (12/97 vs. none in controls). The recovered high dose spectrum is consistent with the types of DNA damage generated by UVA as well as by reactive oxygen species. These studies demonstrate that UVA is mutagenic in vivo and that this assay can be used to study early events in UVA-induced skin damage

  7. Evolution of high yielding chickpea varieties, having improved plant type and disease resistance, through induced mutations

    International Nuclear Information System (INIS)

    Sadiq, M.; Hussan, M.; Haq, M.A.

    1989-01-01

    The breeding programme on the use of induced mutations, in chickpea for genetic variability for better plant type, grain yield and disease resistance has been started. The chickpea mutant variety is one of the leading varieties being extensively grown throughout Pakistan and has played its role in stabilizing the chickpea production in the country. Four chickpea varieties were treated, each with two dosed of gamma rays. The main purpose of the mutagenic treatment of these varieties/cultivars, was induce multiple resistance. (A.B.)

  8. A Biofunctional Molecular Beacon for Detecting Single Base Mutations in Cancer Cells

    Directory of Open Access Journals (Sweden)

    Haiyan Dong

    2016-01-01

    Full Text Available The development of a convenient and sensitive biosensing system to detect specific DNA sequences is an important issue in the field of genetic disease therapy. As a classic DNA detection technique, molecular beacon (MB is often used in the biosensing system. However, it has intrinsic drawbacks, including high assay cost, complicated chemical modification, and operational complexity. In this study, we developed a simple and cost-effective label-free multifunctional MB (LMMB by integrating elements of polymerization primer, template, target recognition, and G-quadruplex into one entity to detect target DNA. The core technique was accomplished by introducing a G-hairpin that features fragments of both G-quadruplex and target DNA recognition in the G-hairpin stem. Hybridization between LMMB and target DNA triggered conformational change between the G-hairpin and the common C-hairpin, resulting in significant SYBR-green signal amplification. The hybridization continues to the isothermal circular strand-displacement polymerization and accumulation of the double-stranded fragments, causing the uninterrupted extension of the LMMB without a need of chemical modification and other assistant DNA sequences. The novel and programmable LMMB could detect target DNA with sensitivity at 250 pmol/l with a linear range from 2 to 100 nmol/l and the relative standard deviation of 7.98%. The LMMB could sense a single base mutation from the normal DNA, and polymerase chain reaction (PCR amplicons of the mutant-type cell line from the wild-type one. The total time required for preparation and assaying was only 25 minutes. Apparently, the LMMB shows great potential for detecting DNA and its mutations in biosamples, and therefore it opens up a new prospect for genetic disease therapy.

  9. Effect of genes controlling radiation sensitivity on chemically induced mutations in Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Prakash, L.

    1976-01-01

    The effect of 16 different genes (rad) conferring radiation sensitivity on chemically induced reversion in the yeast Saccharomyces cerevisiae was determined. The site of reversion used was a well-defined chain initiation mutant mapping in the structural gene coding for iso-1-cytochrome c. High doses of EMS and HNO 2 resulted in decreased reversion of cyc1-131 in rad6, rad9 and rad15 strains compared to the normal RAD + strains. In addition, rad52 greatly decreased EMS reversion of cyc1-131 but had no effect on HNO 2 -induced reversion; rad18, on the other hand, increased HNO 2 -induced reversion but did not alter EMS-induced reversion. When NQO was used as the mutagen, every rad gene tested, except for rad18, had an effect on reversion; rad6, rad9, rad15, rad17, rad18, rad22, rev1, rev2, and rev3 lowered NQO reversion while rad1, rad2, rad3, rad4, rad10, rad12, and rad16 increased it compared to the RAD + strain. The effect of rad genes on chemical mutagenesis is discussed in terms of their effect on uv mutagenesis. It is concluded that although the nature of the repair pathways may differ for uv- and chemically-induced mutations in yeast, a functional repair system is required for the induction of mutation by the chemical agents NQO, EMS, and HNO 2

  10. X-ray-induced mutations in Escherichia coli K-12 strains with altered DNA polymerase I activities

    International Nuclear Information System (INIS)

    Nagata, Yuki; Kawata, Masakado; Komura, Jun-ichiro; Ono, Tetsuya; Yamamoto, Kazuo

    2003-01-01

    Spectra of ionizing radiation mutagenesis were determined by sequencing X-ray-induced endogenous tonB gene mutations in Escherichia coli polA strains. We used two polA alleles, the polA1 mutation, defective for Klenow domain, and the polA107 mutation, defective for flap domain. We demonstrated that irradiation of 75 and 50 Gy X-rays could induce 3.8- and 2.6-fold more of tonB mutation in polA1 and polA107 strains, respectively, than spontaneous level. The radiation induced spectrum of 51 tonB mutations in polA1 and 51 in polA107 indicated that minus frameshift, A:T→T:A transversion and G:C→T:A transversion were the types of mutations increased. Previously, we have reported essentially the same X-ray-induced tonB mutation spectra in the wild-type strain. These results indicate that (1) X-rays can induce minus frameshift, A:T→T:A transversion and G:C→T:A transversion in E. coli and (2) presence or absence of polymerase I (PolI) of E. coli does not have any effects on the process of X-ray mutagenesis

  11. Capillary electrophoresis fragment analysis and clone sequencing in detection of dynamic mutations of spinocerebellar ataxia

    Directory of Open Access Journals (Sweden)

    Yuan-yuan CHEN

    2018-04-01

    Full Text Available Objective To estimate the accuracy and stability of capillary electrophoresis fragment analysis and clone sequencing in detecting dynamic mutations of spinocerebellar ataxia (SCA. Methods Capillary electrophoresis fragment analysis and clone sequencing were used in detecting trinucleotide repeated sequence of 14 SCA patients (3 cases of SCA2, 2 cases of SCA7, 7 cases of SCA8 and 2 cases of SCA17. Results Capillary electrophoresis fragment analysis of 3 SCA2 cases showed the expanded cytosine-adenine-guanine (CAG repeats were 31, 30 and 32, and the copy numbers of 3 clone sequencing for 3 colonies in each case were 37/40/40, 37/38/39 and 38/39/40 respectively. Capillary electrophoresis fragment analysis of 2 SCA7 cases showed the expanded CAG repeats were 57 and 34, and the copy numbers of repeats were 69, 74, 75 in 3 colonies of one case, and was 45 in the other case. For the 7 SCA8 cases with the expanded cytosine-thymine-adenine (CTA/cytosine-thymine-guanine (CTG repeats of 99, 111, 104, 92, 89, 104 and 75, the results of clone sequencing were 97, 116, 104, 90, 90, 102 and 76 respectively. For 2 SCA17 cases with the short/expanded CAG repeats of 37/50 and 36/45, the results of clone sequencing were 51/50/52 and 45/44 for 3 and 2 colonies. Conclusions Although the higher mobility of polymerase chain reaction (PCR products containing dynamic mutation in the capillary electrophoresis fragment analysis might cause the deviation for analysis of copy numbers, the deviation was predictable and the results were repeatable. The clone sequencing results showed obvious instability, especially for SCA2 and SCA7 genes, which might owing to their simple CAG repeats. Consequently, clone sequencing is not suited for detection of dynamic mutation, not to mention the quantitative criteria of dynamic mutation sequencing. DOI: 10.3969/j.issn.1672-6731.2018.03.008

  12. Presymptomatic breast cancer in Egypt: role of BRCA1 and BRCA2 tumor suppressor genes mutations detection

    Directory of Open Access Journals (Sweden)

    Hashishe Mervat M

    2010-06-01

    Full Text Available Abstract Background Breast cancer is one of the most common diseases affecting women. Inherited susceptibility genes, BRCA1 and BRCA2, are considered in breast, ovarian and other common cancers etiology. BRCA1 and BRCA2 genes have been identified that confer a high degree of breast cancer risk. Objective Our study was performed to identify germline mutations in some exons of BRCA1 and BRCA2 genes for the early detection of presymptomatic breast cancer in females. Methods This study was applied on Egyptian healthy females who first degree relatives to those, with or without a family history, infected with breast cancer. Sixty breast cancer patients, derived from 60 families, were selected for molecular genetic testing of BRCA1 and BRCA2 genes. The study also included 120 healthy first degree female relatives of the patients, either sisters and/or daughters, for early detection of presymptomatic breast cancer mutation carriers. Genomic DNA was extracted from peripheral blood lymphocytes of all the studied subjects. Universal primers were used to amplify four regions of the BRCA1 gene (exons 2,8,13 and 22 and one region (exon 9 of BRCA2 gene using specific PCR. The polymerase chain reaction was carried out. Single strand conformation polymorphism assay and heteroduplex analysis were used to screen for mutations in the studied exons. In addition, DNA sequencing of the normal and mutated exons were performed. Results Mutations in both BRCA1 and BRCA2 genes were detected in 86.7% of the families. Current study indicates that 60% of these families were attributable to BRCA1 mutations, while 26.7% of them were attributable to BRCA2 mutations. Results showed that four mutations were detected in the BRCA1 gene, while one mutation was detected in the BRCA2 gene. Asymptomatic relatives, 80(67% out of total 120, were mutation carriers. Conclusions BRCA1 and BRCA2 genes mutations are responsible for a significant proportion of breast cancer. BRCA mutations

  13. Detection of MPLW515L/K mutations and determination of allele frequencies with a single-tube PCR assay.

    Science.gov (United States)

    Takei, Hiraku; Morishita, Soji; Araki, Marito; Edahiro, Yoko; Sunami, Yoshitaka; Hironaka, Yumi; Noda, Naohiro; Sekiguchi, Yuji; Tsuneda, Satoshi; Ohsaka, Akimichi; Komatsu, Norio

    2014-01-01

    A gain-of-function mutation in the myeloproliferative leukemia virus (MPL) gene, which encodes the thrombopoietin receptor, has been identified in patients with essential thrombocythemia and primary myelofibrosis, subgroups of classic myeloproliferative neoplasms (MPNs). The presence of MPL gene mutations is a critical diagnostic criterion for these diseases. Here, we developed a rapid, simple, and cost-effective method of detecting two major MPL mutations, MPLW515L/K, in a single PCR assay; we termed this method DARMS (dual amplification refractory mutation system)-PCR. DARMS-PCR is designed to produce three different PCR products corresponding to MPLW515L, MPLW515K, and all MPL alleles. The amplicons are later detected and quantified using a capillary sequencer to determine the relative frequencies of the mutant and wild-type alleles. Applying DARMS-PCR to human specimens, we successfully identified MPL mutations in MPN patients, with the exception of patients bearing mutant allele frequencies below the detection limit (5%) of this method. The MPL mutant allele frequencies determined using DARMS-PCR correlated strongly with the values determined using deep sequencing. Thus, we demonstrated the potential of DARMS-PCR to detect MPL mutations and determine the allele frequencies in a timely and cost-effective manner.

  14. Detection of MPLW515L/K mutations and determination of allele frequencies with a single-tube PCR assay.

    Directory of Open Access Journals (Sweden)

    Hiraku Takei

    Full Text Available A gain-of-function mutation in the myeloproliferative leukemia virus (MPL gene, which encodes the thrombopoietin receptor, has been identified in patients with essential thrombocythemia and primary myelofibrosis, subgroups of classic myeloproliferative neoplasms (MPNs. The presence of MPL gene mutations is a critical diagnostic criterion for these diseases. Here, we developed a rapid, simple, and cost-effective method of detecting two major MPL mutations, MPLW515L/K, in a single PCR assay; we termed this method DARMS (dual amplification refractory mutation system-PCR. DARMS-PCR is designed to produce three different PCR products corresponding to MPLW515L, MPLW515K, and all MPL alleles. The amplicons are later detected and quantified using a capillary sequencer to determine the relative frequencies of the mutant and wild-type alleles. Applying DARMS-PCR to human specimens, we successfully identified MPL mutations in MPN patients, with the exception of patients bearing mutant allele frequencies below the detection limit (5% of this method. The MPL mutant allele frequencies determined using DARMS-PCR correlated strongly with the values determined using deep sequencing. Thus, we demonstrated the potential of DARMS-PCR to detect MPL mutations and determine the allele frequencies in a timely and cost-effective manner.

  15. An Acquired HER2T798I Gatekeeper Mutation Induces Resistance to Neratinib in a Patient with HER2 Mutant-Driven Breast Cancer.

    Science.gov (United States)

    Hanker, Ariella B; Brewer, Monica Red; Sheehan, Jonathan H; Koch, James P; Sliwoski, Gregory R; Nagy, Rebecca; Lanman, Richard; Berger, Michael F; Hyman, David M; Solit, David B; He, Jie; Miller, Vincent; Cutler, Richard E; Lalani, Alshad S; Cross, Darren; Lovly, Christine M; Meiler, Jens; Arteaga, Carlos L

    2017-06-01

    We report a HER2 T798I gatekeeper mutation in a patient with HER2 L869R -mutant breast cancer with acquired resistance to neratinib. Laboratory studies suggested that HER2 L869R is a neratinib-sensitive, gain-of-function mutation that upon dimerization with mutant HER3 E928G , also present in the breast cancer, amplifies HER2 signaling. The patient was treated with neratinib and exhibited a sustained partial response. Upon clinical progression, HER2 T798I was detected in plasma tumor cell-free DNA. Structural modeling of this acquired mutation suggested that the increased bulk of isoleucine in HER2 T798I reduces neratinib binding. Neratinib blocked HER2-mediated signaling and growth in cells expressing HER2 L869R but not HER2 L869R/T798I In contrast, afatinib and the osimertinib metabolite AZ5104 strongly suppressed HER2 L869R/T798I -induced signaling and cell growth. Acquisition of HER2 T798I upon development of resistance to neratinib in a breast cancer with an initial activating HER2 mutation suggests HER2 L869R is a driver mutation. HER2 T798I -mediated neratinib resistance may be overcome by other irreversible HER2 inhibitors like afatinib. Significance: We found an acquired HER2 gatekeeper mutation in a patient with HER2 -mutant breast cancer upon clinical progression on neratinib. We speculate that HER2 T798I may arise as a secondary mutation following response to effective HER2 tyrosine kinase inhibitors (TKI) in other cancers with HER2 -activating mutations. This resistance may be overcome by other irreversible HER2 TKIs, such as afatinib. Cancer Discov; 7(6); 575-85. ©2017 AACR. This article is highlighted in the In This Issue feature, p. 539 . ©2017 American Association for Cancer Research.

  16. Detection of the acetylcholinesterase insecticide resistance mutation (G328A) in natural populations of Ceratitis capitata

    International Nuclear Information System (INIS)

    Elfekih, Samia; Haran, Julien; Shannon, Matthew; Vogler, Alfried P.

    2015-01-01

    Wild Mediterranean fruit fly specimens collected from various regions worldwide were screened for the glycine to alanine (Gly->Ala) point mutation (G328A) in the acetylcholinesterase enzyme, presumably causing resistance to organophosphates. We found that the single nucleotide polymorphism (SNP) responsible for this amino acid change is located at the beginning of exon 6 of the Ccace2 gene. The identification of the exact location of the SNP permitted PCR primer design around this site and direct sequencing of the corresponding genomic region. We detected the resistance allele in natural Mediterranean fruit fly populations from Brazil and Spain, but not from other sites in four continents. The known treatment history of sites suggests that the resistance build up is linked to organophosphate application in the held. The PCR-based detection provides a screening method useful for monitoring Mediterranean fruit fly insecticide resistance in local populations and improving pest management strategies accordingly. (author)

  17. Germ-line PHD1 and PHD2 mutations detected in patients with pheochromocytoma/paraganglioma-polycythemia.

    Science.gov (United States)

    Yang, Chunzhang; Zhuang, Zhengping; Fliedner, Stephanie M J; Shankavaram, Uma; Sun, Michael G; Bullova, Petra; Zhu, Roland; Elkahloun, Abdel G; Kourlas, Peter J; Merino, Maria; Kebebew, Electron; Pacak, Karel

    2015-01-01

    We have investigated genetic/pathogenetic factors associated with a new clinical entity in patients presenting with pheochromocytoma/paraganglioma (PHEO/PGL) and polycythemia. Two patients without hypoxia-inducible factor 2α (HIF2A) mutations, who presented with similar clinical manifestations, were analyzed for other gene mutations, including prolyl hydroxylase (PHD) mutations. We have found for the first time a germ-line mutation in PHD1 in one patient and a novel germ-line PHD2 mutation in a second patient. Both mutants exhibited reduced protein stability with substantial quantitative protein loss and thus compromised catalytic activities. Due to the unique association of patients' polycythemia with borderline or mildly elevated erythropoietin (EPO) levels, we also performed an in vitro sensitivity assay of erythroid progenitors to EPO and for EPO receptor (EPOR) expression. The results show inappropriate hypersensitivity of erythroid progenitors to EPO in these patients, indicating increased EPOR expression/activity. In addition, the present study indicates that HIF dysregulation due to PHD mutations plays an important role in the pathogenesis of these tumors and associated polycythemia. The PHD1 mutation appears to be a new member contributing to the genetic landscape of this novel clinical entity. Our results support the existence of a specific PHD1- and PHD2-associated PHEO/PGL-polycythemia disorder. • A novel germ-l i n e PHD1 mutation causing heochromocytoma/paraganglioma and polycythemia. • Increased EPOR activity and inappropriate hypersensitivity of erythroid progenitors to EPO.

  18. Dissolved oxygen detection by galvanic displacement-induced

    Indian Academy of Sciences (India)

    Dissolved oxygen detection by galvanic displacement-induced graphene/silver nanocomposite ... dissolved oxygen (DO) detection based on a galvanic displacement synthesized reduced graphene oxide–silver nanoparticles ... Current Issue

  19. In utero exposure to nanosized carbon black (Printex90) does not induce tandem repeat mutations in female murine germ cells

    DEFF Research Database (Denmark)

    Boisen, Anne Mette Zenner; Shipley, Thomas; Jackson, Petra

    2013-01-01

    Inhalation of particles has been shown to induce mutations in the male germline in mice following both prenatal and adult exposures in several experiments. In contrast, the effects of particles on female germ cell mutagenesis are not well established. Germline mutations are induced during active...... cell division, which occurs during fetal development in females. We investigated the effects of prenatal exposure to carbon black nanoparticles (CB) on induction of mutations in the female mouse germline during fetal development, spanning the critical developmental stages of oogenesis. Pregnant C57BL/6...... mutation rates in the resulting F2 generation were determined from full pedigrees (mother, father, offspring) of F1 female mice (178 CB-exposed and 258 control F2 offspring). ESTR mutation rates in CB-exposed F2 female offspring were not statistically different from those of F2 female control offspring....

  20. Molecular cytogenetics of radiation-induced gene mutations in Drosophila melanogaster

    International Nuclear Information System (INIS)

    Aleksandrov, I.D.; Aleksandrova, M.V.; Lapidus, I.L.; Karpovskij, A.L.

    1996-01-01

    The classical paradigm of spatially unrelated lesions for gene mutations and chromosomal exchange breakpoints induced by ionizing radiations in eukaryotic cells was re-examined in the experiments on the mapping of gamma-ray- or neutron-induced breakpoints in and outside of white (w) and vestigial (vg) genes of Drosophila melanogaster using the in situ hybridization of the large fragments of the genes under study with the polythene chromosomes of the relevant mutants. The results for the random sample of 60 inversion and translocation breakpoints analysed to date have shown that (i) 50% of them are mapped as the hot spots within big introns of both the genes, and (ii) 21 of 60 breaks (35%) are located outside of genes. It is important to note that 26% (16/60) of the breakpoints analysed are flanked by the deletions, the sizes of which vary from the quarter to a whole of the gene. It was found that the deletions flank both the inversion and translocation breakpoints and arise more often after action of neutrons than photons. An unexpectedly high frequency of the multiple-damaged w and vg mutants that have the gene/point mutation and additional, but separate, chromosome exchange (the so-called double- or triple-site mutants) has shown that the genetic danger of ionizing radiation is higher than usually accepted on the base of single gene/point mutation assessments. 11 refs., 3 figs

  1. Stability Test For Sorghum Mutant Lines Derived From Induced Mutations with Gamma-Ray Irradiation

    Directory of Open Access Journals (Sweden)

    S. Human

    2011-12-01

    Full Text Available Sorghum breeding program had been conducted at the Center for the Application of Isotopes and Radiation Technology, BATAN. Plant genetic variability was increased through induced mutations using gamma-ray irradiation. Through selection process in successive generations, some promising mutant lines had been identified to have good agronomic characteristics with high grain yield. These breeding lines were tested in multi location trials and information of the genotypic stability was obtained to meet the requirements for officially varietal release by the Ministry of Agriculture. A total of 11 sorghum lines and varieties consisting of 8 mutant lines derived from induced mutations (B-100, B-95, B-92, B-83, B-76, B-75, B-69 and Zh-30 and 3 control varieties (Durra, UPCA-S1 and Mandau were included in the experiment. All materials were grown in 10 agro-ecologically different locations namely Gunungkidul, Bantul, Citayam, Garut, Lampung, Bogor, Anyer, Karawaci, Cianjur and Subang. In each location, the local adaptability test was conducted by randomized block design with 3 replications. Data of grain yield was used for evaluating genotypic stability using AMMI approach. Results revealed that sorghum mutation breeding had generated 3 mutant lines (B-100, B-76 and Zh-30 exhibiting grain yield significantly higher than the control varieties. These mutant lines were genetically stable in all locations so that they would be recommended for official release as new sorghum varieties to the Ministry of Agriculture

  2. Identifying EGFR-Expressed Cells and Detecting EGFR Multi-Mutations at Single-Cell Level by Microfluidic Chip

    Science.gov (United States)

    Li, Ren; Zhou, Mingxing; Li, Jine; Wang, Zihua; Zhang, Weikai; Yue, Chunyan; Ma, Yan; Peng, Hailin; Wei, Zewen; Hu, Zhiyuan

    2018-03-01

    EGFR mutations companion diagnostics have been proved to be crucial for the efficacy of tyrosine kinase inhibitor targeted cancer therapies. To uncover multiple mutations occurred in minority of EGFR-mutated cells, which may be covered by the noises from majority of un-mutated cells, is currently becoming an urgent clinical requirement. Here we present the validation of a microfluidic-chip-based method for detecting EGFR multi-mutations at single-cell level. By trapping and immunofluorescently imaging single cells in specifically designed silicon microwells, the EGFR-expressed cells were easily identified. By in situ lysing single cells, the cell lysates of EGFR-expressed cells were retrieved without cross-contamination. Benefited from excluding the noise from cells without EGFR expression, the simple and cost-effective Sanger's sequencing, but not the expensive deep sequencing of the whole cell population, was used to discover multi-mutations. We verified the new method with precisely discovering three most important EGFR drug-related mutations from a sample in which EGFR-mutated cells only account for a small percentage of whole cell population. The microfluidic chip is capable of discovering not only the existence of specific EGFR multi-mutations, but also other valuable single-cell-level information: on which specific cells the mutations occurred, or whether different mutations coexist on the same cells. This microfluidic chip constitutes a promising method to promote simple and cost-effective Sanger's sequencing to be a routine test before performing targeted cancer therapy.[Figure not available: see fulltext.

  3. Modified Proofreading PCR for Detection of Point Mutations, Insertions and Deletions Using a ddNTP-Blocked Primer

    Science.gov (United States)

    Chen, Qianqian; Chen, Xiaoxiang; Zhang, Sichao; Lan, Ke; Lu, Jian; Zhang, Chiyu

    2015-01-01

    The development of simple, accurate, rapid and cost-effective technologies for mutation detection is crucial to the early diagnosis and prevention of numerous genetic diseases, pharmacogenetics, and drug resistance. Proofreading PCR (PR-PCR) was developed for mutation detection in 1998 but is rarely applied due to its low efficiency in allele discrimination. Here we developed a modified PR-PCR method using a ddNTP-blocked primer and a mixture of DNA polymerases with and without the 3'-5' proofreading function. The ddNTP-blocked primer exhibited the best blocking efficiency to avoid nonspecific primer extension while the mixture of a tiny amount of high-fidelity DNA polymerase with a routine amount of Taq DNA polymerase provided the best discrimination and amplification effects. The modified PR-PCR method is quite capable of detecting various mutation types, including point mutations and insertions/deletions (indels), and allows discrimination amplification when the mismatch is located within the last eight nucleotides from the 3'-end of the ddNTP-blocked primer. The modified PR-PCR has a sensitivity of 1-5 × 102 copies and a selectivity of 5 × 10-5 mutant among 107 copies of wild-type DNA. It showed a 100% accuracy rate in the detection of P72R germ-line mutation in the TP53 gene among 60 clinical blood samples, and a high potential to detect rifampin-resistant mutations at low frequency in Mycobacterium tuberculosis using an adaptor and a fusion-blocked primer. These results suggest that the modified PR-PCR technique is effective in detection of various mutations or polymorphisms as a simple, sensitive and promising approach. PMID:25915410

  4. Detection of CALR and MPL Mutations in Low Allelic Burden JAK2 V617F Essential Thrombocythemia.

    Science.gov (United States)

    Usseglio, Fabrice; Beaufils, Nathalie; Calleja, Anne; Raynaud, Sophie; Gabert, Jean

    2017-01-01

    Myeloproliferative neoplasms are clonal hematopoietic stem cell disorders characterized by aberrant proliferation and an increased tendency toward leukemic transformation. The genes JAK2, MPL, and CALR are frequently altered in these syndromes, and their mutations are often a strong argument for diagnosis. We analyzed the mutational profiles of these three genes in a cohort of 164 suspected myeloproliferative neoplasms. JAK2 V617F mutation was detected by real-time PCR, whereas high-resolution melting analysis followed by Sanger sequencing were used for searching for mutations in JAK2 exon 12, CALR, and MPL. JAK2 V617F mutation was associated with CALR (n = 4) and MPL (n = 4) mutations in 8 of 103 essential thrombocytosis patients. These cases were harboring a JAK2 V617F allelic burden of MPL genes in myeloproliferative neoplasms and suggest that CALR and MPL should be analyzed not only in JAK2-negative patients but also in low V617F mutation patients. Follow-up of these double-mutation cases will be important for determining whether this group of patients presents particular evolution or complications. Copyright © 2017 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

  5. A Locked Nucleic Acid Probe Based on Selective Salt-Induced Effect Detects Single Nucleotide Polymorphisms

    Directory of Open Access Journals (Sweden)

    Jing Zhang

    2015-01-01

    Full Text Available Detection of single based genetic mutation by using oligonucleotide probes is one of the common methods of detecting single nucleotide polymorphisms at known loci. In this paper, we demonstrated a hybridization system which included a buffer solution that produced selective salt-induced effect and a locked nucleic acid modified 12 nt oligonucleotide probe. The hybridization system is suitable for hybridization under room temperature. By using magnetic nanoparticles as carriers for PCR products, the SNPs (MDR1 C3435T/A from 45 volunteers were analyzed, and the results were consistent with the results from pyrophosphoric acid sequencing. The method presented in this paper differs from the traditional method of using molecular beacons to detect SNPs in that it is suitable for research institutions lacking real-time quantitative PCR detecting systems, to detect PCR products at room temperature.

  6. Utilization of induced mutation techniques in rice improvement in the Philippines

    International Nuclear Information System (INIS)

    Asencion, A.B.; Santos, I.S.; Barrida, A.C.; Medina, F.I.S. III

    2001-01-01

    Rice is one of the most important food crops in the Philippines, as such, efforts have been made consistently to improve the varieties released to the farmers for planting. Both conventional and induced mutation techniques were utilized to solve some of the problems. Varieties with improved qualities, resistance to pests and diseases, reduced height, early maturity and non-photoperiod sensitive were developed using either physical or chemical mutagen. Other methods were also tried to enhance variability like combination of gamma irradiation and biotechnology. Irradiation of F1 seeds was also initiated including the use of mutants in crosses to transfer their improved mutated characters. Promising selections were already tested and six lines from the F1 irradiation out-yielded both C4-63G and IR 1561-288-3, their parents. (author)

  7. Was Muller's 1946 Nobel Prize research for radiation-induced gene mutations peer-reviewed?

    Science.gov (United States)

    Calabrese, Edward J

    2018-06-06

    This historical analysis indicates that it is highly unlikely that the Nobel Prize winning research of Hermann J. Muller was peer-reviewed. The published paper of Muller lacked a research methods section, cited no references, and failed to acknowledge and discuss the work of Gager and Blakeslee (PNAS 13:75-79, 1927) that claimed to have induced gene mutation via ionizing radiation six months prior to Muller's non-data Science paper (Muller, Science 66(1699):84-87, 1927a). Despite being well acclimated into the scientific world of peer-review, Muller choose to avoid the peer-review process on his most significant publication. It appears that Muller's actions were strongly influenced by his desire to claim primacy for the discovery of gene mutation. The actions of Muller have important ethical lessons and implications today, when self-interest trumps one's obligations to society and the scientific culture that supports the quest for new knowledge and discovery.

  8. Induced mutation aiming at obtaining lodging resistance in wheat C V.Omid(Triticum Aestivum)

    International Nuclear Information System (INIS)

    Majd, F.; Rezazadeh, M.; Ghohari, A.

    1993-01-01

    Mutation breeding has been an important part breeding research for solving some of the existing problems related to wheat. A locally adopted wheat cultivar 'Omid' which is a traditionally tall wheat mostly cultivated in regions with a continental climate and is susceptible to lodging was chosen as research material. The nuclear research department for agriculture of Atomic Energy Organization of Iran initiated a mutation breeding program for creating genetic variability in wheat using this local cultivar. Seeds of this variety was irradiated with gamma radiation (50-150 Gy) to induce short straw mutants with greater lodging resistance and yield potential. from a total of about 20000 irradiated seeds 1500 plants showing promising agronomic character were isolated as potential mutants. Following progeny tests and selection 18 mutants lines entered preliminary yield trail. Further field trails at different locations gave two promising lines which are characterized by higher yield, lodging resistance and early maturity. (author). 3 tabs

  9. Utilization of induced mutation techniques in rice improvement in the Philippines

    Energy Technology Data Exchange (ETDEWEB)

    Asencion, A.B.; Santos, I.S.; Barrida, A.C.; Medina, F.I.S. III [Philippine Nuclear Research Institute, Atomic Research Center (Philippines)

    2001-03-01

    Rice is one of the most important food crops in the Philippines, as such, efforts have been made consistently to improve the varieties released to the farmers for planting. Both conventional and induced mutation techniques were utilized to solve some of the problems. Varieties with improved qualities, resistance to pests and diseases, reduced height, early maturity and non-photoperiod sensitive were developed using either physical or chemical mutagen. Other methods were also tried to enhance variability like combination of gamma irradiation and biotechnology. Irradiation of F1 seeds was also initiated including the use of mutants in crosses to transfer their improved mutated characters. Promising selections were already tested and six lines from the F1 irradiation out-yielded both C4-63G and IR 1561-288-3, their parents. (author)

  10. Induced mutation and in vitro culture techniques for the genetic improvement of ornamentals

    International Nuclear Information System (INIS)

    Lapade, Avelina G.; Veluz, Ana Maria S.; Marbella, Lucia J.; Rama, Manny G.

    2001-01-01

    Mutation breeding using cobalt-60 ( 60 Co) gamma radiation coupled with tissue culture techniques is undertaken for genetic improvement of foliage ornamentals (Dracaena sp. and Murraya exotica L.) and cutflowers (Chrysanthemum morifolium and orchids; Vanda sanderiana, Dendrobium Pattaya Beauty and Phalenopsis schilleriana). Gamma radiation (10-30 Gy) induced chlorophyll mutations and several morphological changes in D. sanderiana. For D. godseffiana, irradiated cuttings resulted in reduction of leaf size and chlorophyll mutations. Reduction in height was observed in the M 2 generation of Murraya exotica L. irradiated at doses ranging from 10 to 30 Gy. The dwarf Murraya mutant was multiplied through the use of seeds and presently 116 plants are commercially available and are ''test marketed'' to the public. Tissue culture technique was used to induce mutation and as a means of micropropagation in two ornamental crops (orchids and chrysanthemum). Effects of different doses of gamma radiation on callus induction from nodal sections of chrysanthemum grown in Murashige and Skoog's (MS) with naphthalene acetic acid (NAA) and benzyl adenine (BA) were studied. Micropropagation of irradiated and unirradiated chrysanthemum using MS basal medium is presently being studied. Whorling and changes in leaf color were observed at 10 Gy and doubling of leaf growth at the node at 20 Gy for vegetatively generated V 3 plant. In orchids, irradiation of immature embryo with gamma rays ranging from 5 to 10 Gy increased the percentage of germination in Dendrobium Pattaya Beauty and P. schilleriana. Protocorms of Vanda sanderiana irradiated at 10 Gy and grown in Knudson C medium developed into plantlets that are bigger and more vigorous than those irradiated at 20 GY and from the control plant. A decrease in seedling height was observed with increasing dose of gamma radiation. (Author)

  11. Development of radiation-induced mutation techniques and functional genomics studies

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong Sub; Kang, Si Yong; Kim, Jin Baek [KAERI, Daejeon (Korea, Republic of); and others

    2012-01-15

    This project has been performed to develop plant genetic resources using radiation (gamma-rays, ion-beam, space environments), to conduct functional genomics studies with mutant resources, and to develop new radiation plant breeding techniques using various radiation sources during 3 years. In the first section, we developed flower genetic resources, functional crop resources, and bio-industrial plant resources. In the second section, we cloned several mutated genes and studied mechanisms of gene expression and genetic diversity of mutations induced by gamma-rays. In the third section, we developed new plant breeding techniques using gamma-phytotron, heavy ion-beam, and space environments. Based on these results, a total of 8 cultivars containing Chrysanthemum, Hibiscus, kenaf, rice, and soybean were applied for plant variety protection (PVP) and a total of 4 cultivars were registered for PVP. Also, license agreement for the dwarf type Hibiscus mutant 'Ggoma' was conducted with Supro co. and the manufacturing technology for natural antioxidant pear-grape vinegar was transferred into Enzenic co. Also, 8 gene sequences, such as F3'H and LDOX genes associated with flower color in Chrysanthemum and EPSPS gene from Korean lawn grass, were registered in the database of National Center for Biotechnology Information (NCBI). In the future study, we will develop new radiation mutation breeding techniques through the mutation spectrum induced by various radiation sources, the studies for mechanism of the cellular response to radiation, and the comparative{center_dot}structural{center_dot}functional genomics studies for useful traits.

  12. Direct detection of hemophilia B F9 gene mutation using multiplex PCR and conformation sensitive gel electrophoresis

    Directory of Open Access Journals (Sweden)

    Ki Young Yoo

    2010-03-01

    Full Text Available Purpose : The F9 gene is known to be the causative gene for hemophilia B, but unfortunately the detection rate for restriction fragment length polymorphism-based linkage analysis is only 55.6%. Direct DNA sequencing can detect 98% of mutations, but this alternative procedure is very costly. Here, we conducted multiplex polymerase chain reactions (PCRs and conformation sensitive gel electrophoresis (CSGE to perform a screened DNA sequencing for the F9 gene, and we compared the results with direct sequencing in terms of accuracy, cost, simplicity, and time consumption. Methods : A total of 27 unrelated hemophilia B patients were enrolled. Direct DNA sequencing was performed for 27 patients by a separate institute, and multiplex PCR-CSGE screened sequencing was done in our laboratory. Results of the direct DNA sequencing were used as a reference, to which the results of the multiplex PCR-CSGE screened sequencing were compared. For the patients whose mutation was not detected by the 2 methods, multiplex ligation-dependent probe amplification (MLPA was conducted. Results : With direct sequencing, the mutations could be identified from 26 patients (96.3%, whereas for multiplex PCR- CSGE screened sequencing, the mutations could be detected in 23 (85.2%. One patient’s mutation was identified by MLPA. A total of 21 different mutations were found among the 27 patients. Conclusion : Multiplex PCR-CSGE screened DNA sequencing detected 88.9% of mutations and reduced costs by 55.7% compared with direct DNA sequencing. However, it was more labor-intensive and time-consuming.

  13. HorTILLUS—A Rich and Renewable Source of Induced Mutations for Forward/Reverse Genetics and Pre-breeding Programs in Barley (Hordeum vulgare L.

    Directory of Open Access Journals (Sweden)

    Miriam E. Szurman-Zubrzycka

    2018-02-01

    Full Text Available TILLING (Targeting Induced Local Lesions IN Genomes is a strategy used for functional analysis of genes that combines the classical mutagenesis and a rapid, high-throughput identification of mutations within a gene of interest. TILLING has been initially developed as a discovery platform for functional genomics, but soon it has become a valuable tool in development of desired alleles for crop breeding, alternative to transgenic approach. Here we present the HorTILLUS (Hordeum—TILLING—University of Silesia population created for spring barley cultivar “Sebastian” after double-treatment of seeds with two chemical mutagens: sodium azide (NaN3 and N-methyl-N-nitrosourea (MNU. The population comprises more than 9,600 M2 plants from which DNA was isolated, seeds harvested, vacuum-packed, and deposited in seed bank. M3 progeny of 3,481 M2 individuals was grown in the field and phenotyped. The screening for mutations was performed for 32 genes related to different aspects of plant growth and development. For each gene fragment, 3,072–6,912 M2 plants were used for mutation identification using LI-COR sequencer. In total, 382 mutations were found in 182.2 Mb screened. The average mutation density in the HorTILLUS, estimated as 1 mutation per 477 kb, is among the highest mutation densities reported for barley. The majority of mutations were G/C to A/T transitions, however about 8% transversions were also detected. Sixty-one percent of mutations found in coding regions were missense, 37.5% silent and 1.1% nonsense. In each gene, the missense mutations with a potential effect on protein function were identified. The HorTILLUS platform is the largest of the TILLING populations reported for barley and best characterized. The population proved to be a useful tool, both in functional genomic studies and in forward selection of barley mutants with required phenotypic changes. We are constantly renewing the HorTILLUS population, which makes it a

  14. Real-time PCR-based method for the rapid detection of extended RAS mutations using bridged nucleic acids in colorectal cancer.

    Science.gov (United States)

    Iida, Takao; Mizuno, Yukie; Kaizaki, Yasuharu

    2017-10-27

    Mutations in RAS and BRAF are predictors of the efficacy of anti-epidermal growth factor receptor (EGFR) therapy in patients with metastatic colorectal cancer (mCRC). Therefore, simple, rapid, cost-effective methods to detect these mutations in the clinical setting are greatly needed. In the present study, we evaluated BNA Real-time PCR Mutation Detection Kit Extended RAS (BNA Real-time PCR), a real-time PCR method that uses bridged nucleic acid clamping technology to rapidly detect mutations in RAS exons 2-4 and BRAF exon 15. Genomic DNA was extracted from 54 formalin-fixed paraffin-embedded (FFPE) tissue samples obtained from mCRC patients. Among the 54 FFPE samples, BNA Real-time PCR detected 21 RAS mutations (38.9%) and 5 BRAF mutations (9.3%), and the reference assay (KRAS Mutation Detection Kit and MEBGEN™ RASKET KIT) detected 22 RAS mutations (40.7%). The concordance rate of detected RAS mutations between the BNA Real-time PCR assay and the reference assays was 98.2% (53/54). The BNA Real-time PCR assay proved to be a more simple, rapid, and cost-effective method for detecting KRAS and RAS mutations compared with existing assays. These findings suggest that BNA Real-time PCR is a valuable tool for predicting the efficacy of early anti-EGFR therapy in mCRC patients. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Rasfonin, a novel 2-pyrone derivative, induces ras-mutated Panc-1 pancreatic tumor cell death in nude mice.

    Science.gov (United States)

    Xiao, Z; Li, L; Li, Y; Zhou, W; Cheng, J; Liu, F; Zheng, P; Zhang, Y; Che, Y

    2014-05-22

    Rasfonin is a novel 2-pyrone derivative reported to induce apoptosis in ras-dependent cells. In this study, its effects on ras-mutated pancreatic cancer cells were investigated in vitro and in vivo. Two human pancreatic cancer cell lines Panc-1 (mutated K-ras) and BxPC-3 (wild-type K-ras) were selected to test the effects of rasfonin on cell proliferation, clone formation, migration and invasion in vitro. Immunoblotting was used to detect the expressions of EGFR-Ras-Raf-MEK-ERK signaling pathway proteins. Ras activity was measured using a pull-down ELISA kit and guanine exchange factor (GEF)/GTPase-activating proteins (GAP) activity was measured by [(3)H]-GDP radiometric ligand binding. For an in vivo study, CD1 nude mice bearing Panc-1 cells were treated with rasfonin or Salirasib (FTS). We found that rasfonin suppressed proliferation more strongly in Panc-1 cells (IC50=5.5 μM) than BxPC-3 cells (IC50=10 μM) in vitro. Clone formation, migration and invasion by Panc-1 cells were also reduced by rasfonin. Rasfonin had little effect on the farnesylation of Ras, but it strongly downregulated Ras activity and consequently phosphorylation of c-Raf/MEK/ERK. Further experiments indicated that rasfonin reduced Son of sevenless (Sos1) expression but did not alter GEF and GAP activities. The in vivo experiments also revealed that rasfonin (30 mg/kg) delayed the growth of xenograft tumors originating from Panc-1 cells. Tumor weight was ultimately decreased after 20 days of treatment of rasfonin. Rasfonin is a robust inhibitor of pancreatic cancers with the K-ras mutation. The reduction of Sos1 expression and the consequently depressed Ras-MAPK activity could be important in its anticancer activity.

  16. Present status of rice breeding by induced mutations in Taiwan, Republic of China

    Energy Technology Data Exchange (ETDEWEB)

    Hu, C H [Taiwan Provincial Chung-Hsing University, Taichung, Taiwan (China); Wu, H P; Li, H W [Academia Sinica, Nankang, Taipei, Taiwan (China)

    1970-03-01

    Since 1957, fourteen varieties, including both indica and japonica, have been treated with X-rays, gamma rays, thermal neutrons and EMS for inducing mutations. The objectives are: (1) To obtain erectoid mutants of good lodging resistance from the tall native varieties which can be adapted for intensive culture; (2) To obtain early maturing mutants with at least the same yield as the original variety, so that the multiple cropping system of Taiwan can be easily handled; and (3) To obtain disease-resistant mutants. The results obtained suggest that after a useful gene such as erectoid has been obtained by induced mutation, it can be used immediately. But in general, it will be more useful to combine this character into other genotypic backgrounds by cross-breeding. Henceforth, further breeding must be carried out by cross-breeding. A number of promising lines were selected from induced mutants after being crossed with local varieties and the advanced test of these lines is being carried on at present. (author)

  17. Present status of rice breeding by induced mutations in Taiwan, Republic of China

    International Nuclear Information System (INIS)

    Hu, C.H.; Wu, H.P.; Li, H.W.

    1970-01-01

    Since 1957, fourteen varieties, including both indica and japonica, have been treated with X-rays, gamma rays, thermal neutrons and EMS for inducing mutations. The objectives are: (1) To obtain erectoid mutants of good lodging resistance from the tall native varieties which can be adapted for intensive culture; (2) To obtain early maturing mutants with at least the same yield as the original variety, so that the multiple cropping system of Taiwan can be easily handled; and (3) To obtain disease-resistant mutants. The results obtained suggest that after a useful gene such as erectoid has been obtained by induced mutation, it can be used immediately. But in general, it will be more useful to combine this character into other genotypic backgrounds by cross-breeding. Henceforth, further breeding must be carried out by cross-breeding. A number of promising lines were selected from induced mutants after being crossed with local varieties and the advanced test of these lines is being carried on at present. (author)

  18. Genetic and molecular analyses of UV radiation-induced mutations in the fem-3 gene of Caenorhabditis elegans

    Energy Technology Data Exchange (ETDEWEB)

    Hartman, P S; De Wilde, D; Dwarakanath, V N [Texas Christian Univ., Fort Worth, TX (United States). Dept. of Biology

    1995-06-01

    The utility of a new target gene (fem-3) is described for investigating the molecular nature of mutagenesis in the nematode Caenorhabditis elegans. As a principal attribute, this system allows for the selection, maintenance and molecular analysis of any type of mutation that disrupts the gene, including deletions. In this study, 86 mutant strains were isolated, of which 79 proved to have mutations in fem-3. Twenty of these originally tested as homozygous inviable. Homozygous inviability was expected, as Stewart and coworkers had previously observed that, unlike in other organisms, most UV radiation-induced mutations in C. elegans are chromosomal rearrangements of deficiencies (Mutat. Res 249, 37-54, 1991). However, additional data, including Southern blot analyses on 49 of the strains, indicated that most of the UV radiation-induced fem-3 mutations were not deficiencies, as originally inferred from their homozygous inviability. Instead, the lethals were most likely ``coincident mutations`` in linked, essential genes that were concomitantly induced. As such, they were lost owing to genetic recombination during stock maintenance. As in mammalian cells, yeast and bacteria, the frequency of coincident mutations was much higher than would be predicted by chance. (Author).

  19. Non-homologous end joining dependency of {gamma}-irradiation-induced adaptive frameshift mutation formation in cell cycle-arrested yeast cells

    Energy Technology Data Exchange (ETDEWEB)

    Heidenreich, Erich [Institute of Cancer Research, Division of Molecular Genetics, Medical University of Vienna, Borschkegasse 8a, A-1090 Vienna (Austria)]. E-mail: erich.heidenreich@meduniwien.ac.at; Eisler, Herfried [Institute of Cancer Research, Division of Molecular Genetics, Medical University of Vienna, Borschkegasse 8a, A-1090 Vienna (Austria)

    2004-11-22

    There is a strong selective pressure favoring adaptive mutations which relieve proliferation-limiting adverse living conditions. Due to their importance for evolution and pathogenesis, we are interested in the mechanisms responsible for the formation of such adaptive, gain-of-fitness mutations in stationary-phase cells. During previous studies on the occurrence of spontaneous reversions of an auxotrophy-causing frameshift allele in the yeast Saccharomyces cerevisiae, we noticed that about 50% of the adaptive reversions depended on a functional non-homologous end joining (NHEJ) pathway of DNA double-strand break (DSB) repair. Here, we show that the occasional NHEJ component Pol4, which is the yeast ortholog of mammalian DNA polymerase lambda, is not required for adaptive mutagenesis. An artificially imposed excess of DSBs by {gamma}-irradiation resulted in a dramatic increase in the incidence of adaptive, cell cycle arrest-releasing frameshift reversions. By the use of DNA ligase IV-deficient strains we detected that the majority of the {gamma}-induced adaptive mutations were also dependent on a functional NHEJ pathway. This suggests that the same mutagenic NHEJ mechanism acts on spontaneously arising as well as on ionizing radiation-induced DSBs. Inaccuracy of the NHEJ repair pathway may extensively contribute to the incidence of frameshift mutations in resting (non-dividing) eukaryotic cells, and thus act as a driving force in tumor development.

  20. Non-homologous end joining dependency of γ-irradiation-induced adaptive frameshift mutation formation in cell cycle-arrested yeast cells

    International Nuclear Information System (INIS)

    Heidenreich, Erich; Eisler, Herfried

    2004-01-01

    There is a strong selective pressure favoring adaptive mutations which relieve proliferation-limiting adverse living conditions. Due to their importance for evolution and pathogenesis, we are interested in the mechanisms responsible for the formation of such adaptive, gain-of-fitness mutations in stationary-phase cells. During previous studies on the occurrence of spontaneous reversions of an auxotrophy-causing frameshift allele in the yeast Saccharomyces cerevisiae, we noticed that about 50% of the adaptive reversions depended on a functional non-homologous end joining (NHEJ) pathway of DNA double-strand break (DSB) repair. Here, we show that the occasional NHEJ component Pol4, which is the yeast ortholog of mammalian DNA polymerase lambda, is not required for adaptive mutagenesis. An artificially imposed excess of DSBs by γ-irradiation resulted in a dramatic increase in the incidence of adaptive, cell cycle arrest-releasing frameshift reversions. By the use of DNA ligase IV-deficient strains we detected that the majority of the γ-induced adaptive mutations were also dependent on a functional NHEJ pathway. This suggests that the same mutagenic NHEJ mechanism acts on spontaneously arising as well as on ionizing radiation-induced DSBs. Inaccuracy of the NHEJ repair pathway may extensively contribute to the incidence of frameshift mutations in resting (non-dividing) eukaryotic cells, and thus act as a driving force in tumor development

  1. Improvement of pulse crops through induced mutations: Reconstruction of plant type

    International Nuclear Information System (INIS)

    Rao, C.H.; Tickoo, J.L.; Ram, H.; Jain, H.K.

    1975-01-01

    Many species of grain legumes, because of their cultivation under marginal conditions for centuries, have retained a number of semi-wild characteristics, such as a bushy and spreading growth, which contribute to their adaptability but reduce their yields. The observations presented here indicate that induced mutations may prove effective in generating new plant-types in these crops, which are marked by an improvement in the harvest index and which will show a response to increased plant densities. The present report describes observations on the M 2 progenies of pigeon pea and mung bean on which work has been initiated. (author)

  2. Main biological characters of series of mutant waxy rices developed from irradiation-induced mutation

    International Nuclear Information System (INIS)

    Huang Ronghua; Zhang Shubiao; Zhang Qingqi; Yang Rencui; Lin Jinhu

    2008-01-01

    The main biological characters of the waxy male sterile lines, maintainer lines, restorer lines and waxy hybrids which had been developed by radiation-induced mutation were studied, and the grain quality of the waxy hybrids were analyzed as well. Sesults indicated that the mutant waxy rice had the same growth duration, similar agronomic characters, panicle and spikelet traits as parent. The waxy male-sterile line had the same pollen sterility characteristic as its parent male-sterile line. The waxy hybrid rice retained the yield potential as original hybrid rice, and the grain quality of the waxy hybrids was similar to the conventional waxy rice Ejinnuo 6. (authors)

  3. Chemical cleavage reactions of DNA on solid support: application in mutation detection

    Directory of Open Access Journals (Sweden)

    Cotton Richard GH

    2003-05-01

    Full Text Available Abstract Background The conventional solution-phase Chemical Cleavage of Mismatch (CCM method is time-consuming, as the protocol requires purification of DNA after each reaction step. This paper describes a new version of CCM to overcome this problem by immobilizing DNA on silica solid supports. Results DNA test samples were loaded on to silica beads and the DNA bound to the solid supports underwent chemical modification reactions with KMnO4 (potassium permanganate and hydroxylamine in 3M TEAC (tetraethylammonium chloride solution. The resulting modified DNA was then simultaneously cleaved by piperidine and removed from the solid supports to afford DNA fragments without the requirement of DNA purification between reaction steps. Conclusions The new solid-phase version of CCM is a fast, cost-effective and sensitive method for detection of mismatches and mutations.

  4. Molecular nature of X-ray-induced mutations compared with that of spontaneous ones in human c-hprt gene integrated into mammalian chromosomal DNA

    International Nuclear Information System (INIS)

    Kimura, Hiroshi; Kato, Takesi.

    1992-01-01

    X-ray-induced mutations were analysed at molecular levels in comparison with spontaneous mutations. Altered sequences were determined tentatively of 30 independent X-ray-induced mutations in a cDNA of the human hprt gene which was integrated into mammalian chromosome as a part of a shuttle vector. Mutations consisted of base substitutions (37 %), frameshifts (27 %), deletions (27 %) and others (10 %). All these mutational events were distributed randomly over the gene without there being hot spots. The spectrum and distribution of X-ray-induced mutations resembled those of spontaneous mutations. Among base substitutions, transversions were predominant and base substitution mutations occurred more at A:T sites than at G:C sites, which is also the case in spontaneous mutations. Most of the frameshift and deletion mutations induced by X-rays, as well as those spontaneously arising, were characterized by the existence of short direct repeats of several identical bases in a row at the sites of the mutations. A slippage misalignment mechanism in replication well accounts for the generation of these classes of mutations. Judging from the data accumulated so far, it can be concluded that X-ray-induced mutations at molecular levels are similar to those spontaneously occurring. (author)

  5. Rapid identification and recovery of ENU-induced mutations with next-generation sequencing and Paired-End Low-Error analysis.

    Science.gov (United States)

    Pan, Luyuan; Shah, Arish N; Phelps, Ian G; Doherty, Dan; Johnson, Eric A; Moens, Cecilia B

    2015-02-14

    Targeting Induced Local Lesions IN Genomes (TILLING) is a reverse genetics approach to directly identify point mutations in specific genes of interest in genomic DNA from a large chemically mutagenized population. Classical TILLING processes, based on enzymatic detection of mutations in heteroduplex PCR amplicons, are slow and labor intensive. Here we describe a new TILLING strategy in zebrafish using direct next generation sequencing (NGS) of 250 bp amplicons followed by Paired-End Low-Error (PELE) sequence analysis. By pooling a genomic DNA library made from over 9,000 N-ethyl-N-nitrosourea (ENU) mutagenized F1 fish into 32 equal pools of 288 fish, each with a unique Illumina barcode, we reduce the complexity of the template to a level at which we can detect mutations that occur in a single heterozygous fish in the entire library. MiSeq sequencing generates 250 base-pair overlapping paired-end reads, and PELE analysis aligns the overlapping sequences to each other and filters out any imperfect matches, thereby eliminating variants introduced during the sequencing process. We find that this filtering step reduces the number of false positive calls 50-fold without loss of true variant calls. After PELE we were able to validate 61.5% of the mutant calls that occurred at a frequency between 1 mutant call:100 wildtype calls and 1 mutant call:1000 wildtype calls in a pool of 288 fish. We then use high-resolution melt analysis to identify the single heterozygous mutation carrier in the 288-fish pool in which the mutation was identified. Using this NGS-TILLING protocol we validated 28 nonsense or splice site mutations in 20 genes, at a two-fold higher efficiency than using traditional Cel1 screening. We conclude that this approach significantly increases screening efficiency and accuracy at reduced cost and can be applied in a wide range of organisms.

  6. Molecular analysis using DHPLC of cystic fibrosis: increase of the mutation detection rate among the affected population in Central Italy

    Directory of Open Access Journals (Sweden)

    Nardone Anna

    2004-04-01

    Full Text Available Abstract Background Cystic fibrosis (CF is a multisystem disorder characterised by mutations of the CFTR gene, which encodes for an important component in the coordination of electrolyte movement across of epithelial cell membranes. Symptoms are pulmonary disease, pancreatic exocrine insufficiency, male infertility and elevated sweat concentrations. The CFTR gene has numerous mutations (>1000 and functionally important polymorphisms (>200. Early identification is important to provide appropriate therapeutic interventions, prognostic and genetic counselling and to ensure access to specialised medical services. However, molecular diagnosis by direct mutation screening has proved difficult in certain ethnic groups due to allelic heterogeneity and variable frequency of causative mutations. Methods We applied a gene scanning approach using DHPLC system for analysing specifically all CFTR exons and characterise sequence variations in a subgroup of CF Italian patients from the Lazio region (Central Italy characterised by an extensive allelic heterogeneity. Results We have identified a total of 36 different mutations representing 88% of the CF chromosomes. Among these are two novel CFTR mutations, including one missense (H199R and one microdeletion (4167delCTAAGCC. Conclusion Using this approach, we were able to increase our standard power rate of mutation detection of about 11% (77% vs. 88%.

  7. The use of high resolution melting analysis to detect Fabry mutations in heterozygous females via dry bloodspots.

    Science.gov (United States)

    Tai, Chang-Long; Liu, Mei-Ying; Yu, Hsiao-Chi; Chiang, Chiang-Chuan; Chiang, Hung; Suen, Jeng-Hung; Kao, Shu-Min; Huang, Yu-Hsiu; Wu, Tina Jui-Ting; Yang, Chia-Feng; Tsai, Fang-Chih; Lin, Ching-Yuang; Chang, Jan-Gowth; Chen, Hong-Duo; Niu, Dau-Ming

    2012-02-18

    As an X-linked genetic disorder, Fabry disease was first thought to affect males only, and females were generally considered to be asymptomatic carriers. However, recent research suggests that female carriers of Fabry disease may still develop vital organ damage causing severe morbidity and mortality. In the previous newborn screening, from 299,007 newborns, we identified a total of 20 different Fabry mutations and 121 newborns with Fabry mutations. However, we found that most female carriers are not detected by enzyme assays. A streamlined method for high resolution melting (HRM) analysis was designed to screen for GLA gene mutations using a same PCR and melting program. Primer sets were designed to cover the 7 exons and the Chinese common intronic mutation, IVS4+919G>A of GLA gene. The HRM analysis was successful in identifying heterozygous and hemizygous patients with the 20 surveyed mutations. We were also successful in using this method to test dry blood spots of newborns afflicted with Fabry mutations without having to determine DNA concentration before PCR amplification. The results of this study show that HRM could be a reliable and sensitive method for use in the rapid screening of females for GLA mutations. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. KRAS mutation detection in colorectal cancer by a commercially available gene chip array compares well with Sanger sequencing.

    Science.gov (United States)

    French, Deborah; Smith, Andrew; Powers, Martin P; Wu, Alan H B

    2011-08-17

    Binding of a ligand to the epidermal growth factor receptor (EGFR) stimulates various intracellular signaling pathways resulting in cell cycle progression, proliferation, angiogenesis and apoptosis inhibition. KRAS is involved in signaling pathways including RAF/MAPK and PI3K and mutations in this gene result in constitutive activation of these pathways, independent of EGFR activation. Seven mutations in codons 12 and 13 of KRAS comprise around 95% of the observed human mutations, rendering monoclonal antibodies against EGFR (e.g. cetuximab and panitumumab) useless in treatment of colorectal cancer. KRAS mutation testing by two different methodologies was compared; Sanger sequencing and AutoGenomics INFINITI® assay, on DNA extracted from colorectal cancers. Out of 29 colorectal tumor samples tested, 28 were concordant between the two methodologies for the KRAS mutations that were detected in both assays with the INFINITI® assay detecting a mutation in one sample that was indeterminate by Sanger sequencing and a third methodology; single nucleotide primer extension. This study indicates the utility of the AutoGenomics INFINITI® methodology in a clinical laboratory setting where technical expertise or access to equipment for DNA sequencing does not exist. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. The combination of heteroduplex analysis and protein truncation test for exact detection of the APC gene mutations

    International Nuclear Information System (INIS)

    Tomka, M.; Kirchhoff, T.; Stefurkova, V.; Zajac, V.; Kulcsar, L.

    1998-01-01

    Familial adenomatous polyposis (FAP) is usually associated with mutation in the adenomatous polyposis coli (APC) gene. To examine the occurrence of these mutations in the number of FAP suspected families from the whole Slovakia effectively, we have applied heteroduplex analysis (HDA) and protein truncation test (PTT) for the analyses of 2-5 base pair deletions and point mutations of the APC gene. In the analyzed exon 15 of the APC gene determined by the primers 15Efor-15Grev for HDA and 15ET7-15J3 for PTT more than 70% of mutations should be deletions [3, 12], which are detectable by HDA. In our collection of 5 FAP families mutations in the APC gene were found in families 10, 27 and 41 using HDA. By PTT test the formation of truncated APC protein in FAP families 2, 10, 16 and 27 were revealed. The necessity of combination of at least HDA and PTT techniques for exact detection of APC mutations in analyzed APC region is discussed. (authors)

  10. Endurance exercise rescues progeroid aging and induces systemic mitochondrial rejuvenation in mtDNA mutator mice

    Science.gov (United States)

    Safdar, Adeel; Bourgeois, Jacqueline M.; Ogborn, Daniel I.; Little, Jonathan P.; Hettinga, Bart P.; Akhtar, Mahmood; Thompson, James E.; Melov, Simon; Mocellin, Nicholas J.; Kujoth, Gregory C.; Prolla, Tomas A.; Tarnopolsky, Mark A.

    2011-01-01

    A causal role for mitochondrial DNA (mtDNA) mutagenesis in mammalian aging is supported by recent studies demonstrating that the mtDNA mutator mouse, harboring a defect in the proofreading-exonuclease activity of mitochondrial polymerase gamma, exhibits accelerated aging phenotypes characteristic of human aging, systemic mitochondrial dysfunction, multisystem pathology, and reduced lifespan. Epidemiologic studies in humans have demonstrated that endurance training reduces the risk of chronic diseases and extends life expectancy. Whether endurance exercise can attenuate the cumulative systemic decline observed in aging remains elusive. Here we show that 5 mo of endurance exercise induced systemic mitochondrial biogenesis, prevented mtDNA depletion and mutations, increased mitochondrial oxidative capacity and respiratory chain assembly, restored mitochondrial morphology, and blunted pathological levels of apoptosis in multiple tissues of mtDNA mutator mice. These adaptations conferred complete phenotypic protection, reduced multisystem pathology, and prevented premature mortality in these mice. The systemic mitochondrial rejuvenation through endurance exercise promises to be an effective therapeutic approach to mitigating mitochondrial dysfunction in aging and related comorbidities. PMID:21368114

  11. Inactivation and inducible oncogenic mutation of p53 in gene targeted pigs.

    Directory of Open Access Journals (Sweden)

    Simon Leuchs

    Full Text Available Mutation of the tumor suppressor p53 plays a major role in human carcinogenesis. Here we describe gene-targeted porcine mesenchymal stem cells (MSCs and live pigs carrying a latent TP53(R167H mutant allele, orthologous to oncogenic human mutant TP53(R175H and mouse Trp53(R172H, that can be activated by Cre recombination. MSCs carrying the latent TP53(R167H mutant allele were analyzed in vitro. Homozygous cells were p53 deficient, and on continued culture exhibited more rapid proliferation, anchorage independent growth, and resistance to the apoptosis-inducing chemotherapeutic drug doxorubicin, all characteristic of cellular transformation. Cre mediated recombination activated the latent TP53(R167H allele as predicted, and in homozygous cells expressed mutant p53-R167H protein at a level ten-fold greater than wild-type MSCs, consistent with the elevated levels found in human cancer cells. Gene targeted MSCs were used for nuclear transfer and fifteen viable piglets were produced carrying the latent TP53(R167H mutant allele in heterozygous form. These animals will allow study of p53 deficiency and expression of mutant p53-R167H to model human germline, or spontaneous somatic p53 mutation. This work represents the first inactivation and mutation of the gatekeeper tumor suppressor gene TP53 in a non-rodent mammal.

  12. The potential role of biotechnology and induced mutations in plant breeding

    International Nuclear Information System (INIS)

    Rubluo, A.; Brunner, I.; Palomino, G.; Rodriguez Garay, B.

    2001-01-01

    Although conventional techniques including mutation induction have increased the productivity of crops, the application of biotechnological tools such as tissue culture and molecular markers can speed up crop improvement. Through the application of in vitro culture techniques in Mammilaria san-angelensis, an ornamental cactus severely endangered, we proved through flow cytometry, genetic uniformity in massive in vitro derived plantlets and after irradiation we were able to regenerate it up to M1V4 generation. Solid mutants are expected if somatic embryos are treated with mutagenic agents due to its unicellular origin. Somatic embryogenesis was successfully achieved in Agave tequilana and after irradiation of embryogenic callus cultures, survivors were challenged with pathogenic crude bacterial extracts allowing the selection of resistant or tolerant individuals. Specially important are studies on neglected crops due to the interruption of its domestication and they are locally important for indigenous people as marginal crops. The trend now is to combine biotechnology and induced mutations to overcome problems with this highly promising crops. Chenopodium quinoa exhibits a strong constraint as food due to the undesirable production of saponins. The mutation induction strategy has enabled the reduction of this compounds in M5 generation, but further research is needed to overcome productivity and adaptability problems. Here the use of molecular markers (RAPDS) and flow cytometry techniques acquire relevance in the study of related species such as Chenopodium berlandieri in order to design an inter-specific breeding programme among selected mutants and outstanding local races to combine productivity, adaptability and grain quality

  13. Seventy five years of research on induced mutations with special reference to crop improvement in India

    International Nuclear Information System (INIS)

    Kharkwal, M.C.; Pawar, S.E.; Pandey, R.N.

    2001-01-01

    Mutation research programmes for crop improvement were initiated about seven decades ago, immediately after the discovery of mutagenic effects X-rays on Drosophila by Muller 1927 and barley and maize by Stadler in 1929. During fifties and sixties, several countries including China, India, the Netherlands, USA and Japan took up the task of crop improvement through mutation breeding approaches. By the end of the 20 th century about 2252 mutant varieties of crop plants including cereals, oil seeds, pulses, vegetables, fruits, fibres and ornamentals have been developed and released for cultivation worldwide. More than 60% of the varieties were released after 1985. While 1585 varieties were released as direct mutants, 667 varieties were developed by using mutants in cross breeding. Physical mutagens (X-rays, gamma rays, thermal and fast neutrons) account for the development of about 89% of the total varieties. Gamma rays alone were used to develop about 60% of the mutant varieties. India has made an appreciable contribution with the development of 301 mutant varieties (> 13% ) of forty four crop species. The mutant varieties have been improved for plant architecture, yield, quality and tolerance to biotic and abiotic stresses. Mutation breeding has made a significant contribution to the national economy of the countries like China, India, Japan, Pakistan and USA. Induced mutagenesis is gaining importance in plant molecular biology as a tool to identify and isolate gene and to study their structure and function. (author)

  14. Analysis of esterase isozyme and SSR for mutagenic progenies induced by space mutation in mustard

    International Nuclear Information System (INIS)

    Shen Jinjuan; Liu Yihua; Zhang Zhaorong; Ran Guangkui; Zhao Shouzhong; Xiao Li

    2012-01-01

    Seeds of five mustard (Brassica juncea Coss) varieties were carried into outer space by 'Shijian No.8' satellite. After five years' consecutive planting and selection, ten relatively stable mutant lines were obtained, which had significant variation in agronomic and economic characters. The mutant lines and their original varieties without space mutation treatment as control were studied by esterase isozyme and SSR analyses. Electrophoresis analysis of esterase isozymes indicated that there were differences between mutant lines and their controls in enzyme types and enzyme activity. Different mustard varieties had different enzymographs, and so did the mutants induced by space mutation, which shows different sensitivity among different mustard varieties. The SSR analysis showed that large differences were found in the SSR loci between mutant lines and their original variety, the variation frequency was between 9.52% and 57.14% with an average frequency of 26.19% for all the mutant lines. Among the mutant SSR loci, about 56.36% showed changes in band number and 43.64% in molecular weight. These results indicated that the ten mutant lines had large genetic difference in phenotype, genomic sequence and gene expression, and the outer space mutation would be an effective method to develop new mustard germplasm and variety. (authors)

  15. Mutation detection for inventories of traffic signs from street-level panoramic images

    Science.gov (United States)

    Hazelhoff, Lykele; Creusen, Ivo; De With, Peter H. N.

    2014-03-01

    Road safety is positively influenced by both adequate placement and optimal visibility of traffic signs. As their visibility degrades over time due to e.g. aging, vandalism, accidents and vegetation coverage, up-to-date inven­tories of traffic signs are highly attractive for preserving a high road safety. These inventories are performed in a semi-automatic fashion from street-level panoramic images, exploiting object detection and classification tech­niques. Next to performing inventories from scratch, these systems are also exploited for the efficient retrieval of situation changes by comparing the outcome of the automated system to a baseline inventory (e.g. performed in a previous year). This allows for specific manual interactions to the found changes, while skipping all unchanged situations, thereby resulting in a large efficiency gain. This work describes such a mutation detection approach, with special attention to re-identifying previously found signs. Preliminary results on a geographical area con­taining about 425 km of road show that 91.3% of the unchanged signs are re-identified, while the amount of found differences equals about 35% of the number of baseline signs. From these differences, about 50% correspond to physically changed traffic signs, next to false detections, misclassifications and missed signs. As a bonus, our approach directly results in the changed situations, which is beneficial for road sign maintenance.

  16. Simultaneous detection of hepatitis B virus genotypes and mutations associated with resistance to lamivudine, adefovir, and telbivudine by the polymerase chain reaction-ligase detection reaction

    Directory of Open Access Journals (Sweden)

    Yong-Zhong Wang

    Full Text Available OBJECTIVES: Detection of mutations associated to nucleos(tide analogs and hepatitis B virus (HBV genotyping are essential for monitoring treatment of HBV infection. We developed a multiplex polymerase chain reaction-ligase detection reaction (PCR-LDR assay for the rapid detection of HBV genotypes and mutations associated with lamivudine, adefovir, and telbivudine resistance in HBV-infected patients. METHODS: HBV templates were amplified by PCR, followed by LDR and electrophoresis on a sequencer. The assay was evaluated using plasmids that contained wild-type or mutant HBV sequences and 216 clinical samples. RESULTS: The PCR-LDR assay and sequencing gave comparable results for 158 of the 216 samples (73.1% with respect to mutation detection and genotyping. Complete agreement between the two methods was observed for all the samples (100% at codon 180 and codon 204. Concordant results were observed for 99.4% of the 158 samples at codon 181 and 98.7% at codon 236. The genotyping results were completely concordant between the PCR-LDR assay and sequencing. The PCR-LDR assay could detect a proportion of 1% mutant plasmid in a background of wild-type plasmid. CONCLUSION: The PCR-LDR assay is sensitive and specific for detection of HBV genotypes and drug resistance mutations, and could be helpful for decision making in the treatment of HBV infection.

  17. Identification of Maturity-Onset Diabetes of the Young Caused by Glucokinase Mutations Detected Using Whole-Exome Sequencing

    Directory of Open Access Journals (Sweden)

    Eun-Hee Cho

    2017-05-01

    Full Text Available Glucokinase maturity-onset diabetes of the young (GCK-MODY represents a distinct subgroup of MODY that does not require hyperglycemia-lowering treatment and has very few diabetes-related complications. Three patients from two families who presented with clinical signs of GCK-MODY were evaluated. Whole-exome sequencing was performed and the effects of the identified mutations were assessed using bioinformatics tools, such as PolyPhen-2, SIFT, and in silico modeling. We identified two mutations: p.Leu30Pro and p.Ser383Leu. In silico analyses predicted that these mutations result in structural conformational changes, protein destabilization, and thermal instability. Our findings may inform future GCK-MODY diagnosis; furthermore, the two mutations detected in two Korean families with GCK-MODY improve our understanding of the genetic basis of the disease.

  18. Vacuolar Protein Sorting Genes in Parkinson's Disease: A Re-appraisal of Mutations Detection Rate and Neurobiology of Disease.

    Science.gov (United States)

    Gambardella, Stefano; Biagioni, Francesca; Ferese, Rosangela; Busceti, Carla L; Frati, Alessandro; Novelli, Giuseppe; Ruggieri, Stefano; Fornai, Francesco

    2016-01-01

    Mammalian retromers play a critical role in protein trans-membrane sorting from endosome to the trans-Golgi network (TGN). Recently, retromer alterations have been related to the onset of Parkinson's Disease (PD) since the variant p.Asp620Asn in VPS35 (Vacuolar Protein Sorting 35) was identified as a cause of late onset PD. This variant causes a primary defect in endosomal trafficking and retromers formation. Other mutations in VPS genes have been reported in both sporadic and familial PD. These mutations are less defined. Understanding the specific prevalence of all VPS gene mutations is key to understand the relevance of retromers impairment in the onset of PD. A number of PD-related mutations despite affecting different biochemical systems (autophagy, mitophagy, proteasome, endosomes, protein folding), all converge in producing an impairment in cell clearance. This may explain how genetic predispositions to PD may derive from slightly deleterious VPS mutations when combined with environmental agents overwhelming the clearance of the cell. This manuscript reviews genetic data produced in the last 5 years to re-define the actual prevalence of VPS gene mutations in the onset of PD. The prevalence of p.Asp620Asn mutation in VPS35 is 0.286 of familial PD. This increases up to 0.548 when considering mutations affecting all VPS genes. This configures mutations in VPS genes as the second most frequent autosomal dominant PD genotype. This high prevalence, joined with increased awareness of the role played by retromers in the neurobiology of PD, suggests environmentally-induced VPS alterations as crucial in the genesis of PD.

  19. Vacuolar Protein Sorting Genes in Parkinson's Disease: A Re-appraisal of Mutations Detection Rate and Neurobiology of Disease

    Science.gov (United States)

    Gambardella, Stefano; Biagioni, Francesca; Ferese, Rosangela; Busceti, Carla L.; Frati, Alessandro; Novelli, Giuseppe; Ruggieri, Stefano; Fornai, Francesco

    2016-01-01

    Mammalian retromers play a critical role in protein trans-membrane sorting from endosome to the trans-Golgi network (TGN). Recently, retromer alterations have been related to the onset of Parkinson's Disease (PD) since the variant p.Asp620Asn in VPS35 (Vacuolar Protein Sorting 35) was identified as a cause of late onset PD. This variant causes a primary defect in endosomal trafficking and retromers formation. Other mutations in VPS genes have been reported in both sporadic and familial PD. These mutations are less defined. Understanding the specific prevalence of all VPS gene mutations is key to understand the relevance of retromers impairment in the onset of PD. A number of PD-related mutations despite affecting different biochemical systems (autophagy, mitophagy, proteasome, endosomes, protein folding), all converge in producing an impairment in cell clearance. This may explain how genetic predispositions to PD may derive from slightly deleterious VPS mutations when combined with environmental agents overwhelming the clearance of the cell. This manuscript reviews genetic data produced in the last 5 years to re-define the actual prevalence of VPS gene mutations in the onset of PD. The prevalence of p.Asp620Asn mutation in VPS35 is 0.286 of familial PD. This increases up to 0.548 when considering mutations affecting all VPS genes. This configures mutations in VPS genes as the second most frequent autosomal dominant PD genotype. This high prevalence, joined with increased awareness of the role played by retromers in the neurobiology of PD, suggests environmentally-induced VPS alterations as crucial in the genesis of PD. PMID:27932943

  20. Rapid detection of most frequent Slovenian germ-line mutations in BRCA1 gene using real-time PCR and melting curve analysis

    International Nuclear Information System (INIS)

    Novakovic, S.; Stegel, V.

    2005-01-01

    Background. Detection of inherited mutations in cancer susceptibility genes is of great importance in some types of cancers including the colorectal cancer (mutations of APC gene in familial adenomatous polyposis - FAP, mutations in mismatch repair genes in hereditary nonpolyposis colorectal cancer - HNPCC), malignant melanoma (mutations in CDKN2A and CDK4 genes) and breast cancer (mutations in BRCA1 and BRCA2 genes). Methods. This article presents the technical data for the detection of five mutations in BRCA1 gene in breast cancer patients and their relatives. The mutations - 1806C>T, 300T>G, 300T>A, 310G>A, 5382insC - were determined by the real-time PCR and the melting curve analysis. Results and conclusion. In comparison to direct sequencing, this method proved to be sensitive and rapid enough for the routine daily determination of mutations in DNA isolated from the peripheral blood. (author)

  1. Selective Breeding under Saline Stressed Conditions of Canola Mutations Induced by Gamma Rays

    International Nuclear Information System (INIS)

    Amer, I.M.; Moustafa, H.A.M.; Mansour, M.F.

    2009-01-01

    Mutation breeding program has been initiated for inducing canola mutations tolerance to saline stressed conditions for growing at harsh land in Egypt. Therefore, seed lots of three cultivars and exotic variety (Bactol, Serow 4, Serow 6 and Evita) were subjected to 100,400 and 600 Gy of gamma rays. Mass selection with 20 % intensity for high number of pods per plant has been done in each treatment in M2 generation. However, individually plants with high number of pods / plant were selected from each variety in M3 generation for test under saline stressed conditions at Ras Sudr region in M4 (8600 and 8300 ppm salinity for soil and irrigation, respectively). The obtained results revealed that eight mutated families from 12- test families in M4 generation surpassed their parents in seed yield / plant and related characters ( plant height ,fruiting zone length , No. of branches , No. of pods / plant ). In addition, the mutant F93 characterized by fast growing and non shuttering pods reflecting 50.4% over Evita control in seed yield/ plant. Twelve mutant lines in M5 represented the mutant families were grown in sandy-loam soil at Inshas region. The three mutant lines (L 22, L 38 and L 45) continuously surpassed their parents in seed yield and related characters, but the increases were less than the previous generation. The increase was 22.3 %, 38.7 % and 36.7 % over seed yield of respective parents. Moreover, mutant L66 exhibited an increase in its yield components in M5 at Inshas only, suggesting that gene expression and genomic structure extremely influenced by environmental factors. Genetic stability for the obtained mutations could be done at different environmental conditions in further studies

  2. Morphological mutations induced by gamma rays, ethylene imine and N-nitroso-N-ethyl urea in lentil (Lens culinaris medik.)

    International Nuclear Information System (INIS)

    Solanki, I.S.; Sharma, B.

    2003-01-01

    Dry and healthy seeds of a large seeded lentil cv, 'Precoz Selection', were treated with three doses each of gamma rays, ethylene imine (EI) and N-nitroso-N-ethyl urea (NEU). Based on the frequency of morphological mutations, the mutagens were arranged in the order: NEU > EI >. Gamma rays and dose-dependent relationship was observed in the case of gamma rays (5 kR 1 damage groups induced morphological mutations in the order: HH > HL > LH > LL. The morphological mutations included changes for growth habit, foliage, plant height and maturity and flowering behaviour. A mild relative mutagenic specificity and differences in mutability of genes for different traits were observed, In general the spectrum of morphological mutations was not influenced by the groups of M 1 damage, except that some mutation types occurred more frequently, than others in certain groups. (author)

  3. Pyrosequencing-Based Assays for Rapid Detection of HER2 and HER3 Mutations in Clinical Samples Uncover an E332E Mutation Affecting HER3 in Retroperitoneal Leiomyosarcoma

    Directory of Open Access Journals (Sweden)

    Paula González-Alonso

    2015-08-01

    Full Text Available Mutations in Human Epidermal Growth Factor Receptors (HER are associated with poor prognosis of several types of solid tumors. Although HER-mutation detection methods are currently available, such as Next-Generation Sequencing (NGS, alternative pyrosequencing allow the rapid characterization of specific mutations. We developed specific PCR-based pyrosequencing assays for identification of most prevalent HER2 and HER3 mutations, including S310F/Y, R678Q, L755M/P/S/W, V777A/L/M, 774-776 insertion, and V842I mutations in HER2, as well as M91I, V104M/L, D297N/V/Y, and E332E/K mutations in HER3. We tested 85 Formalin Fixed and Paraffin Embbeded (FFPE samples and we detected three HER2-V842I mutations in colorectal carcinoma (CRC, ovarian carcinoma, and pancreatic carcinoma patients, respectively, and a HER2-L755M mutation in a CRC specimen. We also determined the presence of a HER3-E332K mutation in an urothelial carcinoma sample, and two HER3-D297Y mutations, in both gastric adenocarcinoma and CRC specimens. The D297Y mutation was previously detected in breast and gastric tumors, but not in CRC. Moreover, we found a not-previously-described HER3-E332E synonymous mutation in a retroperitoneal leiomyosarcoma patient. The pyrosequencing assays presented here allow the detection and characterization of specific HER2 and HER3 mutations. These pyrosequencing assays might be implemented in routine diagnosis for molecular characterization of HER2/HER3 receptors as an alternative to complex NGS approaches.

  4. On the effect of hyperaldosteronism-inducing mutations in Na/K pumps.

    Science.gov (United States)

    Meyer, Dylan J; Gatto, Craig; Artigas, Pablo

    2017-11-06

    Primary aldosteronism, a condition in which too much aldosterone is produced and that leads to hypertension, is often initiated by an aldosterone-producing adenoma within the zona glomerulosa of the adrenal cortex. Somatic mutations of ATP1A1, encoding the Na/K pump α1 subunit, have been found in these adenomas. It has been proposed that a passive inward current transported by several of these mutant pumps is a "gain-of-function" activity that produces membrane depolarization and concomitant increases in aldosterone production. Here, we investigate whether the inward current through mutant Na/K pumps is large enough to induce depolarization of the cells that harbor them. We first investigate inward currents induced by these mutations in Xenopus Na/K pumps expressed in Xenopus oocytes and find that these inward currents are similar in amplitude to wild-type outward Na/K pump currents. Subsequently, we perform a detailed functional evaluation of the human Na/K pump mutants L104R, delF100-L104, V332G, and EETA963S expressed in Xenopus oocytes. By combining two-electrode voltage clamp with [ 3 H]ouabain binding, we measure the turnover rate of these inward currents and compare it to the turnover rate for outward current through wild-type pumps. We find that the turnover rate of the inward current through two of these mutants (EETA963S and L104R) is too small to induce significant cell depolarization. Electrophysiological characterization of another hyperaldosteronism-inducing mutation, G99R, reveals the absence of inward currents under many different conditions, including in the presence of the regulator FXYD1 as well as with mammalian ionic concentrations and body temperatures. Instead, we observe robust outward currents, but with significantly reduced affinities for intracellular Na + and extracellular K + Collectively, our results point to loss-of-function as the common mechanism for the hyperaldosteronism induced by these Na/K pump mutants. © 2017 Meyer et al.

  5. Tn5-induced pBS286 plasmid mutations blocking early stages of napthalene oxidation

    International Nuclear Information System (INIS)

    Kosheleva, I.A.; Tsoi, T.V.; Ivashina, T.V.; Selifonov, S.A.; Starovoitov, I.I.; Boronin, A.M.

    1988-01-01

    The authors present data on the further analysis of the structural and functional organization of the nah region of plasmid pBS286 controlling the constitutive oxidation of naphthalene by Pseudomonas putida cells. They have studied Tn5-induced mutations blocking early stages of naphthalene oxidation. They present and discuss data providing evidence that, in contrast to plasmid NAH7, the mechanism of regulation of the nahl operon of plasmid NPL-1, the parent plasmid of plasmid pBS286, with inducible synthesis of naphthalene dioxygenase can include elements of a negative control with participation of the regulatory locus R, located proximal to the structural nah genes and closely linked to or overlapped by the inverted control DNA segment (4.2 kb). They also present data on the possibility of regulation of the activity of the catechol-splitting meta-pathway genes with the participation of products of early stages of naphthalene oxidation

  6. The effects of MSH2 deficiency on spontaneous and radiation-induced mutation rates in the mouse germline

    International Nuclear Information System (INIS)

    Burr, Karen L-A.; Duyn-Goedhart, Annemarie van; Hickenbotham, Peter; Monger, Karen; Buul, Paul P.W. van; Dubrova, Yuri E.

    2007-01-01

    Mutation rates at two expanded simple tandem repeat (ESTR) loci were studied in the germline of mismatch repair deficient Msh2 knock-out mice. Spontaneous mutation rates in homozygous Msh2 -/- males were significantly higher than those in isogenic wild-type (Msh2 +/+ ) and heterozygous (Msh2 +/- ) mice. In contrast, the irradiated Msh2 -/- mice did not show any detectable increases in their mutation rate, whereas significant ESTR mutation induction was observed in the irradiated Msh2 +/+ and Msh2 +/- animals. Considering these data and the results of other publications, we propose that the Msh2-deficient mice possess a mutator phenotype in their germline and somatic tissues while the loss of a single Msh2 allele does not affect the stability of heterozygotes

  7. Induced mutagenesis as a source of new mutations in maize (Zea mays L.)

    International Nuclear Information System (INIS)

    Mashnenkov, A.S.

    1990-01-01

    Full text: Seed samples of 9 inbreds were treated with MNU. Mutant individuals were visually selected in M 2 and M 3 . Mutability was determined in 100 loci by crossing induced mutants with some well-known natural mutants obtained from the U.S. Association of Corn Geneticists. Only viable mutants characterised with distinct stable traits connected with kernel texture and mature plant were taken for tests. Mapping of the expected new mutants was realised through A-B translocations and marker lines. Evaluation of the mutant alleles' effect on yield and quality of biomass in inbreds and heterotic hybrids was done by the standard methods. The results show the ability of artificial mutagens to induce mutations in previously known loci. The genotype of the inbreds greatly affects the probability of mutation occurrence in a new locus. Due to the mutagen effect, independently inherited complexes of traits or naturally polygenic traits may become monogenic. This results in simplified inheritance, in an increase in heritability and thus in high effectiveness of selection. (author)

  8. Induced mutagenesis as a source of new mutations in maize (Zea mays L.)

    Energy Technology Data Exchange (ETDEWEB)

    Mashnenkov, A S [Krasnodar Research Institute of Agriculture, Krasnodar (USSR)

    1990-01-01

    Full text: Seed samples of 9 inbreds were treated with MNU. Mutant individuals were visually selected in M{sub 2} and M{sub 3}. Mutability was determined in 100 loci by crossing induced mutants with some well-known natural mutants obtained from the U.S. Association of Corn Geneticists. Only viable mutants characterised with distinct stable traits connected with kernel texture and mature plant were taken for tests. Mapping of the expected new mutants was realised through A-B translocations and marker lines. Evaluation of the mutant alleles' effect on yield and quality of biomass in inbreds and heterotic hybrids was done by the standard methods. The results show the ability of artificial mutagens to induce mutations in previously known loci. The genotype of the inbreds greatly affects the probability of mutation occurrence in a new locus. Due to the mutagen effect, independently inherited complexes of traits or naturally polygenic traits may become monogenic. This results in simplified inheritance, in an increase in heritability and thus in high effectiveness of selection. (author)

  9. Molecular and genetic characterization of a radiation-induced structural rearrangement in mouse chromosome 2 causing mutations at the limb deformity and agouti loci

    International Nuclear Information System (INIS)

    Woychik, R.P.; Generoso, W.M.; Russell, L.B.; Cain, K.T.; Cacheiro, N.L.; Bultman, S.J.; Selby, P.B.; Dickinson, M.E.; Hogan, B.L.

    1990-01-01

    Molecular characterization of mutations in the mouse, particularly those involving agent-induced major structural alterations, is proving to be useful for correlating the structure and expression of individual genes with their function in the whole organism. Here we present the characterization of a radiation-induced mutation that simultaneously generated distinct alleles of both the limb deformity (ld) and agouti (a) loci, two developmentally important regions of chromosome 2 normally separated by 20 centimorgans. Cytogenetic analysis revealed that an interstitial segment of chromosome 17 (17B- 17C; or, possibly, 17A2-17B) had been translocated into the distal end of chromosome 2, resulting in a smaller-than-normal chromosome 17 (designated 17del) and a larger form of chromosome 2 designated 2(17). Additionally, a large interstitial segment of the 2(17) chromosome, immediately adjacent and proximal to the insertion site, did not match bands 2E4-2H1 at corresponding positions on a normal chromosome 2. Molecular analysis detected a DNA rearrangement in which a portion of the ld locus was joined to sequences normally tightly linked to the a locus. This result, along with the genetic and cytogenetic data, suggests that the alleles of ld and a in this radiation-induced mutation, designated ldIn2 and ajIn2, were associated with DNA breaks caused by an inversion of an interstitial segment in the 2(17) chromosome

  10. DNA replication in necessary for fixing induced mutations to streptomycin-resistance in UV-irradiated Escherichia coli cells

    Energy Technology Data Exchange (ETDEWEB)

    Dubinin, N P; Filippov, V D

    1986-01-01

    A suspension of E.coli cells has been subjected to UV radiation, then it has been incubated in the growth medium for 15 min. After that one of the portions was incubated with nalidixic acid (NA), and the other one without it in the presence of an antibiotic. Frequency of mutations depending on or irrespective of photoactivation, has been determined. Dependence of Str mutation fixing, induced by low UV radiation doses, on DNA synthesis is determined. Results indicate that both photoreactivation of mutations and its senstivity to mfd system are simultaneously lost.

  11. Sequential mutations in Notch1, Fbxw7, and Tp53 in radiation-induced mouse thymic lymphomas.

    Science.gov (United States)

    Jen, Kuang-Yu; Song, Ihn Young; Banta, Karl Luke; Wu, Di; Mao, Jian-Hua; Balmain, Allan

    2012-01-19

    T-cell acute lymphoblastic lymphomas commonly demonstrate activating Notch1 mutations as well as mutations or deletions in Fbxw7. However, because Fbxw7 targets Notch1 for degradation, genetic alterations in these genes are expected to be mutually exclusive events in lymphomagenesis. Previously, by using a radiation-induced Tp53-deficient mouse model for T-cell acute lymphoblastic lymphoma, we reported that loss of heterozygosity at the Fbxw7 locus occurs frequently in a Tp53-dependent manner. In the current study, we show that these thymic lymphomas also commonly exhibit activating Notch1 mutations in the proline-glutamic acid-serine-threonine (PEST) domain. Moreover, concurrent activating Notch1 PEST domain mutations and single-copy deletions at the Fbxw7 locus occur with high frequency in the same individual tumors, indicating that these changes are not mutually exclusive events. We further demonstrate that although Notch1 PEST domain mutations are independent of Tp53 status, they are completely abolished in mice with germline Fbxw7 haploinsufficiency. Therefore, Notch1 PEST domain mutations only occur when Fbxw7 expression levels are intact. These data suggest a temporal sequence of mutational events involving these important cancer-related genes, with Notch1 PEST domain mutations occurring first, followed by Fbxw7 deletion, and eventually by complete loss of Tp53.

  12. A rare variant of α 1 antitrypsin mutations detected in Vietnamese children with liver disease.

    Science.gov (United States)

    Hoàng, Thu Hà; Phạm, Thiên Ngọc; Nguyễn, Gia Khánh; Lê, Quang Huấn

    2013-07-01

    Alpha 1 antitrypsin (A1AT) is the major plasma serine protease inhibitor that is produced in liver cells. A1AT deficiency is recognized globally as a common genetic cause of liver disease in children, which results from mutations in the SERine Protease INhibitor A1 (SERPINA1) gene. The importance of A1AT deficiency in Viet Nam is unclear. The aim of this study was to determine the A1AT variants present in paediatric patients with liver diseases in order to clarify whether A1AT deficiency is present in Viet Nam. A1AT studies were carried out in 130 children with liver disease of indeterminate aetiology. A1AT levels were determined by immunoturbidimetry. Phenotype analysis of A1AT was performed by isoelectric focusing (IEF) in all patients. Genotype analyses to determine A1AT mutations were performed by direct sequencing. We identified a rare variant of A1AT named Zbristol. The Zbristol appeared to be deficient in the plasma to about the same degree as the PI S protein resulting in low concentration of A1AT in one of these two Vietnamese patients. No other deficient A1AT allele was detected, although 11 patients (8.5%) showed a reduced serum concentration of A1AT. These are the first two cases of a rare A1AT deficiency allele to be found in Viet Nam clearly inferring that A1AT deficiency is not just a disease of Caucasians. As such, the laboratory diagnosis of A1AT deficiency including A1AT concentration determination and phenotype and genotype testing should form part of the routine differential diagnosis of paediatric liver disease of indeterminate aetiology in Vietnamese patients.

  13. New comprehensive denaturing-gradient-gel-electrophoresis assay for KRAS mutation detection applied to paraffin-embedded tumours

    NARCIS (Netherlands)

    Hayes, VM; Westra, JL; Verlind, E; Bleeker, W; Plukker, JT; Hofstra, RMW; Buys, CHCM

    2000-01-01

    A comprehensive mutation detection assay is presented for the entire coding region and all splice site junctions of the KRAS oncogene. The assay is based on denaturing gradient gel electrophoresis and applicable to archival paraffin-embedded tumour material. All KRAS amplicons are analysed within

  14. An inducible mouse model of podocin-mutation-related nephrotic syndrome.

    Directory of Open Access Journals (Sweden)

    Mansoureh Tabatabaeifar

    Full Text Available Mutations in the NPHS2 gene, encoding podocin, cause hereditary nephrotic syndrome. The most common podocin mutation, R138Q, is associated with early disease onset and rapid progression to end-stage renal disease. Knock-in mice carrying a R140Q mutation, the mouse analogue of human R138Q, show developmental arrest of podocytes and lethal renal failure at neonatal age. Here we created a conditional podocin knock-in model named NPHS2 R140Q/-, using a tamoxifen-inducible Cre recombinase, which permits to study the effects of the mutation in postnatal life. Within the first week of R140Q hemizygosity induction the animals developed proteinuria, which peaked after 4-5 weeks. Subsequently the animals developed progressive renal failure, with a median survival time of 12 (95% CI: 11-13 weeks. Foot process fusion was observed within one week, progressing to severe and global effacement in the course of the disease. The number of podocytes per glomerulus gradually diminished to 18% compared to healthy controls 12-16 weeks after induction. The fraction of segmentally sclerosed glomeruli was 25%, 85% and 97% at 2, 4 and 8 weeks, respectively. Severe tubulointerstitial fibrosis was present at later disease stage and was correlated quantitatively with the level of proteinuria at early disease stages. While R140Q podocin mRNA expression was elevated, protein abundance was reduced by more than 50% within one week following induction. Whereas miRNA21 expression persistently increased during the first 4 weeks, miRNA-193a expression peaked 2 weeks after induction. In conclusion, the inducible R140Q-podocin mouse model is an auspicious model of the most common genetic cause of human nephrotic syndrome, with a spontaneous disease course strongly reminiscent of the human disorder. This model constitutes a valuable tool to test the efficacy of novel pharmacological interventions aimed to improve podocyte function and viability and attenuate proteinuria

  15. Genetic signatures from amplification profiles characterize DNA mutation in somatic and radiation-induced sports of chrysanthemum

    International Nuclear Information System (INIS)

    Trigiano, R.N.; Scott, M.C.; Caetano-Anolles, G.

    1998-01-01

    The chrysanthemum (Dendranthema grandiflora Tzvelev.) cultivars 'Dark Charm', 'Salmon Charm', 'Coral Charm' and 'Dark Bronze Charm' are either radiation-induced mutants or spontaneous sports of 'Charm' and constitute a family or series of plants that primarily differ in flower color. These cultivars, which were difficult to differentiate genetically by DNA amplification fingerprinting (DAF), were easily identified by using arbitrary signatures from amplification profiles (ASAP). Genomic DNA was first amplified with three standard octamer arbitrary primers, all of which produced monomorphic profiles. Products from each of these DNA fingerprints were subsequently reamplified using four minihairpin decamer primers. The 12 primer combinations produced signatures containing approximately 37% polymorphic character loci, which were used to estimate genetic relationships between cultivars. Forty-six (32%) unique amplification products were associated with individual cultivars. The number of ASAP polymorphisms detected provided an estimate of the mutation rate in the mutant cultivars, ranging from 0.03% to 1.6% of nucleotide changes within an average of 18 kb of arbitrary amplified DAF sequence. The ASAP technique permits the clear genetic identification of somatic mutants and radiation-induced sports that are genetically highly homogeneous and should facilitate marker assisted breeding and protection of plant breeders rights of varieties or cultivars

  16. Experimental platform utilising melting curve technology for detection of mutations in Mycobacterium tuberculosis isolates.

    Science.gov (United States)

    Broda, Agnieszka; Nikolayevskyy, Vlad; Casali, Nicki; Khan, Huma; Bowker, Richard; Blackwell, Gemma; Patel, Bhakti; Hume, James; Hussain, Waqar; Drobniewski, Francis

    2018-04-20

    Tuberculosis (TB) remains one of the most deadly infections with approximately a quarter of cases not being identified and/or treated mainly due to a lack of resources. Rapid detection of TB or drug-resistant TB enables timely adequate treatment and is a cornerstone of effective TB management. We evaluated the analytical performance of a single-tube assay for multidrug-resistant TB (MDR-TB) on an experimental platform utilising RT-PCR and melting curve analysis that could potentially be operated as a point-of-care (PoC) test in resource-constrained settings with a high burden of TB. Firstly, we developed and evaluated the prototype MDR-TB assay using specimens extracted from well-characterised TB isolates with a variety of distinct rifampicin and isoniazid resistance conferring mutations and nontuberculous Mycobacteria (NTM) strains. Secondly, we validated the experimental platform using 98 clinical sputum samples from pulmonary TB patients collected in high MDR-TB settings. The sensitivity of the platform for TB detection in clinical specimens was 75% for smear-negative and 92.6% for smear-positive sputum samples. The sensitivity of detection for rifampicin and isoniazid resistance was 88.9 and 96.0% and specificity was 87.5 and 100%, respectively. Observed limitations in sensitivity and specificity could be resolved by adjusting the sample preparation methodology and melting curve recognition algorithm. Overall technology could be considered a promising PoC methodology especially in resource-constrained settings based on its combined accuracy, convenience, simplicity, speed, and cost characteristics.

  17. Detection of Greenhouse-Gas-Induced Climatic Change

    Energy Technology Data Exchange (ETDEWEB)

    Jones, P.D.; Wigley, T.M.L.

    1998-05-26

    The objective of this report is to assemble and analyze instrumental climate data and to develop and apply climate models as a basis for (1) detecting greenhouse-gas-induced climatic change, and (2) validation of General Circulation Models.

  18. Efficacy of Exome-Targeted Capture Sequencing to Detect Mutations in Known Cerebellar Ataxia Genes.

    Science.gov (United States)

    Coutelier, Marie; Hammer, Monia B; Stevanin, Giovanni; Monin, Marie-Lorraine; Davoine, Claire-Sophie; Mochel, Fanny; Labauge, Pierre; Ewenczyk, Claire; Ding, Jinhui; Gibbs, J Raphael; Hannequin, Didier; Melki, Judith; Toutain, Annick; Laugel, Vincent; Forlani, Sylvie; Charles, Perrine; Broussolle, Emmanuel; Thobois, Stéphane; Afenjar, Alexandra; Anheim, Mathieu; Calvas, Patrick; Castelnovo, Giovanni; de Broucker, Thomas; Vidailhet, Marie; Moulignier, Antoine; Ghnassia, Robert T; Tallaksen, Chantal; Mignot, Cyril; Goizet, Cyril; Le Ber, Isabelle; Ollagnon-Roman, Elisabeth; Pouget, Jean; Brice, Alexis; Singleton, Andrew; Durr, Alexandra

    2018-05-01

    Molecular diagnosis is difficult to achieve in disease groups with a highly heterogeneous genetic background, such as cerebellar ataxia (CA). In many patients, candidate gene sequencing or focused resequencing arrays do not allow investigators to reach a genetic conclusion. To assess the efficacy of exome-targeted capture sequencing to detect mutations in genes broadly linked to CA in a large cohort of undiagnosed patients and to investigate their prevalence. Three hundred nineteen index patients with CA and without a history of dominant transmission were included in the this cohort study by the Spastic Paraplegia and Ataxia Network. Centralized storage was in the DNA and cell bank of the Brain and Spine Institute, Salpetriere Hospital, Paris, France. Patients were classified into 6 clinical groups, with the largest being those with spastic ataxia (ie, CA with pyramidal signs [n = 100]). Sequencing was performed from January 1, 2014, through December 31, 2016. Detected variants were classified as very probably or definitely causative, possibly causative, or of unknown significance based on genetic evidence and genotype-phenotype considerations. Identification of variants in genes broadly linked to CA, classified in pathogenicity groups. The 319 included patients had equal sex distribution (160 female [50.2%] and 159 male patients [49.8%]; mean [SD] age at onset, 27.9 [18.6] years). The age at onset was younger than 25 years for 131 of 298 patients (44.0%) with complete clinical information. Consanguinity was present in 101 of 298 (33.9%). Very probable or definite diagnoses were achieved for 72 patients (22.6%), with an additional 19 (6.0%) harboring possibly pathogenic variants. The most frequently mutated genes were SPG7 (n = 14), SACS (n = 8), SETX (n = 7), SYNE1 (n = 6), and CACNA1A (n = 6). The highest diagnostic rate was obtained for patients with an autosomal recessive CA with oculomotor apraxia-like phenotype (6 of 17 [35.3%]) or

  19. MLPA based detection of mutations in the dystrophin gene of 180 Polish families with Duchenne/Becker muscular dystrophy.

    Science.gov (United States)

    Zimowski, Janusz G; Massalska, Diana; Holding, Mariola; Jadczak, Sylwia; Fidziańska, Elżbieta; Lusakowska, Anna; Kostera-Pruszczyk, Anna; Kamińska, Anna; Zaremba, Jacek

    2014-01-01

    Duchenne/Becker muscular dystrophy (DMD/BMD) is a recessive, X-linked disorder caused by a mutation in the dystrophin gene. Deletions account for approximately 60-65% of mutations, duplications for 5-10%. The remaining cases are mainly point mutations. According to Monaco theory clinical form of the disease depends on maintaining or disrupting the reading frame. The purpose of the study was to determine frequency and location of deletions and duplications in the dystrophin gene, to determine the compliance between maintaining/disrupting the reading frame and clinical form of the disease and to check the effectiveness of MLPA (multiplex ligation-dependent probe amplification) in the detection of these mutations in hemizygous patients and heterozygous female carriers. The material is composed of combined results of molecular diagnosis carried out in years 2009-2012 in 180 unrelated patients referred with the diagnosis of DMD/BMD tested by use of MLPA. We identified 110 deletions, 22 duplication (in one patient two different duplications were detected) and 2 point mutations. Deletions involved mainly exons 45-54 and 3-21, whereas most duplications involved exons 3-18. The compliance with Monaco theory was 95% for deletions and 76% for duplications. Most of mutations in the dystrophin gene were localized in the hot spots - different for deletions and duplications. MLPA enabled their quick identification, exact localization and determination whether or not they maintained or disrupted the reading frame. MLPA was also effective in detection of deletions and duplications in female carriers. Copyright © 2014 Polish Neurological Society. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  20. A new sieving matrix for DNA sequencing, genotyping and mutation detection and high-throughput genotyping with a 96-capillary array system

    Energy Technology Data Exchange (ETDEWEB)

    Gao, David [Iowa State Univ., Ames, IA (United States)

    1999-11-08

    Capillary electrophoresis has been widely accepted as a fast separation technique in DNA analysis. In this dissertation, a new sieving matrix is described for DNA analysis, especially DNA sequencing, genetic typing and mutation detection. A high-throughput 96 capillary array electrophoresis system was also demonstrated for simultaneous multiple genotyping. The authors first evaluated the influence of different capillary coatings on the performance of DNA sequencing. A bare capillary was compared with a DB-wax, an FC-coated and a polyvinylpyrrolidone dynamically coated capillary with PEO as sieving matrix. It was found that covalently-coated capillaries had no better performance than bare capillaries while PVP coating provided excellent and reproducible results. The authors also developed a new sieving Matrix for DNA separation based on commercially available poly(vinylpyrrolidone) (PVP). This sieving matrix has a very low viscosity and an excellent self-coating effect. Successful separations were achieved in uncoated capillaries. Sequencing of M13mp18 showed good resolution up to 500 bases in treated PVP solution. Temperature gradient capillary electrophoresis and PVP solution was applied to mutation detection. A heteroduplex sample and a homoduplex reference were injected during a pair of continuous runs. A temperature gradient of 10 C with a ramp of 0.7 C/min was swept throughout the capillary. Detection was accomplished by laser induced fluorescence detection. Mutation detection was performed by comparing the pattern changes between the homoduplex and the heteroduplex samples. High throughput, high detection rate and easy operation were achieved in this system. They further demonstrated fast and reliable genotyping based on CTTv STR system by multiple-capillary array electrophoresis. The PCR products from individuals were mixed with pooled allelic ladder as an absolute standard and coinjected with a 96-vial tray. Simultaneous one-color laser-induced fluorescence

  1. LEOPARD syndrome-associated SHP2 mutation confers leanness and protection from diet-induced obesity.

    Science.gov (United States)

    Tajan, Mylène; Batut, Aurélie; Cadoudal, Thomas; Deleruyelle, Simon; Le Gonidec, Sophie; Saint Laurent, Céline; Vomscheid, Maëlle; Wanecq, Estelle; Tréguer, Karine; De Rocca Serra-Nédélec, Audrey; Vinel, Claire; Marques, Marie-Adeline; Pozzo, Joffrey; Kunduzova, Oksana; Salles, Jean-Pierre; Tauber, Maithé; Raynal, Patrick; Cavé, Hélène; Edouard, Thomas; Valet, Philippe; Yart, Armelle

    2014-10-21

    LEOPARD syndrome (multiple Lentigines, Electrocardiographic conduction abnormalities, Ocular hypertelorism, Pulmonary stenosis, Abnormal genitalia, Retardation of growth, sensorineural Deafness; LS), also called Noonan syndrome with multiple lentigines (NSML), is a rare autosomal dominant disorder associating various developmental defects, notably cardiopathies, dysmorphism, and short stature. It is mainly caused by mutations of the PTPN11 gene that catalytically inactivate the tyrosine phosphatase SHP2 (Src-homology 2 domain-containing phosphatase 2). Besides its pleiotropic roles during development, SHP2 plays key functions in energetic metabolism regulation. However, the metabolic outcomes of LS mutations have never been examined. Therefore, we performed an extensive metabolic exploration of an original LS mouse model, expressing the T468M mutation of SHP2, frequently borne by LS patients. Our results reveal that, besides expected symptoms, LS animals display a strong reduction of adiposity and resistance to diet-induced obesity, associated with overall better metabolic profile. We provide evidence that LS mutant expression impairs adipogenesis, triggers energy expenditure, and enhances insulin signaling, three features that can contribute to the lean phenotype of LS mice. Interestingly, chronic treatment of LS mice with low doses of MEK inhibitor, but not rapamycin, resulted in weight and adiposity gains. Importantly, preliminary data in a French cohort of LS patients suggests that most of them have lower-than-average body mass index, associated, for tested patients, with reduced adiposity. Altogether, these findings unravel previously unidentified characteristics for LS, which could represent a metabolic benefit for patients, but may also participate to the development or worsening of some traits of the disease. Beyond LS, they also highlight a protective role of SHP2 global LS-mimicking modulation toward the development of obesity and associated disorders.

  2. Sensitivity and Frequencies of Dystrophin Gene Mutations in Thai DMD/BMD Patients As Detected by Multiplex PCR

    Directory of Open Access Journals (Sweden)

    Thanyachai Sura

    2008-01-01

    Full Text Available Background: Duchenne muscular dystrophy (DMD, a lethal X-linked disease affecting 1 in 3500 male births, and its more benign variant, Becker muscular dystrophy (BMD, are caused by mutations in the dystrophin gene. Because of its large size, analysing the whole gene is impractical. Methods have been developed to detect the commonest mutations i.e. the deletions of the exons. Although these tests are highly specific, their sensitivity is inherently limited by the prevalence of deletions, which differs among different populations.

  3. Effect of AC magnetic fields on ultraviolet light-induced mutation and mitotic recombination in Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Ager, D.D.; Radul, J.A.

    1994-01-01

    The ability of 60-Hz magnetic fields to induce genetic damage in Saccharomyces cerevisiae was studied. The frequencies of induced mutation, gene conversion, and reciprocal mitotic crossing over were measured for exposures to 1-millitesla magnetic fields alone or in combination with various preliminary exposures to 254-nm ultraviolet light at intensities of 2-50 J/m 2 . These experiments were performed using a repair-proficient strain as well as a strain incapable of excising ultraviolet-induced thymine dimers. Magnetic field exposures did not induce mutation, gene conversion, or reciprocal mitotic crossing over in either of these strains, nor did the fields influence the frequencies of ultraviolet-induced genetic events. 32 refs., 4 tabs

  4. Preliminary studies on DNA retardation by MutS applied to the detection of point mutations in clinical samples

    International Nuclear Information System (INIS)

    Stanislawska-Sachadyn, Anna; Paszko, Zygmunt; Kluska, Anna; Skasko, Elzibieta; Sromek, Maria; Balabas, Aneta; Janiec-Jankowska, Aneta; Wisniewska, Alicja; Kur, Jozef; Sachadyn, Pawel

    2005-01-01

    MutS ability to bind DNA mismatches was applied to the detection of point mutations in PCR products. MutS recognized mismatches from single up to five nucleotides and retarded the electrophoretic migration of mismatched DNA. The electrophoretic detection of insertions/deletions above three nucleotides is also possible without MutS, thanks to the DNA mobility shift caused by the presence of large insertion/deletion loops in the heteroduplex DNA. Thus, the method enables the search for a broad range of mutations: from single up to several nucleotides. The mobility shift assays were carried out in polyacrylamide gels stained with SYBR-Gold. One assay required 50-200 ng of PCR product and 1-3 μg of Thermus thermophilus his 6 -MutS protein. The advantages of this approach are: the small amounts of DNA required for the examination, simple and fast staining, no demand for PCR product purification, no labelling and radioisotopes required. The method was tested in the detection of cancer predisposing mutations in RET, hMSH2, hMLH1, BRCA1, BRCA2 and NBS1 genes. The approach appears to be promising in screening for unknown point mutations

  5. Evaluation of Nine Somatic Variant Callers for Detection of Somatic Mutations in Exome and Targeted Deep Sequencing Data.

    Directory of Open Access Journals (Sweden)

    Anne Bruun Krøigård

    Full Text Available Next generation sequencing is extensively applied to catalogue somatic mutations in cancer, in research settings and increasingly in clinical settings for molecular diagnostics, guiding therapy decisions. Somatic variant callers perform paired comparisons of sequencing data from cancer tissue and matched normal tissue in order to detect somatic mutations. The advent of many new somatic variant callers creates a need for comparison and validation of the tools, as no de facto standard for detection of somatic mutations exists and only limited comparisons have been reported. We have performed a comprehensive evaluation using exome sequencing and targeted deep sequencing data of paired tumor-normal samples from five breast cancer patients to evaluate the performance of nine publicly available somatic variant callers: EBCall, Mutect, Seurat, Shimmer, Indelocator, Somatic Sniper, Strelka, VarScan 2 and Virmid for the detection of single nucleotide mutations and small deletions and insertions. We report a large variation in the number of calls from the nine somatic variant callers on the same sequencing data and highly variable agreement. Sequencing depth had markedly diverse impact on individual callers, as for some callers, increased sequencing depth highly improved sensitivity. For SNV calling, we report EBCall, Mutect, Virmid and Strelka to be the most reliable somatic variant callers for both exome sequencing and targeted deep sequencing. For indel calling, EBCall is superior due to high sensitivity and robustness to changes in sequencing depths.

  6. Evaluation of Nine Somatic Variant Callers for Detection of Somatic Mutations in Exome and Targeted Deep Sequencing Data.

    Science.gov (United States)

    Krøigård, Anne Bruun; Thomassen, Mads; Lænkholm, Anne-Vibeke; Kruse, Torben A; Larsen, Martin Jakob

    2016-01-01

    Next generation sequencing is extensively applied to catalogue somatic mutations in cancer, in research settings and increasingly in clinical settings for molecular diagnostics, guiding therapy decisions. Somatic variant callers perform paired comparisons of sequencing data from cancer tissue and matched normal tissue in order to detect somatic mutations. The advent of many new somatic variant callers creates a need for comparison and validation of the tools, as no de facto standard for detection of somatic mutations exists and only limited comparisons have been reported. We have performed a comprehensive evaluation using exome sequencing and targeted deep sequencing data of paired tumor-normal samples from five breast cancer patients to evaluate the performance of nine publicly available somatic variant callers: EBCall, Mutect, Seurat, Shimmer, Indelocator, Somatic Sniper, Strelka, VarScan 2 and Virmid for the detection of single nucleotide mutations and small deletions and insertions. We report a large variation in the number of calls from the nine somatic variant callers on the same sequencing data and highly variable agreement. Sequencing depth had markedly diverse impact on individual callers, as for some callers, increased sequencing depth highly improved sensitivity. For SNV calling, we report EBCall, Mutect, Virmid and Strelka to be the most reliable somatic variant callers for both exome sequencing and targeted deep sequencing. For indel calling, EBCall is superior due to high sensitivity and robustness to changes in sequencing depths.

  7. Whole-exome sequencing for mutation detection in pediatric disorders of insulin secretion: Maturity onset diabetes of the young and congenital hyperinsulinism.

    Science.gov (United States)

    Johnson, S R; Leo, P J; McInerney-Leo, A M; Anderson, L K; Marshall, M; McGown, I; Newell, F; Brown, M A; Conwell, L S; Harris, M; Duncan, E L

    2018-06-01

    To assess the utility of whole-exome sequencing (WES) for mutation detection in maturity-onset diabetes of the young (MODY) and congenital hyperinsulinism (CHI). MODY and CHI are the two commonest monogenic disorders of glucose-regulated insulin secretion in childhood, with 13 causative genes known for MODY and 10 causative genes identified for CHI. The large number of potential genes makes comprehensive screening using traditional methods expensive and time-consuming. Ten subjects with MODY and five with CHI with known mutations underwent WES using two different exome capture kits (Nimblegen SeqCap EZ Human v3.0 Exome Enrichment Kit, Nextera Rapid Capture Exome Kit). Analysis was blinded to previously identified mutations, and included assessment for large deletions. The target capture of five exome capture technologies was also analyzed using sequencing data from >2800 unrelated samples. Four of five MODY mutations were identified using Nimblegen (including a large deletion in HNF1B). Although targeted, one mutation (in INS) had insufficient coverage for detection. Eleven of eleven mutations (six MODY, five CHI) were identified using Nextera Rapid (including the previously missed mutation). On reconciliation, all mutations concorded with previous data and no additional variants in MODY genes were detected. There were marked differences in the performance of the capture technologies. WES can be useful for screening for MODY/CHI mutations, detecting both point mutations and large deletions. However, capture technologies require careful selection. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. A novel radiation-induced p53 mutation is not implicated in radiation resistance via a dominant-negative effect.

    Directory of Open Access Journals (Sweden)

    Yunguang Sun

    Full Text Available Understanding the mutations that confer radiation resistance is crucial to developing mechanisms to subvert this resistance. Here we describe the creation of a radiation resistant cell line and characterization of a novel p53 mutation. Treatment with 20 Gy radiation was used to induce mutations in the H460 lung cancer cell line; radiation resistance was confirmed by clonogenic assay. Limited sequencing was performed on the resistant cells created and compared to the parent cell line, leading to the identification of a novel mutation (del at the end of the DNA binding domain of p53. Levels of p53, phospho-p53, p21, total caspase 3 and cleaved caspase 3 in radiation resistant cells and the radiation susceptible (parent line were compared, all of which were found to be similar. These patterns held true after analysis of p53 overexpression in H460 cells; however, H1299 cells transfected with mutant p53 did not express p21, whereas those given WT p53 produced a significant amount, as expected. A luciferase assay demonstrated the inability of mutant p53 to bind its consensus elements. An MTS assay using H460 and H1299 cells transfected with WT or mutant p53 showed that the novel mutation did not improve cell survival. In summary, functional characterization of a radiation-induced p53 mutation in the H460 lung cancer cell line does not implicate it in the development of radiation resistance.

  9. Sequencing analysis of mutations induced by N-ethyl-N-nitrosourea at different sampling times in mouse bone marrow.

    Science.gov (United States)

    Wang, Jianyong; Chen, Tao

    2010-03-01

    In our previous study (Wang et al., 2004, Toxicol. Sci. 82: 124-128), we observed that the cII gene mutant frequency (MF) in the bone marrow of Big Blue mice showed significant increase as early as day 1, reached the maximum at day 3 and then decreased to a plateau by day 15 after a single dose of carcinogen N-ethyl-N-nitrosourea (ENU) treatment, which is different from the longer mutation manifestation time and the constancy of MFs after reaching their maximum in some other tissues. To determine the mechanism underlying the quick increase in MF and the peak formation in the mutant manifestation, we examined the mutation frequencies and spectra of the ENU-induced mutants collected from different sampling times in this study. The cII mutants from days 1, 3 and 120 after ENU treatment were randomly selected from different animals. The mutation frequencies were 33, 217, 305 and 144 x 10(-6) for control, days 1, 3, and 120, respectively. The mutation spectra at days 1 and 3 were significantly different from that at day 120. Considering that stem cells are responsible for the ultimate MF plateau (day 120) and transit cells are accountable for the earlier MF induction (days 1 or 3) in mouse bone marrow, we conclude that transit cells are much more sensitive to mutation induction than stem cells in mouse bone marrow, which resulted in the specific mutation manifestation induced by ENU.

  10. Biomarkers for the early detection of cancer treatment induced cardiotoxicity

    NARCIS (Netherlands)

    Bulten, Ben

    2016-01-01

    In this thesis, the role of several imaging and nonimaging markers for the detection of anthracycline-induced and trastuzumab-induced cardiotoxicity (respectively AIC and TIC) is evaluated. Especially, the pathophysiology of these processes and the interrelationship of the various markers are

  11. Rice improvement through radiation-induced mutation for cultivation in South Vietnam

    International Nuclear Information System (INIS)

    Do Khac Thinh; Hung Phi Oanh; Nguyen Thi Cuc; Nguyen Ngoc Quynh

    2001-01-01

    For past years, rice varieties cultivated in South Vietnam originated from domestic hybridisation or from IRRI. Rice mutation breeding has been initiated for recent years. To meet the requirement of rice production diversification in different agro-ecological areas and rice genetic resources, from 1993 Institute of Agricultural Science of South Vietnam has carried out rice improvement by induced mutation of radiation. The mutagen was gamma rays of 60 Co. The goal is to create inherited variations, which cannot be obtained from other breeding methods, specially important characters of rice varieties (high tolerance to acid sulfate soil, lodging resistance combined with early maturity), which were difficult to gain by hybridisation. With 60 Co gamma rays, doses of 10-20 krad, dose rate of 280 krad/h, dry and germinated seeds of introduced and local rice varieties (IR 64, IR 9729, IR 50404, IR 59606, Jasmine 85, Nang Huong, Tam Xoan) were irradiated. The irradiated seeds were immediately sown within 24 and 94 hrs for wet seeds and dry seeds after treatment, respectively. Population of 10,000-15,000 plants were established and evaluated by IRRI evaluation standard from M2-M7 generations. 365 lines, varieties were selected with better behaviours than original varieties as lodging resistance, earliness, potential yield, leaf characters, tolerant ability to adverse conditions etc. Some good varieties (VND95-19, VND95-20) have been approved as leading national varieties and released for large-scale production in South Vietnam. (author)

  12. Ribosomal protein mutations induce autophagy through S6 kinase inhibition of the insulin pathway.

    Directory of Open Access Journals (Sweden)

    Harry F Heijnen

    Full Text Available Mutations affecting the ribosome lead to several diseases known as ribosomopathies, with phenotypes that include growth defects, cytopenia, and bone marrow failure. Diamond-Blackfan anemia (DBA, for example, is a pure red cell aplasia linked to the mutation of ribosomal protein (RP genes. Here we show the knock-down of the DBA-linked RPS19 gene induces the cellular self-digestion process of autophagy, a pathway critical for proper hematopoiesis. We also observe an increase of autophagy in cells derived from DBA patients, in CD34+ erythrocyte progenitor cells with RPS19 knock down, in the red blood cells of zebrafish embryos with RP-deficiency, and in cells from patients with Shwachman-Diamond syndrome (SDS. The loss of RPs in all these models results in a marked increase in S6 kinase phosphorylation that we find is triggered by an increase in reactive oxygen species (ROS. We show that this increase in S6 kinase phosphorylation inhibits the insulin pathway and AKT phosphorylation activity through a mechanism reminiscent of insulin resistance. While stimulating RP-deficient cells with insulin reduces autophagy, antioxidant treatment reduces S6 kinase phosphorylation, autophagy, and stabilization of the p53 tumor suppressor. Our data suggest that RP loss promotes the aberrant activation of both S6 kinase and p53 by increasing intracellular ROS levels. The deregulation of these signaling pathways is likely playing a major role in the pathophysiology of ribosomopathies.

  13. Study on mutation induced effect of gamma ray and DES on black bean phaseolus vulgaris

    Energy Technology Data Exchange (ETDEWEB)

    Le Thi Dinh; Pham Le Ha; Nguyen Van Toan; Le Xuan Tham [Nuclear Research Institute, Radiobiology Department, Dalat (Viet Nam)

    2001-03-01

    The study on mutation induced effect of gamma ray and DES on black bean Phaseolus vulgaris was carried out at Radiobiology Department, Nuclear Research Institute of Dalat. Dry seeds of variety No.1847 - Bonita - Cuba in set of 13 black bean varieties were irradiated with gamma ray from {sup 60}Co source at dose range from 150 Gy to 350 Gy and treated with DES at concentration from 0.1% to 0.3% in 2 hours for experiments in laboratory. The doses of 200, 250, 300 Gy and concentration of 0.2% DES in 2 hours were selected to treat dry seeds for experiments on the field. In populations of M{sub 1} generation, the height, number of branches and fruits per plant, number of seeds per fruit were decreased with increasing of irradiation doses. In populations of M{sub 2} generation, individual variants in leaf shape, chlorophyll, short stem, dwarf, early maturity, flowering in very short time were obtained and selected in all treatment cases. Mutation frequency at dose of 300 Gy was higher than that in other treatment cases, but ratio of sterility is also largest. The mutant lines of early maturity and short stem with flowering in very short time are promised materials for further studies. (author)

  14. Photoreactivation reverses ultraviolet radition induced premutagenic lesions leading to frameshift mutations in Escherichia coli

    International Nuclear Information System (INIS)

    Yamamoto, Kazuo

    1985-01-01

    The effect of photoreactivation of the ultraviolet radiation induced reversion of a trpE9777 frameshift mutation was studied in a uvr A6 derivative of Escherichia coli K12. Two different photoreactivation treatments were used, one providing a single flash of photoreactivating light and another providing 10 min of light from fluorescent lamps. The reversion frequency of the trpE9777 frameshift mutation was strongly reduced when subsueqently exposed to visible light. The dose modification factor (the ratio of equally effective doses), for cells challenged with single-flash photoreactivation, for survival and induction of reversion to Trp + was 3.6 and 3.4, respectively. UV induction of RecA protein synthesis was not reversed by a single flash of photoreactivation. The dose modification factor for 10 min of fluorescent lamp photoreactivation for survival and for induction of reversion to Trp + was 6.5 and 6.3, respectively. The dose modification factor for 10 min of photoreactivation for induction of RecA protein was 1.7-2.5. Photoreactivation decreased the reversion of trpE9777 and increased survival to the same extent. We concluded that cyclobutyl pyrimidine dimers are the premutagenic lesions of UV mutagenesis of the trpE9777 allele in a uvr A6 background. (orig.)

  15. Rice improvement through radiation-induced mutation for cultivation in South Vietnam

    Energy Technology Data Exchange (ETDEWEB)

    Do Khac Thinh; Hung Phi Oanh; Nguyen Thi Cuc; Nguyen Ngoc Quynh [Institute of Agricultural Science of South Vietnam, Ho Chi Minh (Viet Nam)

    2001-03-01

    For past years, rice varieties cultivated in South Vietnam originated from domestic hybridisation or from IRRI. Rice mutation breeding has been initiated for recent years. To meet the requirement of rice production diversification in different agro-ecological areas and rice genetic resources, from 1993 Institute of Agricultural Science of South Vietnam has carried out rice improvement by induced mutation of radiation. The mutagen was gamma rays of {sup 60}Co. The goal is to create inherited variations, which cannot be obtained from other breeding methods, specially important characters of rice varieties (high tolerance to acid sulfate soil, lodging resistance combined with early maturity), which were difficult to gain by hybridisation. With {sup 60}Co gamma rays, doses of 10-20 krad, dose rate of 280 krad/h, dry and germinated seeds of introduced and local rice varieties (IR 64, IR 9729, IR 50404, IR 59606, Jasmine 85, Nang Huong, Tam Xoan) were irradiated. The irradiated seeds were immediately sown within 24 and 94 hrs for wet seeds and dry seeds after treatment, respectively. Population of 10,000-15,000 plants were established and evaluated by IRRI evaluation standard from M2-M7 generations. 365 lines, varieties were selected with better behaviours than original varieties as lodging resistance, earliness, potential yield, leaf characters, tolerant ability to adverse conditions etc. Some good varieties (VND95-19, VND95-20) have been approved as leading national varieties and released for large-scale production in South Vietnam. (author)

  16. Tritiated uracil, tritiated thymidine, and bromodeoxyuridine induced mutations in eucaryotic cells

    International Nuclear Information System (INIS)

    Burki, H.J.; Moustacchi, E.; Cleaver, J.E.

    1979-02-01

    The induction of gene conversion at the ARG-4 locus in strain BZ34 of Saccharomyces cerevisiae was examined after the cells incorporated y- 3 H uracil under optimum growth conditions for 16 hours, and then received damage at 4 0 C from tritium decays at very low dose rates of 1.4 to 27.6 tritium decays per hour. The results were compared to the results of gene conversion induced by 60 Co. The induction of resistance to 6TG in Chinese hamster ovary (CHO) cells has been studied after incorporation of 3 H-methyl thymidine, 6- 3 H-thymidine, and bromodeoxyuridine under several experimental conditions. The induction of mutations by incorporated 6- 3 H-thymidine is about three times as effective as the induction of mutations by tritiated-methyl thymidine. These results suggest that the determination of the RBE for tritium decays in model eucaryotic systems like yeast and cultured Chinese hamster cells will be influenced by the precise experimental conditions employed. In particular, experiments with mammalian cells will be affected by hot times for mutagenesis in the cell cycle and hot positions within the DNA in the nucleus, and also by the position of tritium decay within the DNA-incorporated molecule

  17. A UV-induced mutation in neurospora that affects translational regulation in response to arginine

    International Nuclear Information System (INIS)

    Freitag, M.; Dighde, N.; Sachs, M.S.

    1996-01-01

    The Neurospora crassa arg-2 gene encodes the small subunit of arginine-specific carbamoyl phosphate synthetase. The levels of arg-2 mRNA and mRNA translation are negatively regulated by arginine. An upstream open reading frame (uORF) in the transcript's 5' region has been implicated in arginine-specific control. An arg-2-hph fusion gene encoding hygromycin phosphotransferase conferred arginine-regulated resistance to hygromycin when introduced into N. crassa. We used an arg-2-hph strain to select for UV-induced mutants that grew in the presence of hygromycin and arginine, and we isolated 46 mutants that had either of two phenotypes. One phenotype indicated altered expression of both arg-2-hph and arg-2 genes; the other, altered expression of arg-2-hph but not arg-2. One of the latter mutations, which was genetically closely linked to arg-2-hph, was recovered from the 5' region of the arg-2-hph gene using PCR Sequence analyses and transformation experiments revealed a mutation at uORF codon 12 (Asp to Asn) that abrogated negative regulation. Examination of the distribution of ribosomes on arg-2-hph transcripts showed that loss of regulation had a translational component, indicating the uORF sequence was important for Arg-specific translational control. Comparisons with other uORFs suggest common elements in translational control mechanisms

  18. Detection of low frequency FGFR3 mutations in the urine of bladder cancer patients using next-generation deep sequencing

    Directory of Open Access Journals (Sweden)

    Millholl

    2012-06-01

    Full Text Available John M Millholland, Shuqiang Li, Cecilia A Fernandez, Anthony P ShuberPredictive Biosciences Inc, Lexington, MA, USAAbstract: Biological fluid-based noninvasive biomarker assays for monitoring and diagnosing disease are clinically powerful. A major technical hurdle for developing these assays is the requirement of high analytical sensitivity so that biomarkers present at very low levels can be consistently detected. In the case of biological fluid-based cancer diagnostic assays, sensitivities similar to those of tissue-based assays are difficult to achieve with DNA markers due to the high abundance of normal DNA background present in the sample. Here we describe a new urine-based assay that uses ultradeep sequencing technology to detect single mutant molecules of fibroblast growth factor receptor 3 (FGFR3 DNA that are indicative of bladder cancer. Detection of FGFR3 mutations in urine would provide clinicians with a noninvasive means of diagnosing early-stage bladder cancer. The single-molecule assay detects FGFR3 mutant DNA when present at as low as 0.02% of total urine DNA and results in 91% concordance with the frequency that FGFR3 mutations are detected in bladder cancer tumors, significantly improving diagnostic performance. To our knowledge, this is the first practical application of next-generation sequencing technology for noninvasive cancer diagnostics.Keywords: FGFR3, mutation, urine, single molecule, sequencing, bladder cancer

  19. Study on the abnormalities in sperm and gene mutation induced by retention of 147Pm in testis

    International Nuclear Information System (INIS)

    Zhu Shoupeng; Lun Mingyue; Yang Shuqin

    1990-05-01

    The purpose of the present study is to ascertain 147 Pm retention in testis and its radiogenotoxicological effects of gene mutation through varying radioactivities of internal exposure. Especially the accumulation of 147 Pm in testis induces the dominant lethal, dominant skeletal mutation and abnormalities in sperm. Studies indicated that the cumulative absorption dose in testis increases as the internal exposure of 147 Pm increases. The internal exposure of 147 Pm can destroy the genetic materials and raise the rates of dominant lethal and dominant mutation of skeletal abnormalities in the offspring. The relationship between the rate of dominant skeletal mutation (B) and accumulated radioactivities of 147 Pm (D) in testis can be described by a linear equation that is B 20.68 + 35.48 D. The relationship between abnormalities of the sperm and the cumulative dose from 147 Pm in testis can be expressed by the following equation: S = 10.8705 D 0.5224 + 3.1768

  20. Next-Gen Sequencing-Based Mapping and Identification of Ethyl Methanesulfonate-Induced Mutations in Arabidopsis thaliana.

    Science.gov (United States)

    Zhang, Xue-Cheng; Millet, Yves; Ausubel, Frederick M; Borowsky, Mark

    2014-10-01

    Forward genetic analysis using ethyl methanesulfonate (EMS) mutagenesis has proven to be a powerful tool in biological research, but identification and cloning of causal mutations by conventional genetic mapping approaches is a painstaking process. Recent advances in next-gen sequencing have greatly invigorated the process of identifying EMS-induced mutations corresponding to a specific phenotype in model genetic hosts, including the plant Arabidopsis thaliana and the nematode Caenorhabditis elegans. Next-gen sequencing of bulked F2 mutant recombinants produces a wealth of high-resolution genetic data, provides enhanced delimitation of the genomic location of mutations, and greatly reduces hands-on time while maintaining high accuracy and reproducibility. In this unit, a detailed procedure to simultaneously map and identify EMS mutations in Arabidopsis is described. Copyright © 2014 John Wiley & Sons, Inc.

  1. Effect of 60-Hz magnetic fields on ultraviolet light-induced mutation and mitotic recombination in Saccharomyces cerevisiae.

    Science.gov (United States)

    Ager, D D; Radul, J A

    1992-12-01

    The purpose of this study was to examine the effect of extremely low frequency (ELF) magnetic fields on the induction of genetic damage. In general, mutational studies involving ELF magnetic fields have proven negative. However, studies examining sister-chromatid exchange and chromosome aberrations have yielded conflicting results. In this study, we have examined whether 60-Hz magnetic fields are capable of inducing mutation or mitotic recombination in the yeast Saccharomyces cerevisiae. In addition we determined whether magnetic fields were capable of altering the genetic response of S. cerevisiae to UV (254 nm). We measured the frequencies of induced mutation, gene conversion and reciprocal mitotic crossing-over for exposures to magnetic fields alone (1 mT) or in combination with various UV exposures (2-50 J/m2). These experiments were performed using a repair-proficient strain (RAD+), as well as a strain of yeast (rad3) which is incapable of excising UV-induced thymine dimers. Magnetic field exposures did not induce mutation, gene conversion or reciprocal mitotic crossing-over in either of these strains, nor did the fields influence the frequencies of UV-induced genetic events.

  2. The use of induced mutation combined with crossing in high quality rice breeding

    Energy Technology Data Exchange (ETDEWEB)

    Do Huu At; Bui Huy Thuy; Nguyen Van Bich; Tran Duy Quy [Agricultural Genetics Institute, Division of Genetics and Hybrid Rice Technology, Hanoi (Viet Nam); Nguyen Minh Cong [Hanoi No. 1 Teacher Training Univ., Department of Genetics (Viet Nam)

    2001-03-01

    The high quality rice varieties: Tam thom mutant rice Var., DT17 rice Var, DT21 glutinous rice Var were formed by induced mutation combined with crossing. Tam thom mutant rice Var. lost photosensitivity, could be planted 2 crops/year. DT17 rice Var with high yielding capacity, suitable for growth on lowland in summer crop, is replacing step-by-step Moctuyen rice Var. in North Vietnam. DT21 glutinous rice Var. could be planted 2 crops/year and had short growth duration, average yield was 4.0-4.5 tons/ha. These three ones had good quality, soft and scent cooked rice, suitable for customers and export requirements. Tam thom mutant rice Var. DT17 rice Var., DT21 and glutinous rice Var. were adopted for regional production by Ministry of Agriculture and Rural Development and allowed to be in trial production. (author)

  3. Induced Mutation on Jatropha (Jatropha Curcas L.) for Improvement of Agronomic Characters Variability

    International Nuclear Information System (INIS)

    Ita-Dwimahyani; Ishak

    2004-01-01

    Induced mutation can be used for improving quality in term of seed production, oil content in seed and early maturity of Jatropha with the aim for bio d iesel in Indonesia. The doses of 10, 15, 20, and 25 Gy of gamma applied to cuttings was able to increase genetic variability in vegetatively propagated plants of Jatropha at M1V1 (mutant-1 vegetative-1) generation. Selection for desirable trait will be done at M1V2 (mutant-1 and vegetative-2) generation until homogenous plants obtained. Gamma rays at dose of 20 to 25 Gy damaged several genes controlling growth and development on Jatropha which was shown by dwarf and poor plant growth compared to control (plant without irradiation). Irradiation with the dose of 10 Gy raised genetic variability on plant development which was identified with early maturity. 100 seeds weight was 30% over control, and the number of branch growth was good. (author)

  4. Primary Ovarian Insufficiency Induced by Fanconi Anemia E Mutation in a Mouse Model.

    Science.gov (United States)

    Fu, Chun; Begum, Khurshida; Overbeek, Paul A

    2016-01-01

    In most cases of primary ovarian insufficiency (POI), the cause of the depletion of ovarian follicles is unknown. Fanconi anemia (FA) proteins are known to play important roles in follicular development. Using random insertional mutagenesis with a lentiviral transgene, we identified a family with reduced fertility in the homozygous transgenic mice. We identified the integration site and found that the lentivirus had integrated into intron 8 of the Fanconi E gene (Fance). By RT-PCR and in situ hybridization, we found that Fance transcript levels were significantly reduced. The Fance homozygous mutant mice were assayed for changes in ovarian development, follicle numbers and estrous cycle. Ovarian dysplasias and a severe lack of follicles were seen in the mutant mice. In addition, the estrous cycle was disrupted in adult females. Our results suggest that POI has been induced by the Fance mutation in this new mouse model.

  5. The use of induced mutation combined with crossing in high quality rice breeding

    International Nuclear Information System (INIS)

    Do Huu At; Bui Huy Thuy; Nguyen Van Bich; Tran Duy Quy; Nguyen Minh Cong

    2001-01-01

    The high quality rice varieties: Tam thom mutant rice Var., DT17 rice Var, DT21 glutinous rice Var were formed by induced mutation combined with crossing. Tam thom mutant rice Var. lost photosensitivity, could be planted 2 crops/year. DT17 rice Var with high yielding capacity, suitable for growth on lowland in summer crop, is replacing step-by-step Moctuyen rice Var. in North Vietnam. DT21 glutinous rice Var. could be planted 2 crops/year and had short growth duration, average yield was 4.0-4.5 tons/ha. These three ones had good quality, soft and scent cooked rice, suitable for customers and export requirements. Tam thom mutant rice Var. DT17 rice Var., DT21 and glutinous rice Var. were adopted for regional production by Ministry of Agriculture and Rural Development and allowed to be in trial production. (author)

  6. Effect of uvs1, uvs2 and xrs mutations on the radiosensitivity and the induced mitotic recombination frequency in diploid yeast cells

    International Nuclear Information System (INIS)

    Suslova, N.G.; Fedorova, I.V.; Zheleznyakova, N.Yu.

    1975-01-01

    The influence of the loci of radiosensitivity uvs1, uvs2, and xrs in the homozygous state at the diploid level on the sensitivity to UV and ionizing radiation and induced mitotic recombination was studied in the yeast Sacch. cerevisiae. Hypersensitivity to UV irradiation was detected in the diploids uvs2 uvs2 xrs xrs in comparision with the corresponding control. The diploid uvs1 uvs1 uvs2 uvs2 does not differ in UV sensitivity from the diploid uvs1 uvs1 UVS2 UVS2. These facts demonstrate that the uvs1 and uvs2 mutations, on the one hand, and the xrs mutations, on the other, normally control different pathways of elimination of UV-induced damages. It was shown that the diploid uvs2 uvs2 xrs3 xrs3 is far more sensitive to the lethal action of x rays than the control diploid UVS2 UVS2 xrs3 xrs3. Consequently, the mutations uvs2 and xrs3 block different modes of repair of damages induced by ionizing radiation. In all the double-mutant diploids, the frequency of mitotic recombination induced by UV rays increases sharply in comparison with that of the radioresistant diploids UVS UVS XRS XRS and the UV-sensitive diploids uvs2 uvs2 XRS XRS. Possible causes of the observed phenomenon are discussed. It was established that in a diploid homozygous for the loci uvs2 xrs5, the frequency of mitotic recombination induced by x rays increases extremely sharply. This fact confirms the hypothesis that the gene product of the locus uvs2 participates in the repair of DNA after the action of ionizing radiation. (author)

  7. Significance of combined detection of JAK2V617F, MPL and CALR gene mutations in patients with essential thrombocythemia.

    Science.gov (United States)

    Ji, Liying; Qian, Mengyao; Wu, Nana; Wu, Jianmin

    2017-03-01

    The aim of this study was to analyze the mutation rate of JAK2V617F, MPLW515L/K and CALR genes in adult patients with essential thrombocythemia (ET) and the accuracy of the combined detection by the receiver operating curve. Three hundred and forty-two cases with high-platelets (≥300×10 9 /l) were consecutively selected. The patients were analyzed for routine blood examination, bone marrow biopsy and genetic testing. One hundred and fifty-four cases (45.03%) were diagnosed with ET and 188 cases of secondary thrombocythemia according to the hematopoietic and lymphoid tissue tumor classification standards of 2008. It was found that the mutant type of three genes showed three bands, whereas only one band for wild-type. The JAK2V617F and MPL mutations did not cause a change in the open reading frame and the CALR mutation resulted in its change. The mutation rate of JAK2V617F and CALR in ET group was significantly higher than that in the secondary thrombocythemia group (p<0.05). The positive mutation rate of MPL was only 4.55%. JAK2V617F-positive mutation alone was used to diagnose with ET. The area under the curve (AUC) was 0.721. The sensitivity was 72.4%, the specificity was 79.5% and the cut-off value was 0.25. When CALR-positive mutation alone was used to diagnose ET, the AUC, sensitivity, specificity and cut-off value were 0.664, 68.4, 82.4 and 0.09%, respectively. JAK2V617F combined with CALR mutation were used for diagnosis of ET. The AUC was 0.862, the sensitivity was 85.9%, the specificity was 87.8%, and the cut-off values were 0.21 and 0.07. In conclusion, the positive mutation rate of JAK2V617F and CALR in ET was higher, and the sensitivity, specificity and accuracy of the diagnosis of ET were significantly improved using the detection of JAK2V617F and CALR.

  8. Characterization of Cat-2t, a radiation-induced dominant cataract mutation in mice

    International Nuclear Information System (INIS)

    Graw, J.; Bors, W.; Gopinath, P.M.; Merkle, S.; Michel, C.; Reitmeir, P.; Schaeffer, E.S.; Summer, K.H.; Wulff, A.

    1990-01-01

    A dominant cataract mutation was detected recently among the offspring of x-ray-irradiated male mice. The mutation, which causes total lens opacity, has provisionally been designated by the gene symbol Cat-2t. In the lenses of heterozygous and homozygous Cat-2t mutants, the epithelial and fiber cells were swollen and the lens capsule was ruptured. The histologic analysis demonstrated a complete destruction of the cellular organization of the lens, which might be caused by its altered developmental processes. The data derived from biochemical investigations indicate that biochemistry of the cataractous Cat-2t lenses is affected: the osmotic state as indicated by the increased water content and increased Na(+)-K(+)-adenosinetriphosphatase (ATPase) activity; the energy state as indicated by the decreased adenosine triphosphate (ATP) concentration; and the redox state as indicated by the enhanced content of oxidized glutathione. Additionally, the lenticular protein composition is altered because of the presence of vimentin in the water-soluble fraction. This cannot be explained by the enhanced crosslinking activity of transglutaminase. The changes of the osmotic, energy, and redox states are considered to be secondary in relation to the altered lenticular development. In contrast, the variations concerning vimentin and transglutaminase might be a biochemical indication of the changed development. Possible similarities to other dominantly expressed murine cataract mutants are discussed

  9. Chemotherapy-induced amenorrhea in patients with breast cancer with a BRCA1 or BRCA2 mutation.

    Science.gov (United States)

    Valentini, Adriana; Finch, Amy; Lubinski, Jan; Byrski, Tomasz; Ghadirian, Parviz; Kim-Sing, Charmaine; Lynch, Henry T; Ainsworth, Peter J; Neuhausen, Susan L; Greenblatt, Ellen; Singer, Christian; Sun, Ping; Narod, Steven A

    2013-11-01

    To determine the likelihood of long-term amenorrhea after treatment with chemotherapy in women with breast cancer who carry a BRCA1 or BRCA2 mutation. We conducted a multicenter survey of 1,954 young women with a BRCA1 or BRCA2 mutation who were treated for breast cancer. We included premenopausal women who were diagnosed with invasive breast cancer between 26 and 47 years of age. We determined the age of onset of amenorrhea after breast cancer for women who were and were not treated with chemotherapy, alone or with tamoxifen. We considered chemotherapy-induced amenorrhea to have occurred when the patient experienced ≥ 2 years of amenorrhea, commencing within 2 years of initiating chemotherapy, with no resumption of menses. Of the 1,426 women who received chemotherapy, 35% experienced long-term amenorrhea. Of the 528 women who did not receive chemotherapy, 5.3% developed long-term amenorrhea. The probabilities of chemotherapy-induced amenorrhea were 7.2% for women diagnosed before age 30 years, 33% for women age 31 to 44 years, and 79% for women diagnosed after age 45 years (P trend amenorrhea was higher for women who received tamoxifen than for those who did not (52% v 29%; P amenorrhea in women who carry a BRCA1 or BRCA2 mutation. The risk of induced long-term amenorrhea does not seem to be greater among mutation carriers than among women who do not carry a mutation.

  10. Embryonic left-right separation mechanism allows confinement of mutation-induced phenotypes to one lateral body half of bilaterians.

    Science.gov (United States)

    Ma, Kun

    2013-12-01

    A fundamental question in developmental biology is how a chimeric animal such as a bilateral gynandromorphic animal can have different phenotypes confined to different lateral body halves, and how mutation-induced phenotypes, such as genetic diseases, can be confined to one lateral body half in patients. Here, I propose that embryos of many, if not all, bilaterian animals are divided into left and right halves at a very early stage (which may vary among different types of animals), after which the descendants of the left-sided and right-sided cells will almost exclusively remain on their original sides, respectively, throughout the remaining development. This embryonic left-right separation mechanism allows (1) mutations and the mutation-induced phenotypes to be strictly confined to one lateral body half in animals and humans; (2) mothers with bilateral hereditary primary breast cancer to transmit their disease to their offspring at twofold of the rate compared to mothers with unilateral hereditary breast cancer; and (3) a mosaic embryo carrying genetic or epigenetic mutations to develop into either an individual with the mutation-induced phenotype confined unilaterally, or a pair of twins displaying complete, partial, or mirror-image discordance for the phenotype. Further, this left-right separation mechanism predicts that the two lateral halves of a patient carrying a unilateral genetic disease can each serve as a case and an internal control, respectively, for genetic and epigenetic comparative studies to identify the disease causations. © 2013 Wiley Periodicals, Inc.

  11. Fifteen novel FBN1 mutations causing Marfan syndrome detected by heteroduplex analysis of genomic amplicons

    Energy Technology Data Exchange (ETDEWEB)

    Nijbroek, G.; Sood, S.; McIntosh, I. [John Hopkins Univ. School of Medicine, Baltimore, MD (United States)] [and others

    1995-07-01

    Mutations in the gene encoding fibrillin-1 (FBN1), a component of the extracellular microfibril, cause the Marfan syndrome (MFS). This statement is supported by the observations that the classic Marfan phenotype cosegregates with intragenic and/or flanking marker alleles in all families tested and that a significant number of FBN1 mutations have been identified in affected individuals. We have now devised a method to screen the entire coding sequence and flanking splice junctions of FBN1. On completion for a panel of nine probands with classic MFS, six new mutations were identified that accounted for disease in seven (78%) of nine patients. Nine additional new mutations have been characterized in the early stages of a larger screening project. These 15 mutations were equally distributed throughout the gene and, with one exception, were specific to single families. One-third of mutations created premature termination codons, and 6 of 15 substituted residues with putative significance for calcium finding to epidermal growth factor (EGF)-like domains. Mutations causing severe and rapidly progressive disease that presents in the neonatal period can occur in a larger region of the gene than previously demonstrated, and the nature of the mutation is as important a determinant as its location, in predisposing to this phenotype. 56 refs., 5 figs., 3 tabs.

  12. Detection of non-ΔGT NCF-1 mutations in chronic granulomatous disease

    DEFF Research Database (Denmark)

    Jakobsen, Marianne Antonius; Pedersen, Svend Stenvang; Barington, Torben

    2009-01-01

    to have mutations in NCF-1 encoding p47-phox, which is part of the cytosolic component of NADPH oxidase. More than 94% of these patients share the same mutation, a 2 bp GT deletion in the GTGT dinucleotide repeat in the start of exon 2. The presence of two pseudogenes more than 98% homologous...

  13. Methylmethane-sulphonate and X-ray-induced mutations in the Chinese hamster hprt gene: mRNA phenotyping using polymerase chain reactions

    International Nuclear Information System (INIS)

    Chaudhry, M.A.; Fox, Margaret

    1990-01-01

    Alterations in the hprt gene of Chinese hamster cells were determined in 71 spontaneous, methylmethane sulphonate (MMS)-and X-ray induced mutants, using the Southern blot hybridization technique. To investigate the possibility of small deletions, MMS-induced mutants were studied with proves derived from exons 3 and 9 but no evidence of specific deletion of these two exons was found. The polymerase chain reaction (PCR) was used to phenotype hprt transcripts in 48 MMS, X-ray and spontaneous Chinese hamster mutants by amplifying the coding region of their cDNA. Among 22 MMS-induced mutants the message was present in 16 instances. An analysis of 20 X-ray-induced mutants showed the presence of hprt mRNA in 11 of them with five having low levels of transcription. Among six spontaneous mutants, four were negative for mRNA on standard Northern blots and in one the message was only detected after PCR amplification. Direct DNA sequencing of 10 mutants revealed the presence of base substitutions in five of them while a 7 bp deletion was found in another. No mutations were found in another four mutants, suggesting the presence of mutation outside the coding region. (author)

  14. Improvement of new and traditional industrial crops by induced mutations and related biotechnology

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-08-01

    Industrial crops are an important source of income for many small landholders in developing countries and contribute directly or indirectly to food security in rural areas. Crop diversification, finding alternative crops, development of new uses for existing crops and introduction of new crops are important components in the efforts to meet the demand for food, pharmaceuticals, chemical raw materials, fibres and fuel in developing and developed countries. Plant breeding efforts combining genetic resources and induced mutations using classical, in vitro and innovative molecular approaches have been responsible for much of the development of industrial crops. This co-ordinated research project (CRP) was initiated in 1994. It focused on developing mutagenesis approaches for previously unstudied species, screening procedures for agricultural and industrial requirements and suitable genotypes of traditional industrial crops adapted to new areas and for new needs. The industrial crops selected for improvement under this CRP were oilseeds and fibre plants. The potential of induced mutations to affect critical steps in various biosynthetic pathways leading to oil quality and other metabolic modifications was investigated. The success of this CRP is evidenced by the application of mutation techniques, in combination with in vitro and molecular techniques in genetic improvement of oilseed crops such as soybean, rapeseed, sunflower, linseed, cuphea, meadowfoam and fibre plants such as cotton and jute. As a result, improved breeding lines are available in all the industrial crops that the CRP focused on. Novel oil types were developed in cuphea with potential use as a renewable, economical and safe energy source and in linseed with increased levels of saturated fatty acids. Genes of fatty acid synthesis were isolated from one species and used for modification of quality of other oilseeds. Disease and pest resistance was improved in oilseeds and fibre crops through transgenesis

  15. Improvement of new and traditional industrial crops by induced mutations and related biotechnology

    International Nuclear Information System (INIS)

    2003-08-01

    Industrial crops are an important source of income for many small landholders in developing countries and contribute directly or indirectly to food security in rural areas. Crop diversification, finding alternative crops, development of new uses for existing crops and introduction of new crops are important components in the efforts to meet the demand for food, pharmaceuticals, chemical raw materials, fibres and fuel in developing and developed countries. Plant breeding efforts combining genetic resources and induced mutations using classical, in vitro and innovative molecular approaches have been responsible for much of the development of industrial crops. This co-ordinated research project (CRP) was initiated in 1994. It focused on developing mutagenesis approaches for previously unstudied species, screening procedures for agricultural and industrial requirements and suitable genotypes of traditional industrial crops adapted to new areas and for new needs. The industrial crops selected for improvement under this CRP were oilseeds and fibre plants. The potential of induced mutations to affect critical steps in various biosynthetic pathways leading to oil quality and other metabolic modifications was investigated. The success of this CRP is evidenced by the application of mutation techniques, in combination with in vitro and molecular techniques in genetic improvement of oilseed crops such as soybean, rapeseed, sunflower, linseed, cuphea, meadowfoam and fibre plants such as cotton and jute. As a result, improved breeding lines are available in all the industrial crops that the CRP focused on. Novel oil types were developed in cuphea with potential use as a renewable, economical and safe energy source and in linseed with increased levels of saturated fatty acids. Genes of fatty acid synthesis were isolated from one species and used for modification of quality of other oilseeds. Disease and pest resistance was improved in oilseeds and fibre crops through transgenesis

  16. Modifying effect of 5-fluoro-2-deoxiuridine on the frequency of x-ray-induced visible mutations in wheat

    International Nuclear Information System (INIS)

    Azatyan, R.A.; Avakyan, V.A.

    1985-01-01

    A modifying effect of FUDR on the output of visible mutations induced by X-ray radiation has been studied at soft fall wheat (Tr. aestivum var. turcicum). It is shown that at X-ray radiation of dry seeds with subsequent treatment of FUDR increased is the mutant percent in M 3 which has constituted 0.61% at irradiation in dose of 100 Gy ad 1.03% at irradiation by the same dose and FUDR influence during 10 hours. In analogous variants at irradiation by 150 Gi dose the mutation frequency reached 1.47 and 2.07% respectively. It is shown that FUDR postradiation treatment promotes not only the increase of frequency but consderablly widens the spectrum of induced mutations. A supposition is made that FUDR modyfying effect is caused by DNA synthesis inhibition. A problem is discussed on a possible realization of potential DNA changes caused by irradiation, at additional influence of inhibitor

  17. RAPID DETECTION OF -THALASSEMIA MUTATIONS IN THAILAND USING MULTIPLEX ARMS

    Directory of Open Access Journals (Sweden)

    D. Shimbhu

    2017-11-01

    Full Text Available The number of mutations underlining b-thalassemia generate a wide variety of different clinical phenotypes. An understanding of the genotype is important for medical personnel in order to provide proper counseling to patients and their families. Characterization of these mutations should aid the planning of a prenatal diagnosis program for bthalassemia. The heterogeneity of the mutations makes it difficult and time consuming to identify the mutation in some individuals. We developed a single-tube multiplex amplification refractory mutation system (multiplex ARMS to identify common ethnic- specific b-thalassemia mutations. Confirmation of multiplex ARMS results was carried out using direct sequencing. Three thousand three hundred twenty two people from Phitsanulok province were screened for the b-thalassemia trait by quantitation of HbA2 with microcolumn chromatography and the genotypes of mutations were characterized using multiplex ARMS and direct sequencing. We found that the deletion at codons 41/42 (-TCTT was the most frequent (48%, codon 17 (A®T (30%, -28 (A®G (6% and IVS-I-1(G®T (6% were the second and third in frequency respectively. A -87 (C®A mutation (4%, IVS II-654 (C®T (2%, codons 71/72 (+A (2% and codon 35 (C®A mutations (2% were also found. These techniques were found to be a valuable tool for analysis of b-thalassemia mutations because they are accurate, simple, and speedy in operation. The application for the diagnosis of severe thalassemia in high-risk pregnancies is promising.

  18. Rapid and Simple Detection of Hot Spot Point Mutations of Epidermal Growth Factor Receptor, BRAF, and NRAS in Cancers Using the Loop-Hybrid Mobility Shift Assay

    Science.gov (United States)

    Matsukuma, Shoichi; Yoshihara, Mitsuyo; Kasai, Fumio; Kato, Akinori; Yoshida, Akira; Akaike, Makoto; Kobayashi, Osamu; Nakayama, Haruhiko; Sakuma, Yuji; Yoshida, Tsutomu; Kameda, Yoichi; Tsuchiya, Eiju; Miyagi, Yohei

    2006-01-01

    A simple and rapid method to detect the epidermal growth factor receptor hot spot mutation L858R in lung adenocarcinoma was developed based on principles similar to the universal heteroduplex generator technology. A single-stranded oligonucleotide with an internal deletion was used to generate heteroduplexes (loop-hybrids) bearing a loop in the complementary strand derived from the polymerase chain reaction product of the normal or mutant allele. By placing deletion in the oligonucleotide adjacent to the mutational site, difference in electrophoretic mobility between loop-hybrids with normal and mutated DNA was distinguishable in a native polyacrylamide gel. The method was also modified to detect in-frame deletion mutations of epidermal growth factor receptor in lung adenocarcinomas. In addition, the method was adapted to detect hot spot mutations in the B-type Raf kinase (BRAF) at V600 and in a Ras-oncogene (NRAS) at Q61, the mutations commonly found in thyroid carcinomas. Our mutation detection system, designated the loop-hybrid mobility shift assay was sensitive enough to detect mutant DNA comprising 7.5% of the total DNA. As a simple and straightforward mutation detection technique, loop-hybrid mobility shift assay may be useful for the molecular diagnosis of certain types of clinical cancers. Other applications are also discussed. PMID:16931592

  19. Droplet digital PCR-based EGFR mutation detection with an internal quality control index to determine the quality of DNA.

    Science.gov (United States)

    Kim, Sung-Su; Choi, Hyun-Jeung; Kim, Jin Ju; Kim, M Sun; Lee, In-Seon; Byun, Bohyun; Jia, Lina; Oh, Myung Ryurl; Moon, Youngho; Park, Sarah; Choi, Joon-Seok; Chae, Seoung Wan; Nam, Byung-Ho; Kim, Jin-Soo; Kim, Jihun; Min, Byung Soh; Lee, Jae Seok; Won, Jae-Kyung; Cho, Soo Youn; Choi, Yoon-La; Shin, Young Kee

    2018-01-11

    In clinical translational research and molecular in vitro diagnostics, a major challenge in the detection of genetic mutations is overcoming artefactual results caused by the low-quality of formalin-fixed paraffin-embedded tissue (FFPET)-derived DNA (FFPET-DNA). Here, we propose the use of an 'internal quality control (iQC) index' as a criterion for judging the minimum quality of DNA for PCR-based analyses. In a pre-clinical study comparing the results from droplet digital PCR-based EGFR mutation test (ddEGFR test) and qPCR-based EGFR mutation test (cobas EGFR test), iQC index ≥ 0.5 (iQC copies ≥ 500, using 3.3 ng of FFPET-DNA [1,000 genome equivalents]) was established, indicating that more than half of the input DNA was amplifiable. Using this criterion, we conducted a retrospective comparative clinical study of the ddEGFR and cobas EGFR tests for the detection of EGFR mutations in non-small cell lung cancer (NSCLC) FFPET-DNA samples. Compared with the cobas EGFR test, the ddEGFR test exhibited superior analytical performance and equivalent or higher clinical performance. Furthermore, iQC index is a reliable indicator of the quality of FFPET-DNA and could be used to prevent incorrect diagnoses arising from low-quality samples.

  20. NanoTIO2 (UV-Titan) does not induce ESTR mutations in the germline of prenatally exposed female mice

    DEFF Research Database (Denmark)

    Boisen, Anne Mette Zenner; Shipley, Thomas; Hougaard, Karin Sørig

    2012-01-01

    Particulate air pollution has been linked to an increased risk of cardiovascular disease and cancer. Animal studies have shown that inhalation of air particulates induces mutations in the male germline. Expanded simple tandem repeat (ESTR) loci in mice are sensitive markers of mutagenic effects o...

  1. Absence of p53 gene mutations in mice colon pre-cancerous stage induced by o-nitrotoluene

    Directory of Open Access Journals (Sweden)

    Nahed A Hussien

    2014-01-01

    Conclusion: The results from the present study indicate that point mutations in the p53 gene, in the coding region (exons 5-8 and outside it (exons 10, 11, are not involved in the development of the colon precancerous stage induced by o-nt in mice.

  2. High-resolution melting (HRM) assay for the detection of recurrent BRCA1/BRCA2 germline mutations in Tunisian breast/ovarian cancer families.

    Science.gov (United States)

    Riahi, Aouatef; Kharrat, Maher; Lariani, Imen; Chaabouni-Bouhamed, Habiba

    2014-12-01

    Germline deleterious mutations in the BRCA1/BRCA2 genes are associated with an increased risk for the development of breast and ovarian cancer. Given the large size of these genes the detection of such mutations represents a considerable technical challenge. Therefore, the development of cost-effective and rapid methods to identify these mutations became a necessity. High resolution melting analysis (HRM) is a rapid and efficient technique extensively employed as high-throughput mutation scanning method. The purpose of our study was to assess the specificity and sensitivity of HRM for BRCA1 and BRCA2 genes scanning. As a first step we estimate the ability of HRM for detection mutations in a set of 21 heterozygous samples harboring 8 different known BRCA1/BRCA2 variations, all samples had been preliminarily investigated by direct sequencing, and then we performed a blinded analysis by HRM in a set of 68 further sporadic samples of unknown genotype. All tested heterozygous BRCA1/BRCA2 variants were easily identified. However the HRM assay revealed further alteration that we initially had not searched (one unclassified variant). Furthermore, sequencing confirmed all the HRM detected mutations in the set of unknown samples, including homozygous changes, indicating that in this cohort, with the optimized assays, the mutations detections sensitivity and specificity were 100 %. HRM is a simple, rapid and efficient scanning method for known and unknown BRCA1/BRCA2 germline mutations. Consequently the method will allow for the economical screening of recurrent mutations in Tunisian population.

  3. Homozygosity mapping in autosomal recessive retinitis pigmentosa families detects novel mutations

    Science.gov (United States)

    Marzouka, Nour al Dain; Hebrard, Maxime; Manes, Gaël; Sénéchal, Audrey; Meunier, Isabelle; Hamel, Christian P.

    2013-01-01

    Purpose Autosomal recessive retinitis pigmentosa (arRP) is a genetically heterogeneous disease resulting in progressive loss of photoreceptors that leads to blindness. To date, 36 genes are known to cause arRP, rendering the molecular diagnosis a challenge. The aim of this study was to use homozygosity mapping to identify the causative mutation in a series of inbred families with arRP. Methods arRP patients underwent standard ophthalmic examination, Goldman perimetry, fundus examination, retinal OCT, autofluorescence measurement, and full-field electroretinogram. Fifteen consanguineous families with arRP excluded for USH2A and EYS were genotyped on 250 K SNP arrays. Homozygous regions were listed, and known genes within these regions were PCR sequenced. Familial segregation and mutation analyzes were performed. Results We found ten mutations, seven of which were novel mutations in eight known genes, including RP1, IMPG2, NR2E3, PDE6A, PDE6B, RLBP1, CNGB1, and C2ORF71, in ten out of 15 families. The patients carrying RP1, C2ORF71, and IMPG2 mutations presented with severe RP, while those with PDE6A, PDE6B, and CNGB1 mutations were less severely affected. The five families without mutations in known genes could be a source of identification of novel genes. Conclusions Homozygosity mapping combined with systematic screening of known genes results in a positive molecular diagnosis in 66.7% of families. PMID:24339724

  4. Detection of Deafness-Causing Mutations in the Greek Mitochondrial Genome

    Directory of Open Access Journals (Sweden)

    Haris Kokotas

    2011-01-01

    Full Text Available Mitochondrion harbors its own DNA, known as mtDNA, encoding certain essential components of the mitochondrial respiratory chain and protein synthesis apparatus. mtDNA mutations have an impact on cellular ATP production and many of them are undoubtedly a factor that contributes to sensorineural deafness, including both syndromic and non-syndromic forms. Hot spot regions for deafness mutations are the MTRNR1 gene, encoding the 12S rRNA, the MTTS1 gene, encoding the tRNA for Ser(UCN, and the MTTL1 gene, encoding the tRNA for Leu(UUR. We investigated the impact of mtDNA mutations in the Greek hearing impaired population, by testing a cohort of 513 patients suffering from childhood onset prelingual or postlingual, bilateral, sensorineural, syndromic or non-syndromic hearing loss of any degree for six mitochondrial variants previously associated with deafness. Screening involved the MTRNR1 961delT/insC and A1555G mutations, the MTTL1 A3243G mutation, and the MTTS1 A7445G, 7472insC and T7510C mutations. Although two patients were tested positive for the A1555G mutation, we failed to identify any subject carrying the 961delT/insC, A3243G, A7445G, 7472insC, or T7510C mutations. Our findings strongly support our previously raised conclusion that mtDNA mutations are not a major risk factor for sensorineural deafness in the Greek population.

  5. New Real-Time PCR Assays for Detection of Inducible and Acquired Clarithromycin Resistance in the Mycobacterium abscessus Group.

    Science.gov (United States)

    Shallom, Shamira J; Moura, Natalia S; Olivier, Kenneth N; Sampaio, Elizabeth P; Holland, Steven M; Zelazny, Adrian M

    2015-11-01

    Members of the Mycobacterium abscessus group (MAG) cause lung, soft tissue, and disseminated infections. The oral macrolides clarithromycin and azithromycin are commonly used for treatment. MAG can display clarithromycin resistance through the inducible erm(41) gene or via acquired mutations in the rrl (23S rRNA) gene. Strains harboring a truncation or a T28C substitution in erm(41) lose the inducible resistance trait. Phenotypic detection of clarithromycin resistance requires extended incubation (14 days), highlighting the need for faster methods to detect resistance. Two real-time PCR-based assays were developed to assess inducible and acquired clarithromycin resistance and tested on a total of 90 clinical and reference strains. A SYBR green assay was designed to distinguish between a full-length and truncated erm(41) gene by temperature shift in melting curve analysis. Single nucleotide polymorphism (SNP) allele discrimination assays were developed to distinguish T or C at position 28 of erm(41) and 23S rRNA rrl gene mutations at position 2058 and/or 2059. Truncated and full-size erm(41) genes were detected in 21/90 and 69/90 strains, respectively, with 64/69 displaying T at nucleotide position 28 and 5/69 containing C at that position. Fifteen isolates showed rrl mutations conferring clarithromycin resistance, including A2058G (11 isolates), A2058C (3 isolates), and A2059G (1 isolate). Targeted sequencing and phenotypic assessment of resistance concurred with molecular assay results. Interestingly, we also noted cooccurring strains harboring an active erm(41), inactive erm(41), and/or acquired mutational resistance, as well as slowly growing MAG strains and also strains displaying an inducible resistance phenotype within 5 days, long before the recommended 14-day extended incubation. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  6. Application of PCR-LDR-nucleic acid detection strip in detection of YMDD mutation in hepatitis B patients treated with lamivudine.

    Science.gov (United States)

    Xu, Gaolian; You, Qimin; Pickerill, Sam; Zhong, Huayan; Wang, Hongying; Shi, Jian; Luo, Ying; You, Paul; Kong, Huimin; Lu, Fengmin; Hu, Lin

    2010-07-01

    Chronic hepatitis B virus (CHBV) infection causes cirrhosis and hepatocellular carcinoma. Lamivudine (LAM) has been successfully used to treat CHBV infections but prolonged use leads to the emergence of drug-resistant variants. This is primarily linked to a mutation in the tyrosine-methionine-aspartate-aspartate (YMDD) motif of the HBV polymerase gene at position 204. Rapid diagnosis of drug-resistant HBV is necessary for a prompt treatment response. Common diagnostic methods such as sequencing and restriction fragment length polymorphism (RFLP) analysis lack sensitivity and require significant processing. The aim of this study was to demonstrate the usefulness of a novel diagnostic method that combines polymerase chain reaction (PCR), ligase detection reaction (LDR) and a nucleic acid detection strip (NADS) in detecting site-specific mutations related to HBV LAM resistance. We compared this method (PLNA) to direct sequencing and RFLP analysis in 50 clinical samples from HBV infected patients. There was 90% concordance between all three results. PLNA detected more samples containing mutant variants than both sequencing and RFLP analysis and was more sensitive in detecting mixed variant populations. Plasmid standards indicated that the sensitivity of PLNA is at or below 3,000 copies per ml and that it can detect a minor variant at 5% of the total viral population. This warrants its further development and suggests that the PLNA method could be a useful tool in detecting LAM resistance. (c) 2010 Wiley-Liss, Inc.

  7. Laboratory practice guidelines for detecting and reporting JAK2 and MPL mutations in myeloproliferative neoplasms: a report of the Association for Molecular Pathology.

    Science.gov (United States)

    Gong, Jerald Z; Cook, James R; Greiner, Timothy C; Hedvat, Cyrus; Hill, Charles E; Lim, Megan S; Longtine, Janina A; Sabath, Daniel; Wang, Y Lynn

    2013-11-01

    Recurrent mutations in JAK2 and MPL genes are genetic hallmarks of BCR-ABL1-negative myeloproliferative neoplasms. Detection of JAK2 and MPL mutations has been incorporated into routine diagnostic algorithms for these diseases. This Special Article summarizes results from a nationwide laboratory survey of JAK2 and MPL mutation analysis. Based on the current practice pattern and the literature, this Special Article provides recommendations and guidelines for laboratory practice for detection of mutations in the JAK2 and MPL genes, including clinical manifestations for prompting the mutation analysis, current and recommended methodologies for testing the mutations, and standardization for reporting the test results. This Special Article also points to future directions for genomic testing in BCR-ABL1-negative myeloproliferative neoplasms. Copyright © 2013 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

  8. Breeding sesame for diseases and shatter resistant high yielding varieties with induced mutations

    International Nuclear Information System (INIS)

    Kang, C.W.

    2001-01-01

    ''Suwon 144'', derived from the cross between ''Danbaeckkae'' and mutant MY-74-2 and in spite of its higher yield and quality compared to the check variety, did not pass the nomination to the Committee of Main Crops New Varieties under the Ministry of Agriculture and Forestry, due to the decision of the committee to limit the number of new varieties in sesame as a minor crop in Korea. ''Suwon 144'' will be released again for a fifth year to RYT in 1998. 5,282 cross combinations and 4,341 lines including 1,388 crossings of F 1 were crossed and released to the experimental field of NCES in 1997. Mutants and their cross combinations were released and constituted more than half among them. Seeds of ''Suwon 152'' were treated with NaN 3 and tested for germinability. The other seeds were released and harvested in the experimental field and 419 mutant lines were selected among all the mutant lines. Mutants or materials from cross breeding with mutants occupied 71% (675) among a total of 952 promising lines in yield trials of OYT, PYT, AYT and RYT. For variability of NaN 3 induced genetic male sterile (GMS) mutants and development of restorer/s of GMS, GMS lines were planted, and male sterility (MS) expression evaluated on each line. The selected 4 MS lines with 50% MS were crossed in 22 combinations with 7 recommended varieties. For development of genic-cytoplasmic MS (GCMS) using NaN 3 induced GMS mutants, 40 recommended local Korean and introduced cultivars were crossed in 57 combinations with 4 selected GMS lines expressing 50% male sterility. Various and many sources of unique characteristics have been continuously created through induced mutations, such as determinate; dwarf, lodging,- Phytophthora blight- and shatter- resistant; indehiscent, seamless, taller, stronger thick stems, dense capsule bearing type, semi-dwarf, better maturity, male sterility, smaller seeds, pure white seed coat color and high yields. Lines with these induced desirable characteristics were

  9. Characterization of ultraviolet light-induced diphtheria toxin-resistant mutations in normal and Xeroderma pigmentosum human fibroblasts

    International Nuclear Information System (INIS)

    Glover, T.W.

    1979-01-01

    Quantitative mutagenesis studies in human cells have been severely limited by the lack of reliable genetic markers. Experiments were therefore performed to develop and characterize a better quantitative mutation assay for human cells. The uv-induction of diphtheria toxin resistant (DT/sup r/) mutations in normal and excision repair defective xeroderma pigmentosum (XP) fibroblasts has been quantitatively characterized. A concentration of diphtheria toxin to use in the selection of resistant mutants was determined whereby DT/sup r/ cells are cross-resistant to Pseudomonas aeurginosa exotoxin A, indicating mutants have altered elongation factor-2 (EF-2) which is not susceptible to ADP-ribosylation by either toxin. Results of this study indicate that XP fibroblasts have higher uv-induced mutation frequencies per unit uv-dose but similar frequencies per unit survival compared to normal cells as measured using a new genetic marker for quantitative mutagenesis. Furthermore, these results support a prediction of the mutation theory of cancer, namely, that cells from individuals with certain human syndromes that predispose the individual to cancer will have higher induced mutation frequencies than cells from non-susceptible individuals. This newly characterized genetic marker should be useful in quantitative mutagenesis studies in human cells

  10. Development of a PCR/LDR/capillary electrophoresis assay with potential for the detection of a beta-thalassemia fetal mutation in maternal plasma.

    Science.gov (United States)

    Yi, Ping; Chen, Zhuqin; Yu, Lili; Zheng, Yingru; Liu, Guodong; Xie, Haichang; Zhou, Yuanguo; Zheng, Xiuhui; Han, Jian; Li, Li

    2010-08-01

    Analysis of fetal DNA in maternal plasma has recently been introduced for non-invasive prenatal diagnosis. We have now investigated the feasibility of polymerase chain reaction (PCR)/ligase detection reaction (LDR)/capillary electrophoresis for the detection of fetal point mutations, such as the beta-thalassemia mutation, IVS2 654(C --> T), in maternal plasma DNA. The sensitivity of LDR/capillary electrophoresis was examined by quantifying the mutant PCR products in the presence of a vast excess of non-mutant competitor template, a situation that mimics the detection of rare fetal mutations in the presence of excess maternal DNA. PCR/LDR/capillary electrophoresis was applied to detect the mutation, IVS2 654(C --> T), in an experimental model at different sensitivity levels and from 10 maternal plasma samples. Our results demonstrated that this approach to detect a low abundance IVS2 654(C --> T) mutation achieved a sensitivity of approximately 1:10,000. The approach was applied to maternal plasma DNA to detect the paternally inherited fetal IVS2 654(C --> T) mutation, and the results were equivalent to those obtained by PCR/reverse dot blot of amniotic fluid cell DNA. PCR/LDR/capillary electrophoresis has a very high sensitivity that can distinguish low abundance single nucleotide differences and can detect paternally inherited fetal point mutations in maternal plasma.

  11. Membrane Composition and Physiological Activity of Plastids from an Oenothera Plastome