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Sample records for genetically modified maize

  1. Nutritional evaluation of genetically modified maize corn performed on rats.

    PubMed

    Chrenková, Mária; Sommer, A; Ceresnáková, Zuzana; Nitrayová, Sona; Prostredná, Miroslava

    2002-06-01

    The aim of this study was to determine the composition and nutritional value of conventional and transgenic, so-called Roundup Ready (RR) maize with an introduced gene of glyphosate resistance. Crude protein, crude fibre, ash, fat, starch, sugar, amino acids, fatty acid and macroelement levels were determined by chemical analysis. In both maize lines a low level of Ca (0.15 g.kg-1 DM) and of the essential amino acids lysine and tryptophan (2.6 and 1.7 g.kg-1 DM, respectively) were observed. In the biological experiment carried out on rats the tested maize lines were the only dietary sources of nitrogen, thus, the experimental diets contained 9% CP in dietary dry matter. In the feeding experiment no significant differences in the protein efficiency ratio (PER) were observed between groups receiving conventional or transgenic maize (1.51 and 1.41, respectively). Also almost equal results were obtained in the balance experiments. Both maize lines revealed a high nitrogen digestibility (84.9 and 84.5%, respectively) and the net protein utilization amounted to 63.5 and 63.2%, respectively. From these results can be concluded that regarding nutrient composition and utilisation, genetically modified (RR) maize is equivalent to isogenic maize.

  2. Cross-fertilization between genetically modified and non-genetically modified maize crops in Uruguay.

    PubMed

    Galeano, Pablo; Debat, Claudio Martínez; Ruibal, Fabiana; Fraguas, Laura Franco; Galván, Guillermo A

    2010-01-01

    The cultivation of genetically modified (GM) Bt maize (Zea mays L.) events MON810 and Bt11 is permitted in Uruguay. Local regulations specify that 10% of the crop should be a non-GM cultivar as refuge area for biodiversity, and the distance from other non-GM maize crops should be more than 250 m in order to avoid cross-pollination. However, the degree of cross-fertilization between maize crops in Uruguay is unknown. The level of adventitious presence of GM material in non-GM crops is a relevant issue for organic farming, in situ conservation of genetic resources and seed production. In the research reported here, the occurrence and frequency of cross-fertilization between commercial GM and non-GM maize crops in Uruguay was assessed. The methodology comprised field sampling and detection using DAS-ELISA and PCR. Five field-pair cases where GM maize crops were grown near non-GM maize crops were identified. These cases had the potential to cross-fertilize considering the distance between crops and the similarity of the sowing dates. Adventitious presence of GM material in the offspring of non-GM crops was found in three of the five cases. Adventitious presence of event MON810 or Bt11 in non-GM maize, which were distinguished using specific primers, matched the events in the putative sources of transgenic pollen. Percentages of transgenic seedlings in the offspring of the non-GM crops were estimated as 0.56%, 0.83% and 0.13% for three sampling sites with distances of respectively 40, 100 and 330 m from the GM crops. This is a first indication that adventitious presence of transgenes in non-GM maize crops will occur in Uruguay if isolation by distance and/or time is not provided. These findings contribute to the evaluation of the applicability of the "regulated coexistence policy" in Uruguay.

  3. Fate of maize intrinsic and recombinant genes in calves fed genetically modified maize Bt11.

    PubMed

    Chowdhury, Emdadull H; Mikami, Osamu; Murata, Hideo; Sultana, Parvin; Shimada, Nobuaki; Yoshioka, Miyako; Guruge, Keerthi S; Yamamoto, Sachiko; Miyazaki, Shigeru; Yamanaka, Noriko; Nakajima, Yasuyuki

    2004-02-01

    The presence of maize intrinsic and recombinant cry1Ab genes in the gastrointestinal (GI) contents, peripheral blood mononuclear cells (PBMC), and visceral organs of calves fed genetically modified Bt11 maize was examined by PCR in a subchronic 90-day performance study. Samples were collected from six Japanese Black/Holstein calves fed Bt11 maize and from six calves fed non-Bt maize. Fragments of maize zein (Ze1), invertase, chloroplast, and cry1Ab were detected inconsistently in the rumen fluid and rectal contents 5 and 18 h after feeding. The chloroplast DNA fragments of ribulose-1,5-bisphosphate carboxylase/oxygenase and tRNA were detected inconsistently in the PBMC, the visceral organs, and the longissimus muscle, while the cry1Ab gene was never detected in PBMC or in the visceral organs. These results suggest that feed-derived maize DNA was mostly degraded in the GI tract but that fragmented DNA was detectable in the GI contents as a possible source of transfer to calf tissues. These results also suggest that the recombinant cry1Ab genes were not transferred to the PBMC and tissues of calves fed Bt11 maize.

  4. Real-time quantitative polymerase chain reaction methods for four genetically modified maize varieties and maize DNA content in food.

    PubMed

    Brodmann, Peter D; Ilg, Evelyn C; Berthoud, Hélène; Herrmann, Andre

    2002-01-01

    Quantitative detection methods are needed for enforcement of the recently introduced labeling threshold for genetically modified organisms (GMOs) in food ingredients. This labeling threshold, which is set to 1% in the European Union and Switzerland, must be applied to all approved GMOs. Four different varieties of maize are approved in the European Union: the insect-resistant Bt176 maize (Maximizer), Btl 1 maize, Mon810 (YieldGard) maize, and the herbicide-tolerant T25 (Liberty Link) maize. Because the labeling must be considered individually for each ingredient, a quantitation system for the endogenous maize content is needed in addition to the GMO-specific detection systems. Quantitative real-time polymerase chain reaction detection methods were developed for the 4 approved genetically modified maize varieties and for an endogenous maize (invertase) gene system.

  5. Individual detection of genetically modified maize varieties in non-identity-preserved maize samples.

    PubMed

    Akiyama, Hiroshi; Sakata, Kozue; Kondo, Kazunari; Tanaka, Asako; Liu, Ming S; Oguchi, Taichi; Furui, Satoshi; Kitta, Kazumi; Hino, Akihiro; Teshima, Reiko

    2008-03-26

    In many countries, the labeling of grains and feed- and foodstuffs is mandatory if the genetically modified organism (GMO) content exceeds a certain level of approved GM varieties. The GMO content in a maize sample containing the combined-trait (stacked) GM maize as determined by the currently available methodology is likely to be overestimated. However, there has been little information in the literature on the mixing level and varieties of stacked GM maize in real sample grains. For the first time, the GMO content of non-identity-preserved (non-IP) maize samples imported from the United States has been successfully determined by using a previously developed individual kernel detection system coupled to a multiplex qualitative PCR method followed by multichannel capillary gel electrophoresis system analysis. To clarify the GMO content in the maize samples imported from the United States, determine how many stacked GM traits are contained therein, and which GM trait varieties frequently appeared in 2005, the GMO content (percent) on a kernel basis and the varieties of the GM kernels in the non-IP maize samples imported from the United States were investigated using the individual kernel analysis system. The average (+/-standard deviation) of the GMO contents on a kernel basis in five non-IP sample lots was determined to be 51.0+/-21.6%, the percentage of a single GM trait grains was 39%, and the percentage of the stacked GM trait grains was 12%. The MON810 grains and NK603 grains were the most frequent varieties in the single GM traits. The most frequent stacked GM traits were the MON810xNK603 grains. In addition, the present study would provide the answer and impact for the quantification of GM maize content in the GM maize kernels on labeling regulation.

  6. Effect of feeding cows genetically modified maize on the bacterial community in the bovine rumen.

    PubMed

    Wiedemann, S; Gürtler, P; Albrecht, C

    2007-12-01

    Rumen-cannulated cows (n = 4) were fed successively silage made from either conventional or genetically modified (GM) maize. Results revealed no effects of GM maize on the dynamics of six ruminal bacterial strains (investigated by real-time PCR) compared to the conventional maize silage.

  7. [Contamination with genetically modified maize MON863 of processed foods on the market].

    PubMed

    Ohgiya, Yoko; Sakai, Masaaki; Miyashita, Taeko; Yano, Koichi

    2009-06-01

    Genetically modified maize MON863 (MON863), which has passed a safety examination in Japan, is commercially cultivated in the United States as a food and a resource for fuel. Maize is an anemophilous flower, which easily hybridizes. However, an official method for quantifying the content of MON863 has not been provided yet in Japan. We here examined MON863 contamination in maize-processed foods that had no labeling indicating of the use of genetically modified maize.From March 2006 to July 2008, we purchased 20 frozen maize products, 8 maize powder products, 7 canned maize products and 4 other maize processed foods. Three primer pairs named MON 863 primer, MON863-1, and M3/M4 for MON863-specific integrated cassette were used for qualitative polymerase chain reaction (PCR). A primer pair "SSIIb-3" for starch synthase gene was used to confirm the quality of extracted DNA. The starch synthase gene was detected in all samples. In qualitative tests, the MON863-specific fragments were detected in 7 (18%) maize powder products out of the 39 processed foods with all the three primer pairs.We concluded that various maize processed foods on the market were contaminated with MON863. It is important to accumulate further information on MON863 contamination in maize-processed foods that have no label indication of the use of genetically modified maize.

  8. Risks and benefits of genetically modified maize donations to southern Africa: views from Malawi.

    PubMed

    Muula, Adamson S; Mfutso-Bengo, Joseph M

    2003-02-01

    In 2001 and 2002, many countries in the Southern African Development Community (SADC) have suffered from severe food shortages resulting in an estimated 14 million people facing starvation due to inadequate quantities of the staple maize. The international community's response has been the donation of foodstuffs, including genetically modified maize. Reactions of the recipient countries of Zambia, Zimbabwe, and Malawi have been different. Zambia appealed to the donors not to send genetically modified maize, whereas Malawi accepted the maize donations. Malawi is currently facing many public health challenges because 10% of its 10-million population is HIV-positive, maternal mortality rate has almost doubled between 1992 and 2000, and there are also an estimated 1 million orphans due to HIV/AIDS. In the European Union, genetically modified maize falls under "Novel Foods" and its marketing and distribution are strictly regulated by law. This has never been the case in the southern African countries. In this article, we discuss the ethical challenges associated with genetically modified maize donations to southern Africa. Although genetically modified food offers a way to avoid many adverse effects of food shortages, we believe that some of the ethical questions of genetically modified food donations should be solved first, under the leadership of the donor countries and partnership of the developing countries. There are fears that consummation of genetically modified maize could have adverse health effects. These fears must be addressed if the confidence of developing countries in the donor community is to be maintained.

  9. Fungal growth and fusarium mycotoxin content in isogenic traditional maize and genetically modified maize grown in France and Spain.

    PubMed

    Bakan, B; Melcion, D; Richard-Molard, D; Cahagnier, B

    2002-02-13

    Fungi of the genus Fusarium are common fungal contaminants of maize and are also known to produce mycotoxins. Maize that has been genetically modified to express a Bt endotoxin has been used to study the effect of insect resistance on fungal infection of maize grains by Fusarium species and their related mycotoxins. Maize grain from Bt hybrids and near-isogenic traditional hybrids was collected in France and Spain from the 1999 crop, which was grown under natural conditions. According to the ergosterol level, the fungal biomass formed on Bt maize grain was 4-18 times lower than that on isogenic maize. Fumonisin B(1) grain concentrations ranged from 0.05 to 0.3 ppm for Bt maize and from 0.4 to 9 ppm for isogenic maize. Moderate to low concentrations of trichothecenes and zearalenone were measured on transgenic as well as on non-transgenic maize. Nevertheless, significant differences were obtained in certain regions. The protection of maize plants against insect damage (European corn borer and pink stem borer) through the use of Bt technology seems to be a way to reduce the contamination of maize by Fusarium species and the resultant fumonisins in maize grain grown in France and Spain.

  10. Prevalence of genetically modified rice, maize, and soy in Saudi food products.

    PubMed

    Elsanhoty, Rafaat M; Al-Turki, A I; Ramadan, Mohamed Fawzy

    2013-10-01

    Qualitative and quantitative DNA-based methods were applied to detect genetically modified foods in samples from markets in the Kingdom of Saudi Arabia. Two hundred samples were collected from Al-Qassim, Riyadh, and Mahdina in 2009 and 2010. GMOScreen 35S and NOS test kits for the detection of genetically modified organism varieties in samples were used. The positive results obtained from GMOScreen 35S and NOS were identified using specific primer pairs. The results indicated that all rice samples gave negative results for the presence of 35S and NOS terminator. About 26 % of samples containing soybean were positive for 35S and NOS terminator and 44 % of samples containing maize were positive for the presence of 35S and/or NOS terminator. The results showed that 20.4 % of samples was positive for maize line Bt176, 8.8 % was positive for maize line Bt11, 8.8 % was positive for maize line T25, 5.9 % was positive for maize line MON 810, and 5.9 % was positive for StarLink maize. Twelve samples were shown to contain <3 % of genetically modified (GM) soy and 6 samples >10 % of GM soy. Four samples containing GM maize were shown to contain >5 % of GM maize MON 810. Four samples containing GM maize were shown to contain >1 % of StarLink maize. Establishing strong regulations and certified laboratories to monitor GM foods or crops in Saudi market is recommended.

  11. Quantitative detection system for maize sample containing combined-trait genetically modified maize.

    PubMed

    Akiyama, Hiroshi; Watanabe, Takahiro; Wakabayashi, Kaoru; Nakade, Shinsuke; Yasui, Shuji; Sakata, Kozue; Chiba, Ryoko; Spiegelhalter, Frank; Hino, Akihiro; Maitani, Tamio

    2005-11-15

    Various countries have established regulations that stipulate the labeling of agricultural commodities, feed, and food products that contain or are made from genetically modified (GM) material or that contain adventitious GM material in amounts that exceed certain threshold levels. While regulations in some countries refer to GM material on a weight per weight (w/w) percentage, the currently applied detection methods do not directly measure the w/w percentage of the GM material. Depending on the particular method and the sample matrix it is applied to, the conversion of analytical results to a w/w percentage is challenging or not possible. The first rapid PCR system for GM maize detection on a single kernel basis has been developed. The equipment for the grinding of individual kernels and a silica membrane-based 96-well DNA extraction kit were both significantly revised and optimized for this particular purpose, respectively. We developed a multiplex real-time PCR method for the rapid quantification of GM DNA sequences in the obtained DNA solutions. In addition, a multiplex qualitative PCR detection method allows for the simultaneous detection of different GM maize traits in each kernel and thereby for identification of individual kernels that contain a combination of two or more GM traits. Especially for grain samples that potentially contain combined-trait GM maize kernels, the proposed methods can deliver informative results in a rapid, precise, and reliable manner.

  12. A multiplex PCR method of detecting recombinant DNAs from five lines of genetically modified maize.

    PubMed

    Matsuoka, T; Kuribara, H; Akiyama, H; Miura, H; Goda, Y; Kusakabe, Y; Isshiki, K; Toyoda, M; Hino, A

    2001-02-01

    Seven lines of genetically modified (GM) maize have been authorized in Japan as foods and feeds imported from the USA. We improved a multiplex PCR method described in the previous report in order to distinguish the five lines of GM maize. Genomic DNA was extracted from GM maize with a silica spin column kit, which could reduce experimental time and improve safety in the laboratory and potentially in the environment. We sequenced recombinant DNA (r-DNA) introduced into GM maize, and re-designed new primer pairs to increase the specificity of PCR to distinguish five lines of GM maize by multiplex PCR. A primer pair for the maize intrinsic zein gene (Ze1) was also designed to confirm the presence of amplifiable maize DNA. The lengths of PCR products using these six primer pairs were different. The Ze1 and the r-DNAs from the five lines of GM maize were qualitatively detected in one tube. The specific PCR bands were distinguishable from each other on the basis of the expected length. The r-DNA could be detected from maize samples containing 0.5% of each of the five lines of GM maize. The sensitivity would be acceptable to secure the verification of non-GMO materials and to monitor the reliability of the labeling system.

  13. Maize plants infestation by Fusarium spp. and deoxynivalenol in genetically modified corn hybrid and traditional maize cultivars.

    PubMed

    Selwet, Marek

    2011-01-01

    The objective of the performed investigations was to isolate pathogenic fungi from contaminated maize cobs, to assess the appearance of maize cob fusariosis and to determine grain contamination with deoxynivalenol in the cultivation of genetically modified maize containing a gene resistance against European corn borer (Ostrinia nubilalis Hbn) as well as selected non-modified cultivars. The plant material comprised the following genetically modified maize cultivar: DKC 3421 YG (MON 810) and non-modified cultivars obtained from Smolice Plant Breeding Ltd., IHAR Group: Junak (FAO 210-220), Prosna (FAO 220), SMH (FAO 230), Baca (FAO 220). Prior to harvesting, the occurrence of maize cob fusariosis was determined in the 89 (BBCH) developmental ripening stage. Microbiological assessment was carried out on grains selected from cobs characterized by various pathological symptoms. In 2008, a total of 133 isolates was obtained from the examined samples of infected maize plants, of which 51 isolates were species-identified, while in 2009, the total of 123 isolates were determined, of which 63 were species-identified. In both experimental years, the majority of isolates contained fungi from the Fusarium genus. The performed analysis of mean levels of cob contamination by fusarioses revealed that DKC 3421 YG (MON 810) and SMH (FAO 230) cultivars showed the smallest levels of contamination as well as the lowest percent of cob contamination per plant, while Junak (FAO 210-220) and Baca (FAO 220) cultivars were characterized by the highest degree of contamination. The lowest deoxynivalenol concentrations were determined in years 2008 and 2009 in the case of the DKC 3421 YG (MON 810) cultivar, whereas Prosna (FAO 220) cultivar was characterized by the highest deoxynivalenol concentration.

  14. Comparative impact of genetically modified and non modified maize (Zea mays L.) on succeeding crop and associated weed.

    PubMed

    Ibrahim, Muhammad; Ahmed, Naseer; Ullah, Faizan; Shinwari, Zabta Khan; Bano, Asghari

    2016-04-01

    This research work documents the comparative impact of genetically modified (GM) (insect resistance) and non modified maize (Zea mays L.) on growth and germination of succeeding crop wheat (Triticum aestivum L.) and associated weed (Avena fatua L.). The aqueous extracts of both the GM and non-GM maize exhibited higher phenolic content than that of methanolic extracts. Germination percentage and germination index of wheat was significantly decreased by GM methanolic extract (10%) as well as that of non-GM maize at 3% aqueous extract. Similarly germination percentage of weed (Avena fatua L.) was significantly reduced by application of 3% and 5% methanolic GM extracts. All extracts of GM maize showed non-significant effect on the number of roots, root length and shoot length per plant but 5% and 10% methanolic extracts of non-GM maize significantly increased the number of roots per plant of wheat seedling. Similarly, 10% methanolic extract of GM maize significantly increased the number of roots per plant of weed seedling. Methanolic extracts of GM and non-GM maize (3% and 5%) significantly decreased the protease activity in wheat as compared to untreated control.

  15. Fate of genetically modified maize DNA in the oral cavity and rumen of sheep.

    PubMed

    Duggan, Paula S; Chambers, Philip A; Heritage, John; Michael Forbes, J

    2003-02-01

    The polymerase chain reaction (PCR) technique was used to investigate the fate of a transgene in the rumen of sheep fed silage and maize grains from an insect-resistant maize line. A 1914-bp DNA fragment containing the entire coding region of the synthetic cryIA(b) gene was still amplifiable from rumen fluid sampled 5 h after feeding maize grains. The same target sequence, however, could not be amplified from rumen fluid sampled from sheep fed silage prepared from the genetically modified maize line. PCR amplification of a shorter (211-bp), yet still highly specific, target sequence was possible with rumen fluid sampled up to 3 and 24 h after feeding silage and maize grains, respectively. These findings indicate that intact transgenes from silage are unlikely to survive significantly in the rumen since a DNA sequence 211-bp long is very unlikely to transmit genetic information. By contrast, DNA in maize grains persists for a significant time and may, therefore, provide a source of transforming DNA in the rumen. In addition, we have examined the biological activity of plasmid DNA that had previously been exposed to the ovine oral cavity. Plasmid extracted from saliva sampled after incubation for 8 min was still capable of transforming competent Escherichia coli to kanamycin resistance, implying that DNA released from the diet within the mouth may retain sufficient biological activity for the transformation of competent oral bacteria.

  16. Detection of genetically modified maize in processed foods sold commercially in iran by qualitative PCR.

    PubMed

    Rabiei, Maryam; Mehdizadeh, Mehrangiz; Rastegar, Hossein; Vahidi, Hossein; Alebouyeh, Mahmoud

    2013-01-01

    Detection of genetically modified organisms (GMOs) in food is an important issue for all the subjects involved in food control and customer's right. Due to the increasing number of GMOs imported to Iran during the past few years, it has become necessary to screen the products in order to determine the identity of the consumed daily foodstuffs. In this study, following the extraction of genomic DNA from processed foods sold commercially in Iran, qualitative PCR was performed to detect genetically modified maize. The recombinant DNA target sequences were detected with primers highly specific for each investigated transgene such as CaMV35s gene, Bt-11, MON810 and Bt-176 separately. Based on the gel electrophoresis results, Bt- 11 and MON810 events were detected in some maize samples, while, in none of them Bt- 176 modified gene was detected. For the first time, the results demonstrate the presence of genetically modified maize in Iranian food products, reinforcing the need for the development of labeling system and valid quantitative methods in routine analyses.

  17. Loop-mediated isothermal amplification (LAMP) method for detection of genetically modified maize T25.

    PubMed

    Xu, Junyi; Zheng, Qiuyue; Yu, Ling; Liu, Ran; Zhao, Xin; Wang, Gang; Wang, Qinghua; Cao, Jijuan

    2013-11-01

    The loop-mediated isothermal amplification (LAMP) assay indicates a potential and valuable means for genetically modified organism (GMO) detection especially for its rapidity, simplicity, and low cost. We developed and evaluated the specificity and sensitivity of the LAMP method for rapid detection of the genetically modified (GM) maize T25. A set of six specific primers was successfully designed to recognize six distinct sequences on the target gene, including a pair of inner primers, a pair of outer primers, and a pair of loop primers. The optimum reaction temperature and time were verified to be 65°C and 45 min, respectively. The detection limit of this LAMP assay was 5 g kg(-1) GMO component. Comparative experiments showed that the LAMP assay was a simple, rapid, accurate, and specific method for detecting the GM maize T25.

  18. Functional diversity of staphylinid beetles (Coleoptera: Staphylinidae) in maize fields: testing the possible effect of genetically modified, insect resistant maize.

    PubMed

    Svobodová, Z; Skoková Habuštová, O; Boháč, J; Sehnal, F

    2016-08-01

    Staphylinid beetles are recommended bioindicators for the pre-market environmental risk assessment of genetically modified (GM) insect protected maize expressing the Cry3Bb1 toxin. Our multiannual study is a unique European analysis of a staphylinid community within a 14 ha maize field. GM maize, its near-isogenic hybrid (with or without insecticide treatment), and two other reference hybrids were each grown in five 0.5 ha plots. The opportunity for exposure to Cry toxin from plant residues ploughed into the soil was shown by the presence of saprophagous dipteran larvae that are common prey of predatory staphylinid species and hosts of the parasitoid species. 2587 individuals belonging to 77 staphylinid species were sampled using pitfall traps. Lesteva longoelytrata (31%), Oxypoda acuminata (12%), Aloconota sulcifrons (8%) and Anotylus rugosus (7%) were the most abundant beetles in the field. Bionomics, food specialization, temperature requirements and size group were assigned for 25 most common species. These traits determine the occurrence of staphylinid beetles in the field, the food sources they could utilize and thus also their likely contact with the Cry3Bb1 toxin. Statistical analysis of activity abundance, Rao indices and multivariate analysis of distribution of particular categories of functional traits in the field showed negligible effects of the experimental treatments, including the GM maize, upon the staphylinid community. Staphylinid beetles represent a considerably diverse part of epigeic field fauna with wide food specialization; these features render them suitable for the assessment of environmental safety of GM insect protected maize. However, the availability of prey and the presence of particular staphylinid species and their abundance are highly variable; this complicates the interpretation of the results.

  19. Event-specific quantitative detection of nine genetically modified maizes using one novel standard reference molecule.

    PubMed

    Yang, Litao; Guo, Jinchao; Pan, Aihu; Zhang, Haibo; Zhang, Kewei; Wang, Zhengming; Zhang, Dabing

    2007-01-10

    With the development of genetically modified organism (GMO) detection techniques, the Polymerase Chain Reaction (PCR) technique has been the mainstay for GMO detection, and real-time PCR is the most effective and important method for GMO quantification. An event-specific detection strategy based on the unique and specific integration junction sequences between the host plant genome DNA and the integrated gene is being developed for its high specificity. This study establishes the event-specific detection methods for TC1507 and CBH351 maizes. In addition, the event-specific TaqMan real-time PCR detection methods for another seven GM maize events (Bt11, Bt176, GA21, MON810, MON863, NK603, and T25) were systematically optimized and developed. In these PCR assays, the fluorescent quencher, TAMRA, was dyed on the T-base of the probe at the internal position to improve the intensity of the fluorescent signal. To overcome the difficulties in obtaining the certified reference materials of these GM maizes, one novel standard reference molecule containing all nine specific integration junction sequences of these GM maizes and the maize endogenous reference gene, zSSIIb, was constructed and used for quantitative analysis. The limits of detection of these methods were 20 copies for these different GM maizes, the limits of quantitation were about 20 copies, and the dynamic ranges for quantification were from 0.05 to 100% in 100 ng of DNA template. Furthermore, nine groups of the mixed maize samples of these nine GM maize events were quantitatively analyzed to evaluate the accuracy and precision. The accuracy expressed as bias varied from 0.67 to 28.00% for the nine tested groups of GM maize samples, and the precision expressed as relative standard deviations was from 0.83 to 26.20%. All of these indicated that the established event-specific real-time PCR detection systems and the reference molecule in this study are suitable for the identification and quantification of these GM

  20. Determination of Mycotoxin Production of Fusarium Species in Genetically Modified Maize Varieties by Quantitative Flow Immunocytometry

    PubMed Central

    Bánáti, Hajnalka; Darvas, Béla; Fehér-Tóth, Szilvia; Czéh, Árpád; Székács, András

    2017-01-01

    Levels of mycotoxins produced by Fusarium species in genetically modified (GM) and near-isogenic maize, were determined using multi-analyte, microbead-based flow immunocytometry with fluorescence detection, for the parallel quantitative determination of fumonisin B1, deoxynivalenol, zearalenone, T-2, ochratoxin A, and aflatoxin B1. Maize varieties included the genetic events MON 810 and DAS-59122-7, and their isogenic counterparts. Cobs were artificially infested by F. verticillioides and F. proliferatum conidia, and contained F. graminearum and F. sporotrichoides natural infestation. The production of fumonisin B1 and deoxynivalenol was substantially affected in GM maize lines: F. verticillioides, with the addition of F. graminearum and F. sporotrichoides, produced significantly lower levels of fumonisin B1 (~300 mg·kg−1) in DAS-59122-7 than in its isogenic line (~580 mg·kg−1), while F. proliferatum, in addition to F. graminearum and F. sporotrichoides, produced significantly higher levels of deoxynivalenol (~18 mg·kg−1) in MON 810 than in its isogenic line (~5 mg·kg−1). Fusarium verticillioides, with F. graminearum and F. sporotrichoides, produced lower amounts of deoxynivalenol and zearalenone than F. proliferatum, with F. graminearum and F. sporotrichoides. T-2 toxin production remained unchanged when considering the maize variety. The results demonstrate the utility of the Fungi-Plex™ quantitative flow immunocytometry method, applied for the high throughput parallel determination of the target mycotoxins. PMID:28241411

  1. Finding the joker among the maize endogenous reference genes for genetically modified organism (GMO) detection.

    PubMed

    Paternò, Annalisa; Marchesi, Ugo; Gatto, Francesco; Verginelli, Daniela; Quarchioni, Cinzia; Fusco, Cristiana; Zepparoni, Alessia; Amaddeo, Demetrio; Ciabatti, Ilaria

    2009-12-09

    The comparison of five real-time polymerase chain reaction (PCR) methods targeted at maize ( Zea mays ) endogenous sequences is reported. PCR targets were the alcohol dehydrogenase (adh) gene for three methods and high-mobility group (hmg) gene for the other two. The five real-time PCR methods have been checked under repeatability conditions at several dilution levels on both pooled DNA template from several genetically modified (GM) maize certified reference materials (CRMs) and single CRM DNA extracts. Slopes and R(2) coefficients of all of the curves obtained from the adopted regression model were compared within the same method and among all of the five methods, and the limit of detection and limit of quantitation were analyzed for each PCR system. Furthermore, method equivalency was evaluated on the basis of the ability to estimate the target haploid genome copy number at each concentration level. Results indicated that, among the five methods tested, one of the hmg-targeted PCR systems can be considered equivalent to the others but shows the best regression parameters and a higher repeteability along the dilution range. Thereby, it is proposed as a valid module to be coupled to different event-specific real-time PCR for maize genetically modified organism (GMO) quantitation. The resulting practicability improvement on the analytical control of GMOs is discussed.

  2. Mass spectrometric detection of CP4 EPSPS in genetically modified soya and maize.

    PubMed

    Ocaña, Mireia Fernández; Fraser, Paul D; Patel, Raj K P; Halket, John M; Bramley, Peter M

    2007-01-01

    The potential of protein fractionation hyphenated to mass spectrometry (MS) to detect and characterize the transgenic protein present in Roundup Ready soya and maize has been investigated. Genetically modified (GM) soya and maize contain the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene from Agrobacterium tumefaciens CP4, which confers resistance to the herbicide glyphosate. The GM soya and maize proteomes were fractionated by gel filtration, anion-exchange chromatography and sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS-PAGE) prior to MS. This facilitated detection of a tryptic peptide map of CP4 EPSPS by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS and nanoelectrospray ionization quadrupole time-of-flight (nanoESI-QTOF) MS. Subsequently, sequence information from the CP4 EPSPS tryptic peptides was obtained by nanoESI-QTOF MS/MS. The identification was accomplished in 0.9% GM soya seeds, which is the current EU threshold for food-labeling requirements.

  3. DNA extraction techniques compared for accurate detection of genetically modified organisms (GMOs) in maize food and feed products.

    PubMed

    Turkec, Aydin; Kazan, Hande; Karacanli, Burçin; Lucas, Stuart J

    2015-08-01

    In this paper, DNA extraction methods have been evaluated to detect the presence of genetically modified organisms (GMOs) in maize food and feed products commercialised in Turkey. All the extraction methods tested performed well for the majority of maize foods and feed products analysed. However, the highest DNA content was achieved by the Wizard, Genespin or the CTAB method, all of which produced optimal DNA yield and purity for different maize food and feed products. The samples were then screened for the presence of GM elements, along with certified reference materials. Of the food and feed samples, 8 % tested positive for the presence of one GM element (NOS terminator), of which half (4 % of the total) also contained a second element (the Cauliflower Mosaic Virus 35S promoter). The results obtained herein clearly demonstrate the presence of GM maize in the Turkish market, and that the Foodproof GMO Screening Kit provides reliable screening of maize food and feed products.

  4. Molecular responses of genetically modified maize to abiotic stresses as determined through proteomic and metabolomic analyses.

    PubMed

    Benevenuto, Rafael Fonseca; Agapito-Tenfen, Sarah Zanon; Vilperte, Vinicius; Wikmark, Odd-Gunnar; van Rensburg, Peet Jansen; Nodari, Rubens Onofre

    2017-01-01

    Some genetically modified (GM) plants have transgenes that confer tolerance to abiotic stressors. Meanwhile, other transgenes may interact with abiotic stressors, causing pleiotropic effects that will affect the plant physiology. Thus, physiological alteration might have an impact on the product safety. However, routine risk assessment (RA) analyses do not evaluate the response of GM plants exposed to different environmental conditions. Therefore, we here present a proteome profile of herbicide-tolerant maize, including the levels of phytohormones and related compounds, compared to its near-isogenic non-GM variety under drought and herbicide stresses. Twenty differentially abundant proteins were detected between GM and non-GM hybrids under different water deficiency conditions and herbicide sprays. Pathway enrichment analysis showed that most of these proteins are assigned to energetic/carbohydrate metabolic processes. Among phytohormones and related compounds, different levels of ABA, CA, JA, MeJA and SA were detected in the maize varieties and stress conditions analysed. In pathway and proteome analyses, environment was found to be the major source of variation followed by the genetic transformation factor. Nonetheless, differences were detected in the levels of JA, MeJA and CA and in the abundance of 11 proteins when comparing the GM plant and its non-GM near-isogenic variety under the same environmental conditions. Thus, these findings do support molecular studies in GM plants Risk Assessment analyses.

  5. Molecular responses of genetically modified maize to abiotic stresses as determined through proteomic and metabolomic analyses

    PubMed Central

    Benevenuto, Rafael Fonseca; Agapito-Tenfen, Sarah Zanon; Vilperte, Vinicius; Wikmark, Odd-Gunnar; van Rensburg, Peet Jansen; Nodari, Rubens Onofre

    2017-01-01

    Some genetically modified (GM) plants have transgenes that confer tolerance to abiotic stressors. Meanwhile, other transgenes may interact with abiotic stressors, causing pleiotropic effects that will affect the plant physiology. Thus, physiological alteration might have an impact on the product safety. However, routine risk assessment (RA) analyses do not evaluate the response of GM plants exposed to different environmental conditions. Therefore, we here present a proteome profile of herbicide-tolerant maize, including the levels of phytohormones and related compounds, compared to its near-isogenic non-GM variety under drought and herbicide stresses. Twenty differentially abundant proteins were detected between GM and non-GM hybrids under different water deficiency conditions and herbicide sprays. Pathway enrichment analysis showed that most of these proteins are assigned to energetic/carbohydrate metabolic processes. Among phytohormones and related compounds, different levels of ABA, CA, JA, MeJA and SA were detected in the maize varieties and stress conditions analysed. In pathway and proteome analyses, environment was found to be the major source of variation followed by the genetic transformation factor. Nonetheless, differences were detected in the levels of JA, MeJA and CA and in the abundance of 11 proteins when comparing the GM plant and its non-GM near-isogenic variety under the same environmental conditions. Thus, these findings do support molecular studies in GM plants Risk Assessment analyses. PMID:28245233

  6. First application of a microsphere-based immunoassay to the detection of genetically modified organisms (GMOs): quantification of Cry1Ab protein in genetically modified maize.

    PubMed

    Fantozzi, Anna; Ermolli, Monica; Marini, Massimiliano; Scotti, Domenico; Balla, Branko; Querci, Maddalena; Langrell, Stephen R H; Van den Eede, Guy

    2007-02-21

    An innovative covalent microsphere immunoassay, based on the usage of fluorescent beads coupled to a specific antibody, was developed for the quantification of the endotoxin Cry1Ab present in MON810 and Bt11 genetically modified (GM) maize lines. In particular, a specific protocol was developed to assess the presence of Cry1Ab in a very broad range of GM maize concentrations, from 0.1 to 100% [weight of genetically modified organism (GMO)/weight]. Test linearity was achieved in the range of values from 0.1 to 3%, whereas fluorescence signal increased following a nonlinear model, reaching a plateau at 25%. The limits of detection and quantification were equal to 0.018 and 0.054%, respectively. The present study describes the first application of quantitative high-throughput immunoassays in GMO analysis.

  7. Lack of Detectable Allergenicity in Genetically Modified Maize Containing “Cry” Proteins as Compared to Native Maize Based on In Silico & In Vitro Analysis

    PubMed Central

    Mathur, Chandni; Kathuria, Pooran C.; Dahiya, Pushpa; Singh, Anand B.

    2015-01-01

    Background Genetically modified, (GM) crops with potential allergens must be evaluated for safety and endogenous IgE binding pattern compared to native variety, prior to market release. Objective To compare endogenous IgE binding proteins of three GM maize seeds containing Cry 1Ab,1Ac,1C transgenic proteins with non GM maize. Methods An integrated approach of in silico & in vitro methods was employed. Cry proteins were tested for presence of allergen sequence by FASTA in allergen databases. Biochemical assays for maize extracts were performed. Specific IgE (sIgE) and Immunoblot using food sensitized patients sera (n = 39) to non GM and GM maize antigens was performed. Results In silico approaches, confirmed for non sequence similarity of stated transgenic proteins in allergen databases. An insignificant (p> 0.05) variation in protein content between GM and non GM maize was observed. Simulated Gastric Fluid (SGF) revealed reduced number of stable protein fractions in GM then non GM maize which might be due to shift of constituent protein expression. Specific IgE values from patients showed insignificant difference in non GM and GM maize extracts. Five maize sensitized cases, recognized same 7 protein fractions of 88-28 kD as IgE bindng in both GM and non-GM maize, signifying absence of variation. Four of the reported IgE binding proteins were also found to be stable by SGF. Conclusion Cry proteins did not indicate any significant similarity of >35% in allergen databases. Immunoassays also did not identify appreciable differences in endogenous IgE binding in GM and non GM maize. PMID:25706412

  8. A look at product development with genetically modified crops: examples from maize.

    PubMed

    Mumm, Rita H

    2013-09-04

    Plant breeding for crop genetic improvement involves the cycle of creating genetic diversity and exploiting that diversity to derive an improved cultivar with outstanding performance for specific traits of interest. Genetic modification through transformation essentially expands the genepool to facilitate access to genes otherwise not available through crossing. Transgenic events are defined by the DNA sequence that has been incorporated into the target genome and the specific point(s) of insertion. In the development of a new transgenic trait, typically many events are generated and evaluated with the aim of identifying one exhibiting consistent trait expression at or above specified thresholds, stable inheritance, and the absence of any negative effects. With transgenic traits for maize, once commercial candidates have been identified, these events are introgressed into elite lines, often through the use of molecular markers that can accelerate the breeding process and aid in producing a quality conversion. Converted elite lines are yield-tested to ensure performance equivalency with their unconverted counterparts. Finally, before commercial sale of seed, quality control monitoring is conducted to ensure event identity and purity and the absence of any unintended events. This monitoring complements other quality control measures to confirm seed viability and line/hybrid purity and uniformity in seed treatments, all in an effort to ensure customer satisfaction and to comply with governmental regulations. Thus, genetically modified (GM) cultivars are subject to significant testing and auditing prior to seed sale and distribution to farmers, more testing and auditing than with non-GM cultivars.

  9. Atlantic salmon (Salmo salar L.) parr fed genetically modified soybeans and maize: Histological, digestive, metabolic, and immunological investigations.

    PubMed

    Bakke-McKellep, A M; Sanden, M; Danieli, A; Acierno, R; Hemre, G-I; Maffia, M; Krogdahl, A

    2008-06-01

    Physiological and health related responses to dietary inclusion of genetically modified (GM) full-fat soybean meal (Roundup Ready; GM-soy) and maize (MON810 Bt-maize; GM-maize), as well as non-parental, untransformed lines (nGM-soy and nGM-maize D2), were evaluated in farmed Atlantic salmon (Salmo salar L.) parr during the first 8 months of feeding. Significant effects of dietary GM presence were only found in intestinal Na+-dependent d-glucose uptake and SGLT1 protein level in the region pyloric caeca in which the highest values were found in the GM-soy, intermediate in the nGM-soy, and lowest in the standard FM fed groups. Data from this study confirm that GM soybeans (RRS) and maize (MON810) at inclusion levels of about 6% appear to be as safe as commercially available nGM soy and maize in diets for Atlantic salmon parr. Results from studies with higher inclusion levels and with non-modified, isogenic or near-isogenic parental lines as control groups are pending.

  10. Comparative proteomic analysis of genetically modified maize grown under different agroecosystems conditions in Brazil

    PubMed Central

    2013-01-01

    Background Profiling technologies allow the simultaneous measurement and comparison of thousands of cell components without prior knowledge of their identity. In the present study, we used two-dimensional gel electrophoresis combined with mass spectrometry to evaluate protein expression of Brazilian genetically modified maize hybrid grown under different agroecosystems conditions. To this effect, leaf samples were subjected to comparative analysis using the near-isogenic non-GM hybrid as the comparator. Results In the first stage of the analysis, the main sources of variation in the dataset were identified by using Principal Components Analysis which correlated most of the variation to the different agroecosystems conditions. Comparative analysis within each field revealed a total of thirty two differentially expressed proteins between GM and non-GM samples that were identified and their molecular functions were mainly assigned to carbohydrate and energy metabolism, genetic information processing and stress response. Conclusions To the best of our knowledge this study represents the first evidence of protein identities with differentially expressed isoforms in Brazilian MON810 genetic background hybrid grown under field conditions. As global databases on outputs from “omics” analysis become available, these could provide a highly desirable benchmark for safety assessments. PMID:24304660

  11. Long term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize.

    PubMed

    Séralini, Gilles-Eric; Clair, Emilie; Mesnage, Robin; Gress, Steeve; Defarge, Nicolas; Malatesta, Manuela; Hennequin, Didier; de Vendômois, Joël Spiroux

    2012-11-01

    The health effects of a Roundup-tolerant genetically modified maize (from 11% in the diet), cultivated with or without Roundup, and Roundup alone (from 0.1 ppb in water), were studied 2 years in rats. In females, all treated groups died 2-3 times more than controls, and more rapidly. This difference was visible in 3 male groups fed GMOs. All results were hormone and sex dependent, and the pathological profiles were comparable. Females developed large mammary tumors almost always more often than and before controls, the pituitary was the second most disabled organ; the sex hormonal balance was modified by GMO and Roundup treatments. In treated males, liver congestions and necrosis were 2.5-5.5 times higher. This pathology was confirmed by optic and transmission electron microscopy. Marked and severe kidney nephropathies were also generally 1.3-2.3 greater. Males presented 4 times more large palpable tumors than controls which occurred up to 600 days earlier. Biochemistry data confirmed very significant kidney chronic deficiencies; for all treatments and both sexes, 76% of the altered parameters were kidney related. These results can be explained by the non linear endocrine-disrupting effects of Roundup, but also by the overexpression of the transgene in the GMO and its metabolic consequences.

  12. Establishment of quantitative analysis method for genetically modified maize using a reference plasmid and novel primers.

    PubMed

    Moon, Gi-Seong; Shin, Weon-Sun

    2012-12-01

    For the quantitative analysis of genetically modified (GM) maize in processed foods, primer sets and probes based on the 35S promoter (p35S), nopaline synthase terminator (tNOS), p35S-hsp70 intron, and zSSIIb gene encoding starch synthase II for intrinsic control were designed. Polymerase chain reaction (PCR) products (80~101 bp) were specifically amplified and the primer sets targeting the smaller regions (80 or 81 bp) were more sensitive than those targeting the larger regions (94 or 101 bp). Particularly, the primer set 35F1-R1 for p35S targeting 81 bp of sequence was even more sensitive than that targeting 101 bp of sequence by a 3-log scale. The target DNA fragments were also specifically amplified from all GM labeled food samples except for one item we tested when 35F1-R1 primer set was applied. A reference plasmid pGMmaize (3 kb) including the smaller PCR products for p35S, tNOS, p35S-hsp70 intron, and the zSSIIb gene was constructed for real-time PCR (RT-PCR). The linearity of standard curves was confirmed by using diluents ranging from 2×10(1)~10(5) copies of pGMmaize and the R(2) values ranged from 0.999~1.000. In the RT-PCR, the detection limit using the novel primer/probe sets was 5 pg of genomic DNA from MON810 line indicating that the primer sets targeting the smaller regions (80 or 81 bp) could be used for highly sensitive detection of foreign DNA fragments from GM maize in processed foods.

  13. Genotypic and Environmental Impact on Natural Variation of Nutrient Composition in 50 Non Genetically Modified Commercial Maize Hybrids in North America.

    PubMed

    Cong, Bin; Maxwell, Carl; Luck, Stanley; Vespestad, Deanne; Richard, Keith; Mickelson, James; Zhong, Cathy

    2015-06-10

    This study was designed to assess natural variation in composition and metabolites in 50 genetically diverse non genetically modified maize hybrids grown at six locations in North America. Results showed that levels of compositional components in maize forage were affected by environment more than genotype. Crude protein, all amino acids except lysine, manganese, and β-carotene in maize grain were affected by environment more than genotype; however, most proximates and fibers, all fatty acids, lysine, most minerals, vitamins, and secondary metabolites in maize grain were affected by genotype more than environment. A strong interaction between genotype and environment was seen for some analytes. The results could be used as reference values for future nutrient composition studies of genetically modified crops and to expand conventional compositional data sets. These results may be further used as a genetic basis for improvement of the nutritional value of maize grain by molecular breeding and biotechnology approaches.

  14. Detection of genetically modified maize in processed products, dry grains, and corn ears intended for fresh consumption in South Brazil.

    PubMed

    Oliveira, C A M; Kommers, C M; Lehmann, F K M; Fonseca, A S K; Ikuta, N; Lunge, V R

    2016-10-17

    Conventional and genetically modified (GM) maize cultivars have been widely planted in Brazil to produce grains for processed food, feed, or to be consumed fresh as corn ears. This study used real-time PCR to detect GM maize in processed products and fresh commercial corn ears produced in the last two years in South Brazil. Eighteen conventional and GM maize cultivars were obtained from seed production companies and 50 commercial samples (including canned corn, corn flour, dry grains, and fresh corn ears) were purchased in small local stores and supermarkets. All samples were analyzed by real time TaqMan PCR to detect one constitutive maize gene (hmg) and three genetic regions present in GM plants (p-35S promoter, major gene cry 1A.105, and t-Nos terminator). Each commercial sample was classified as conventional or GM based on the PCR results. PCR targeting the hmg gene generated positive results from all DNA samples, which were further tested with the GM targets. These targets were not detected in the five conventional maize cultivars, but were detected in the GM seeds hosting these fragments. Analysis of processed foods identified four cultivars as conventional and six as GM, which were mostly correctly labeled. Seven (53.8%) dry grain samples were classified as conventional, while six (46.2%) were classified as GM. Three (11.1%) corn ear samples were identified as conventional, and the remaining 24 (88.9%) were GM maize. These results demonstrate the high frequency of GM maize in processed products, including fresh corn ears intended for consumption in South Brazil.

  15. Decomposition dynamics and structural plant components of genetically modified Bt maize leaves do not differ from leaves of conventional hybrids.

    PubMed

    Zurbrügg, Corinne; Hönemann, Linda; Meissle, Michael; Romeis, Jörg; Nentwig, Wolfgang

    2010-04-01

    The cultivation of genetically modified Bt maize has raised environmental concerns, as large amounts of plant residues remain in the field and may negatively impact the soil ecosystem. In a field experiment, decomposition of leaf residues from three genetically modified (two expressing the Cry1Ab, one the Cry3Bb1 protein) and six non-transgenic hybrids (the three corresponding non-transformed near-isolines and three conventional hybrids) was investigated using litterbags. To elucidate the mechanisms that cause differences in plant decomposition, structural plant components (i.e., C:N ratio, lignin, cellulose, hemicellulose) were examined. Furthermore, Cry1Ab and Cry3Bb1 protein concentrations in maize leaf residues were measured from harvest to the next growing season. While leaf residue decomposition in transgenic and non-transgenic plants was similar, differences among conventional cultivars were evident. Similarly, plant components among conventional hybrids differed more than between transgenic and non-transgenic hybrids. Moreover, differences in senescent plant material collected directly from plants were larger than after exposure to soil for 5 months. While the concentration of Cry3Bb1 was higher in senescent maize leaves than that of Cry1Ab, degradation was faster, indicating that Cry3Bb1 has a shorter persistence in plant residues. As decomposition patterns of Bt-transgenic maize were shown to be well within the range of common conventional hybrids, there is no indication of ecologically relevant, adverse effects on the activity of the decomposer community.

  16. Sampling and modeling for the quantification of adventitious genetically modified presence in maize.

    PubMed

    Allnutt, Theodore Richard; Dwyer, Mark; McMillan, Jillian; Henry, Christine; Langrell, Stephen

    2008-05-14

    The coexistence of genetically modified (GM) and non-GM crops is an important economic and political issue in the European Union. We examined the GM content in non-GM maize crops in Spain in 2005. Both the standing crop and the harvest were tested, and the %GM DNA was quantified by real-time polymerase chain reaction. We compared the level of GM as a function of distance from known GM source fields in a 1.2 km2 landscape. The distribution of GM was compared to predictions from previous studies, and good agreement was found. Control and monitoring of adventitious GM presence in non-GM crops can only be achieved by fit-for-purpose sampling and testing schemes. We used a GM dispersal function to simulate non-GM crops in the studied zone and tested the accuracy of five different sampling schemes. Random sampling was found to be the most accurate and least susceptible to bias by GM spatial structure or gradients. Simulations showed that to achieve greater than 95% confidence in a GM labeling decision of a harvest (when treated as a single marketed lot), 34 samples would be needed when the harvest was outside 50% of the GM threshold value. The number of samples required increased rapidly as the harvest approached the GM threshold, implying that accurate labeling when the harvest is within +/-17% of the threshold may not be possible with high confidence.

  17. Resistance evolution to the first generation of genetically modified Diabrotica-active Bt-maize events by western corn rootworm: management and monitoring considerations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Western corn rootworm (Diabrotica virgifera virgifera; WCR) is a major coleopteran maize pest in North America and the EU, and has traditionally been managed through crop rotation and broad-spectrum soil insecticides. Genetically modified (GM) Bt-maize offers an additional means of control against W...

  18. Development and primary application of a fluorescent liquid bead array for the simultaneous identification of multiple genetically modified maize.

    PubMed

    Han, Xueqing; Wang, Huiyu; Chen, Hongjun; Mei, Lin; Wu, Shaoqiang; Jia, Guangle; Cheng, Tao; Zhu, Shuifang; Lin, Xiangmei

    2013-11-15

    An integration event-specific fluorescent liquid bead array was developed for the simultaneous identification of 10 genetically modified (GM) maize, including Bt176, Bt11, MON810, NK603, GA21, MON88017, MON89034, MIR604, T25 and MIR162, as well as one non-GM maize. The system comprised 11 specific oligonucleotide probes labeled with an amino group and coupled to fluorescence-encoded microspheres. To enable fluorescence detection, 11 pairs of primers labeled with biotin at the 5' ends were used. The hybridization signal of biotinylated PCR product to the probe-coupled microspheres was then detected. The limit of detection of this assay was 0.1% for GM maize, which is lower than the current labeling threshold levels enforced in the EU (0.9%). The results of the positive and negative controls were consistent with their expected situation, which showed that the method was highly specific. We detected GM maize in 20 of the 1370 commercial food samples tested, which were labeled as containing maize. The overall sensitivity, specificity, rapidity and high throughput capacity of this liquid chip system suggest that it could provide a significant improvement over current methods, and potentially offer an improved platform for further research into the detection of other GM plants.

  19. Maize Genetic Resources

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter describes the resources held at the Maize Genetics Cooperation • Stock Center in detail and also provides some information about the North Central Regional Plant Introduction Station (NCRPIS) in Ames, IA, Centro Internacional de Mejoramiento de Maiz y Trigo (CIMMYT) in Mexico, and the N...

  20. Absolute quantification of genetically modified MON810 maize (Zea mays L.) by digital polymerase chain reaction.

    PubMed

    Corbisier, Philippe; Bhat, Somanath; Partis, Lina; Xie, Vicki Rui Dan; Emslie, Kerry R

    2010-03-01

    Quantitative analysis of genetically modified (GM) foods requires estimation of the amount of the transgenic event relative to an endogenous gene. Regulatory authorities in the European Union (EU) have defined the labelling threshold for GM food on the copy number ratio between the transgenic event and an endogenous gene. Real-time polymerase chain reaction (PCR) is currently being used for quantification of GM organisms (GMOs). Limitations in real-time PCR applications to detect very low number of DNA targets has led to new developments such as the digital PCR (dPCR) which allows accurate measurement of DNA copies without the need for a reference calibrator. In this paper, the amount of maize MON810 and hmg copies present in a DNA extract from seed powders certified for their mass content and for their copy number ratio was measured by dPCR. The ratio of these absolute copy numbers determined by dPCR was found to be identical to the ratios measured by real-time quantitative PCR (qPCR) using a plasmid DNA calibrator. These results indicate that both methods could be applied to determine the copy number ratio in MON810. The reported values were in agreement with estimations from a model elaborated to convert mass fractions into copy number fractions in MON810 varieties. This model was challenged on two MON810 varieties used for the production of MON810 certified reference materials (CRMs) which differ in the parental origin of the introduced GM trait. We conclude that dPCR has a high metrological quality and can be used for certifying GM CRMs in terms of DNA copy number ratio.

  1. Short-term effects of different genetically modified maize varieties on arthropod food web properties: an experimental field assessment.

    PubMed

    Szénási, Ágnes; Pálinkás, Zoltán; Zalai, Mihály; Schmitz, Oswald J; Balog, Adalbert

    2014-06-17

    There is concern that genetically modified (GM) plants may have adverse affects on the arthropod biodiversity comprising agricultural landscapes. The present study report on a two year field experimental test of whether four different genotypic lines, some are novel with no previous field tests, of GM maize hybrids alter the structure of arthropod food webs that they harbour, relative to non-GM maize (control) that is widely used in agriculture. The different GM genotypes produced either Bt toxins, conferred glyphosate tolerance or a combination of the two traits. Quantitative food web analysis, based on short-term assessment assigning a total of 243,896 arthropod individuals collected from the treatments to their positions in food webs, revealed that complex and stable food webs persisted in each maize treatment. Moreover, food web structure remained relatively unchanged by the GM-genotype. The results suggest that at least in short-term period these particular GM maize genotypes will not have adverse effects on arthropod biota of agricultural landscapes.

  2. Temporal dynamics of microbial communities in the rhizosphere of two genetically modified (GM) maize hybrids in tropical agrosystems.

    PubMed

    Cotta, Simone Raposo; Dias, Armando Cavalcante Franco; Marriel, Ivanildo Evódio; Gomes, Eliane Aparecida; van Elsas, Jan Dirk; Seldin, Lucy

    2013-03-01

    The use of genetically modified (GM) plants still raises concerns about their environmental impact. The present study aimed to evaluate the possible effects of GM maize, in comparison to the parental line, on the structure and abundance of microbial communities in the rhizosphere. Moreover, the effect of soil type was addressed. For this purpose, the bacterial and fungal communities associated with the rhizosphere of GM plants were compared by culture-independent methodologies to the near-isogenic parental line. Two different soils and three stages of plant development in two different periods of the year were included. As evidenced by principal components analysis (PCA) of the PCR-DGGE profiles of evaluated community, clear differences occurred in these rhizosphere communities between soils and the periods of the year that maize was cultivated. However, there were no discernible effects of the GM lines as compared to the parental line. For all microbial communities evaluated, soil type and the period of the year that the maize was cultivated were the main factors that influenced their structures. No differences were observed in the abundances of total bacteria between the rhizospheres of GM and parental plant lines.

  3. High-throughput sequence-based analysis of the intestinal microbiota of weanling pigs fed genetically modified MON810 maize expressing Bacillus thuringiensis Cry1Ab (Bt maize) for 31 days.

    PubMed

    Buzoianu, Stefan G; Walsh, Maria C; Rea, Mary C; O'Sullivan, Orla; Cotter, Paul D; Ross, R Paul; Gardiner, Gillian E; Lawlor, Peadar G

    2012-06-01

    The objective of this study was to investigate if feeding genetically modified (GM) MON810 maize expressing the Bacillus thuringiensis insecticidal protein (Bt maize) had any effects on the porcine intestinal microbiota. Eighteen pigs were weaned at ~28 days and, following a 6-day acclimatization period, were assigned to diets containing either GM (Bt MON810) maize or non-GM isogenic parent line maize for 31 days (n = 9/treatment). Effects on the porcine intestinal microbiota were assessed through culture-dependent and -independent approaches. Fecal, cecal, and ileal counts of total anaerobes, Enterobacteriaceae, and Lactobacillus were not significantly different between pigs fed the isogenic or Bt maize-based diets. Furthermore, high-throughput 16S rRNA gene sequencing revealed few differences in the compositions of the cecal microbiotas. The only differences were that pigs fed the Bt maize diet had higher cecal abundance of Enterococcaceae (0.06 versus 0%; P < 0.05), Erysipelotrichaceae (1.28 versus 1.17%; P < 0.05), and Bifidobacterium (0.04 versus 0%; P < 0.05) and lower abundance of Blautia (0.23 versus 0.40%; P < 0.05) than pigs fed the isogenic maize diet. A lower enzyme-resistant starch content in the Bt maize, which is most likely a result of normal variation and not due to the genetic modification, may account for some of the differences observed within the cecal microbiotas. These results indicate that Bt maize is well tolerated by the porcine intestinal microbiota and provide additional data for safety assessment of Bt maize. Furthermore, these data can potentially be extrapolated to humans, considering the suitability of pigs as a human model.

  4. Detection of nonauthorized genetically modified organisms using differential quantitative polymerase chain reaction: application to 35S in maize.

    PubMed

    Cankar, Katarina; Chauvensy-Ancel, Valérie; Fortabat, Marie-Noelle; Gruden, Kristina; Kobilinsky, André; Zel, Jana; Bertheau, Yves

    2008-05-15

    Detection of nonauthorized genetically modified organisms (GMOs) has always presented an analytical challenge because the complete sequence data needed to detect them are generally unavailable although sequence similarity to known GMOs can be expected. A new approach, differential quantitative polymerase chain reaction (PCR), for detection of nonauthorized GMOs is presented here. This method is based on the presence of several common elements (e.g., promoter, genes of interest) in different GMOs. A statistical model was developed to study the difference between the number of molecules of such a common sequence and the number of molecules identifying the approved GMO (as determined by border-fragment-based PCR) and the donor organism of the common sequence. When this difference differs statistically from zero, the presence of a nonauthorized GMO can be inferred. The interest and scope of such an approach were tested on a case study of different proportions of genetically modified maize events, with the P35S promoter as the Cauliflower Mosaic Virus common sequence. The presence of a nonauthorized GMO was successfully detected in the mixtures analyzed and in the presence of (donor organism of P35S promoter). This method could be easily transposed to other common GMO sequences and other species and is applicable to other detection areas such as microbiology.

  5. Development and validation of an event-specific quantitative PCR method for genetically modified maize MIR162.

    PubMed

    Takabatake, Reona; Masubuchi, Tomoko; Futo, Satoshi; Minegishi, Yasutaka; Noguchi, Akio; Kondo, Kazunari; Teshima, Reiko; Kurashima, Takeyo; Mano, Junichi; Kitta, Kazumi

    2014-01-01

    A novel real-time PCR-based analytical method was developed for the event-specific quantification of a genetically modified (GM) maize event, MIR162. We first prepared a standard plasmid for MIR162 quantification. The conversion factor (Cf) required to calculate the genetically modified organism (GMO) amount was empirically determined for two real-time PCR instruments, the Applied Biosystems 7900HT (ABI7900) and the Applied Biosystems 7500 (ABI7500) for which the determined Cf values were 0.697 and 0.635, respectively. To validate the developed method, a blind test was carried out in an interlaboratory study. The trueness and precision were evaluated as the bias and reproducibility of relative standard deviation (RSDr). The determined biases were less than 25% and the RSDr values were less than 20% at all evaluated concentrations. These results suggested that the limit of quantitation of the method was 0.5%, and that the developed method would thus be suitable for practical analyses for the detection and quantification of MIR162.

  6. Randomly detected genetically modified (GM) maize (Zea mays L.) near a transport route revealed a fragile 45S rDNA phenotype.

    PubMed

    Waminal, Nomar Espinosa; Ryu, Ki Hyun; Choi, Sun-Hee; Kim, Hyun Hee

    2013-01-01

    Monitoring of genetically modified (GM) crops has been emphasized to prevent their potential effects on the environment and human health. Monitoring of the inadvertent dispersal of transgenic maize in several fields and transport routes in Korea was carried out by qualitative multiplex PCR, and molecular analyses were conducted to identify the events of the collected GM maize. Cytogenetic investigations through fluorescence in situ hybridization (FISH) of the GM maize were performed to check for possible changes in the 45S rDNA cluster because this cluster was reported to be sensitive to replication and transcription stress. Three GM maize kernels were collected from a transport route near Incheon port, Korea, and each was found to contain NK603, stacked MON863 x NK603, and stacked NK603 x MON810 inserts, respectively. Cytogenetic analysis of the GM maize containing the stacked NK603 x MON810 insert revealed two normal compact 5S rDNA signals, but the 45S rDNA showed a fragile phenotype, demonstrating a "beads-on-a-string" fragmentation pattern, which seems to be a consequence of genetic modification. Implications of the 45S rDNA cluster fragility in GM maize are also discussed.

  7. Development and validation of event-specific quantitative PCR method for genetically modified maize MIR604.

    PubMed

    Mano, Junichi; Furui, Satoshi; Takashima, Kaori; Koiwa, Tomohiro; Futo, Satoshi; Minegishi, Yasutaka; Akiyama, Hiroshi; Teshima, Reiko; Kurashima, Takeyo; Takabatake, Reona; Kitta, Kazumi

    2012-01-01

    A GM maize event, MIR604, has been widely distributed and an analytical method to quantify its content is required to monitor the validity of food labeling. Here we report a novel real-time PCR-based quantitation method for MIR604 maize. We developed real-time PCR assays specific for MIR604 using event-specific primers designed by the trait developer, and for maize endogenous starch synthase IIb gene (SSIIb). Then, we determined the conversion factor, which is required to calculate the weight-based GM maize content from the copy number ratio of MIR604-specific DNA to the endogenous reference DNA. Finally, to validate the developed method, an interlaboratory collaborative trial according to the internationally harmonized guidelines was performed with blind samples containing MIR604 at the mixing levels of 0, 0.5, 1.0, 5.0 and 10.0%. The reproducibility (RSDr) of the developed method was evaluated to be less than 25%. The limit of quantitation of the method was estimated to be 0.5% based on the ISO 24276 guideline. These results suggested that the developed method would be suitable for practical quantitative analyses of MIR604 maize.

  8. Multiplex quantification of 12 European Union authorized genetically modified maize lines with droplet digital polymerase chain reaction.

    PubMed

    Dobnik, David; Spilsberg, Bjørn; Bogožalec Košir, Alexandra; Holst-Jensen, Arne; Žel, Jana

    2015-08-18

    Presence of genetically modified organisms (GMO) in food and feed products is regulated in many countries. The European Union (EU) has implemented a threshold for labeling of products containing more than 0.9% of authorized GMOs per ingredient. As the number of GMOs has increased over time, standard-curve based simplex quantitative polymerase chain reaction (qPCR) analyses are no longer sufficiently cost-effective, despite widespread use of initial PCR based screenings. Newly developed GMO detection methods, also multiplex methods, are mostly focused on screening and detection but not quantification. On the basis of droplet digital PCR (ddPCR) technology, multiplex assays for quantification of all 12 EU authorized GM maize lines (per April first 2015) were developed. Because of high sequence similarity of some of the 12 GM targets, two separate multiplex assays were needed. In both assays (4-plex and 10-plex), the transgenes were labeled with one fluorescence reporter and the endogene with another (GMO concentration = transgene/endogene ratio). It was shown that both multiplex assays produce specific results and that performance parameters such as limit of quantification, repeatability, and trueness comply with international recommendations for GMO quantification methods. Moreover, for samples containing GMOs, the throughput and cost-effectiveness is significantly improved compared to qPCR. Thus, it was concluded that the multiplex ddPCR assays could be applied for routine quantification of 12 EU authorized GM maize lines. In case of new authorizations, the events can easily be added to the existing multiplex assays. The presented principle of quantitative multiplexing can be applied to any other domain.

  9. [Development and validation of event-specific quantitative PCR method for genetically modified maize LY038].

    PubMed

    Mano, Junichi; Masubuchi, Tomoko; Hatano, Shuko; Futo, Satoshi; Koiwa, Tomohiro; Minegishi, Yasutaka; Noguchi, Akio; Kondo, Kazunari; Akiyama, Hiroshi; Teshima, Reiko; Kurashima, Takeyo; Takabatake, Reona; Kitta, Kazumi

    2013-01-01

    In this article, we report a novel real-time PCR-based analytical method for quantitation of the GM maize event LY038. We designed LY038-specific and maize endogenous reference DNA-specific PCR amplifications. After confirming the specificity and linearity of the LY038-specific PCR amplification, we determined the conversion factor required to calculate the weight-based content of GM organism (GMO) in a multilaboratory evaluation. Finally, in order to validate the developed method, an interlaboratory collaborative trial according to the internationally harmonized guidelines was performed with blind DNA samples containing LY038 at the mixing levels of 0, 0.5, 1.0, 5.0 and 10.0%. The precision of the method was evaluated as the RSD of reproducibility (RSDR), and the values obtained were all less than 25%. The limit of quantitation of the method was judged to be 0.5% based on the definition of ISO 24276 guideline. The results from the collaborative trial suggested that the developed quantitative method would be suitable for practical testing of LY038 maize.

  10. A new PCR-CGE (size and color) method for simultaneous detection of genetically modified maize events.

    PubMed

    Nadal, Anna; Coll, Anna; La Paz, Jose-Luis; Esteve, Teresa; Pla, Maria

    2006-10-01

    We present a novel multiplex PCR assay for simultaneous detection of multiple transgenic events in maize. Initially, five PCR primers pairs specific to events Bt11, GA21, MON810, and NK603, and Zea mays L. (alcohol dehydrogenase) were included. The event specificity was based on amplification of transgene/plant genome flanking regions, i.e., the same targets as for validated real-time PCR assays. These short and similarly sized amplicons were selected to achieve high and similar amplification efficiency for all targets; however, its unambiguous identification was a technical challenge. We achieved a clear distinction by a novel CGE approach that combined the identification by size and color (CGE-SC). In one single step, all five targets were amplified and specifically labeled with three different fluorescent dyes. The assay was specific and displayed an LOD of 0.1% of each genetically modified organism (GMO). Therefore, it was adequate to fulfill legal thresholds established, e.g., in the European Union. Our CGE-SC based strategy in combination with an adequate labeling design has the potential to simultaneously detect higher numbers of targets. As an example, we present the detection of up to eight targets in a single run. Multiplex PCR-CGE-SC only requires a conventional sequencer device and enables automation and high throughput. In addition, it proved to be transferable to a different laboratory. The number of authorized GMO events is rapidly growing; and the acreage of genetically modified (GM) varieties cultivated and commercialized worldwide is rapidly increasing. In this context, our multiplex PCR-CGE-SC can be suitable for screening GM contents in food.

  11. Interlaboratory validation of quantitative duplex real-time PCR method for screening analysis of genetically modified maize.

    PubMed

    Takabatake, Reona; Koiwa, Tomohiro; Kasahara, Masaki; Takashima, Kaori; Futo, Satoshi; Minegishi, Yasutaka; Akiyama, Hiroshi; Teshima, Reiko; Oguchi, Taichi; Mano, Junichi; Furui, Satoshi; Kitta, Kazumi

    2011-01-01

    To reduce the cost and time required to routinely perform the genetically modified organism (GMO) test, we developed a duplex quantitative real-time PCR method for a screening analysis simultaneously targeting an event-specific segment for GA21 and Cauliflower Mosaic Virus 35S promoter (P35S) segment [Oguchi et al., J. Food Hyg. Soc. Japan, 50, 117-125 (2009)]. To confirm the validity of the method, an interlaboratory collaborative study was conducted. In the collaborative study, conversion factors (Cfs), which are required to calculate the GMO amount (%), were first determined for two real-time PCR instruments, the ABI PRISM 7900HT and the ABI PRISM 7500. A blind test was then conducted. The limit of quantitation for both GA21 and P35S was estimated to be 0.5% or less. The trueness and precision were evaluated as the bias and reproducibility of the relative standard deviation (RSD(R)). The determined bias and RSD(R) were each less than 25%. We believe the developed method would be useful for the practical screening analysis of GM maize.

  12. Direct extraction of genomic DNA from maize with aqueous ionic liquid buffer systems for applications in genetically modified organisms analysis.

    PubMed

    Gonzalez García, Eric; Ressmann, Anna K; Gaertner, Peter; Zirbs, Ronald; Mach, Robert L; Krska, Rudolf; Bica, Katharina; Brunner, Kurt

    2014-12-01

    To date, the extraction of genomic DNA is considered a bottleneck in the process of genetically modified organisms (GMOs) detection. Conventional DNA isolation methods are associated with long extraction times and multiple pipetting and centrifugation steps, which makes the entire procedure not only tedious and complicated but also prone to sample cross-contamination. In recent times, ionic liquids have emerged as innovative solvents for biomass processing, due to their outstanding properties for dissolution of biomass and biopolymers. In this study, a novel, easily applicable, and time-efficient method for the direct extraction of genomic DNA from biomass based on aqueous-ionic liquid solutions was developed. The straightforward protocol relies on extraction of maize in a 10 % solution of ionic liquids in aqueous phosphate buffer for 5 min at room temperature, followed by a denaturation step at 95 °C for 10 min and a simple filtration to remove residual biopolymers. A set of 22 ionic liquids was tested in a buffer system and 1-ethyl-3-methylimidazolium dimethylphosphate, as well as the environmentally benign choline formate, were identified as ideal candidates. With this strategy, the quality of the genomic DNA extracted was significantly improved and the extraction protocol was notably simplified compared with a well-established method.

  13. Pepsin degradation of Cry1A(b) protein purified from genetically modified maize (Zea mays).

    PubMed

    de Luis, Ruth; Lavilla, María; Sánchez, Lourdes; Calvo, Miguel; Pérez, María D

    2010-02-24

    The aim of this work was to study the in vitro digestion of Cry1A(b) protein by pepsin. To perform this work, a protein fraction purified from transgenic maize by immunoadsorption was employed. The undigested fraction showed several bands of molecular weight ranging between 14 and 70 kDa when assayed by SDS-PAGE. These bands were identified as corresponding to Cry1A(b) protein by immunochemical techniques and mass spectrometry. The rate of degradation of the purified fraction by pepsin estimated by ELISA was found to be about 75% within 30 min, and the protein concentration remained constant up to 4 h. In all treated samples, the full-length protein and fragments present in Cry1A(b) fraction were absent and peptides of less than 8.5 kDa were mainly found by SDS-PAGE and mass spectrometry. These peptides did not react with antiserum against Cry1A(b) protein by Western blotting. These results suggest that Cry1A(b) fraction purified from transgenic maize is rapidly and extensively degraded by pepsin, giving peptides of low molecular mass.

  14. Maize Genetics and Genomics Database

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This report is provided each year to our stakeholders in the maize genetic community. In this report, we describe the five-year plan for MaizeGDB reviewed in early 2008 by the USDA-ARS peer review process and which was developed with inputs from our Working Group and the Allerton 2007 Report (MNL 82...

  15. A single nucleotide polymorphism (SNP839) in the adh1 reference gene affects the quantitation of genetically modified maize (Zea mays L.).

    PubMed

    Broothaerts, Wim; Corbisier, Philippe; Schimmel, Heinz; Trapmann, Stefanie; Vincent, Sandra; Emons, Hendrik

    2008-10-08

    The real-time PCR methods recommended in the European Union for the quantitation of genetically modified (GM) maize events NK603, GA21, and MON 863 measure the number of copies of the GM event in relation to those of the maize-specific adh1 reference gene. The study reported here revealed that the targeted 70 base pair adh1 region exhibits a single nucleotide polymorphism (SNP839) that hampers the binding of the reverse primer used in the adh1 detection method. Partial fragments of the adh1-A and adh1-F allele were cloned. By allele-specific real-time PCR, it was shown that SNP839 corresponds to a common allelic polymorphism in maize. As a result, the quantitation of the GM maize events mentioned is positively or negatively biased, depending on the adh1 genotype of sample and calibrant. Therefore, it is proposed to revise the quantitative detection methods for NK603, GA21, and MON 863 maize.

  16. Validation of real-time PCR analyses for line-specific quantitation of genetically modified maize and soybean using new reference molecules.

    PubMed

    Shindo, Yoichiro; Kuribara, Hideo; Matsuoka, Takeshi; Futo, Satoshi; Sawada, Chihiro; Shono, Jinji; Akiyama, Hiroshi; Goda, Yukihiro; Toyoda, Masatake; Hino, Akihiro

    2002-01-01

    Novel analytical methods based on real-time quantitative polymerase chain reactions by use of new reference molecules were validated in interlaboratory studies for the quantitation of genetically modified (GM) maize and soy. More than 13 laboratories from Japan, Korea, and the United States participated in the studies. The interlaboratory studies included 2 separate stages: (1) measurement tests of coefficient values, the ratio of recombinant DNA (r-DNA) sequence, and endogenous DNA sequence in the seeds of GM maize and GM soy; and (2) blind tests with 6 pairs of maize and soy samples, including different levels of GM maize or GM soy. Test results showed that the methods are applicable to the specific quantitation of the 5 lines of GM maize and one line of GM soy. After statistical treatment to remove outliers, the repeatability and reproducibility of these methods at a level of 5.0% were <13.7 and 15.9%, respectively. The quantitation limits of the methods were 0.50% for Bt11, T25, and MON810, and 0.10% for GA21, Event176, and Roundup Ready soy. The results of blind tests showed that the numerical information obtained from these methods will contribute to practical analyses for labeling systems of GM crops.

  17. Simultaneous detection of eight genetically modified maize lines using a combination of event- and construct-specific multiplex-PCR technique.

    PubMed

    Shrestha, Hari K; Hwu, Kae-Kang; Wang, Shu-Jen; Liu, Li-Fei; Chang, Men-Chi

    2008-10-08

    To fulfill labeling and traceability requirement of genetically modified (GM) maize for trade and regulation, it is essential to develop an event-specific detection method for monitoring the presence of transgenes. In pursuit of this purpose, we systematically optimized and established a combined event- and construct-specific multiplex polymerase chain reaction (mPCR) technique for simultaneous detection of 8 GM maize lines. Altogether 9 sets of primers were designed, including six that were event-specific for Event176, Bt11, TC1507, NK603, MON863, and Mon810; two that were construct-specific for T25 and GA21, and one for an endogenous zein gene. The transgene in each GM maize line and the endogenous zein gene could be clearly detected and distinguished according to the different sizes of PCR amplicons. The limit of detection (LOD) was approximately 0.25% (v/v), although the detection can be as sensitive as 0.1% as demonstrated by the International Seed Testing Association (ISTA) proficiency test. This study further improves the current PCR-based detection method for GM maize. The method can be used in an easy, sensitive, and cost and time effective way for the identification and quality screening of a specific GM maize line.

  18. Event specific qualitative and quantitative polymerase chain reaction detection of genetically modified MON863 maize based on the 5'-transgene integration sequence.

    PubMed

    Yang, Litao; Xu, Songci; Pan, Aihu; Yin, Changsong; Zhang, Kewei; Wang, Zhenying; Zhou, Zhigang; Zhang, Dabing

    2005-11-30

    Because of the genetically modified organisms (GMOs) labeling policies issued in many countries and areas, polymerase chain reaction (PCR) methods were developed for the execution of GMO labeling policies, such as screening, gene specific, construct specific, and event specific PCR detection methods, which have become a mainstay of GMOs detection. The event specific PCR detection method is the primary trend in GMOs detection because of its high specificity based on the flanking sequence of the exogenous integrant. This genetically modified maize, MON863, contains a Cry3Bb1 coding sequence that produces a protein with enhanced insecticidal activity against the coleopteran pest, corn rootworm. In this study, the 5'-integration junction sequence between the host plant DNA and the integrated gene construct of the genetically modified maize MON863 was revealed by means of thermal asymmetric interlaced-PCR, and the specific PCR primers and TaqMan probe were designed based upon the revealed 5'-integration junction sequence; the conventional qualitative PCR and quantitative TaqMan real-time PCR detection methods employing these primers and probes were successfully developed. In conventional qualitative PCR assay, the limit of detection (LOD) was 0.1% for MON863 in 100 ng of maize genomic DNA for one reaction. In the quantitative TaqMan real-time PCR assay, the LOD and the limit of quantification were eight and 80 haploid genome copies, respectively. In addition, three mixed maize samples with known MON863 contents were detected using the established real-time PCR systems, and the ideal results indicated that the established event specific real-time PCR detection systems were reliable, sensitive, and accurate.

  19. Ninety-day oral toxicity studies on two genetically modified maize MON810 varieties in Wistar Han RCC rats (EU 7th Framework Programme project GRACE).

    PubMed

    Zeljenková, Dagmar; Ambrušová, Katarína; Bartušová, Mária; Kebis, Anton; Kovrižnych, Jevgenij; Krivošíková, Zora; Kuricová, Miroslava; Líšková, Aurélia; Rollerová, Eva; Spustová, Viera; Szabová, Elena; Tulinská, Jana; Wimmerová, Soňa; Levkut, Mikuláš; Révajová, Viera; Ševčíková, Zuzana; Schmidt, Kerstin; Schmidtke, Jörg; La Paz, Jose Luis; Corujo, Maria; Pla, Maria; Kleter, Gijs A; Kok, Esther J; Sharbati, Jutta; Hanisch, Carlos; Einspanier, Ralf; Adel-Patient, Karine; Wal, Jean-Michel; Spök, Armin; Pöting, Annette; Kohl, Christian; Wilhelm, Ralf; Schiemann, Joachim; Steinberg, Pablo

    2014-12-01

    The GMO Risk Assessment and Communication of Evidence (GRACE; www.grace-fp7.eu ) project is funded by the European Commission within the 7th Framework Programme. A key objective of GRACE is to conduct 90-day animal feeding trials, animal studies with an extended time frame as well as analytical, in vitro and in silico studies on genetically modified (GM) maize in order to comparatively evaluate their use in GM plant risk assessment. In the present study, the results of two 90-day feeding trials with two different GM maize MON810 varieties, their near-isogenic non-GM varieties and four additional conventional maize varieties are presented. The feeding trials were performed by taking into account the guidance for such studies published by the EFSA Scientific Committee in 2011 and the OECD Test Guideline 408. The results obtained show that the MON810 maize at a level of up to 33 % in the diet did not induce adverse effects in male and female Wistar Han RCC rats after subchronic exposure, independently of the two different genetic backgrounds of the event.

  20. Selection of Suitable DNA Extraction Methods for Genetically Modified Maize 3272, and Development and Evaluation of an Event-Specific Quantitative PCR Method for 3272.

    PubMed

    Takabatake, Reona; Masubuchi, Tomoko; Futo, Satoshi; Minegishi, Yasutaka; Noguchi, Akio; Kondo, Kazunari; Teshima, Reiko; Kurashima, Takeyo; Mano, Junichi; Kitta, Kazumi

    2016-01-01

    A novel real-time PCR-based analytical method was developed for the event-specific quantification of a genetically modified (GM) maize, 3272. We first attempted to obtain genome DNA from this maize using a DNeasy Plant Maxi kit and a DNeasy Plant Mini kit, which have been widely utilized in our previous studies, but DNA extraction yields from 3272 were markedly lower than those from non-GM maize seeds. However, lowering of DNA extraction yields was not observed with GM quicker or Genomic-tip 20/G. We chose GM quicker for evaluation of the quantitative method. We prepared a standard plasmid for 3272 quantification. The conversion factor (Cf), which is required to calculate the amount of a genetically modified organism (GMO), was experimentally determined for two real-time PCR instruments, the Applied Biosystems 7900HT (the ABI 7900) and the Applied Biosystems 7500 (the ABI7500). The determined Cf values were 0.60 and 0.59 for the ABI 7900 and the ABI 7500, respectively. To evaluate the developed method, a blind test was conducted as part of an interlaboratory study. The trueness and precision were evaluated as the bias and reproducibility of the relative standard deviation (RSDr). The determined values were similar to those in our previous validation studies. The limit of quantitation for the method was estimated to be 0.5% or less, and we concluded that the developed method would be suitable and practical for detection and quantification of 3272.

  1. Resistance evolution to the first generation of genetically modified Diabrotica-active Bt-maize events by western corn rootworm: management and monitoring considerations.

    PubMed

    Devos, Yann; Meihls, Lisa N; Kiss, József; Hibbard, Bruce E

    2013-04-01

    Western corn rootworm (Diabrotica virgifera virgifera; WCR) is a major coleopteran maize pest in North America and the EU, and has traditionally been managed through crop rotation and broad-spectrum soil insecticides. Genetically modified Bt-maize offers an additional management tool for WCR and has been valuable in reducing insecticide use and increasing farm income. A concern is that the widespread, repeated, and exclusive deployment of the same Bt-maize transformation event will result in the rapid evolution of resistance in WCR. This publication explores the potential of WCR to evolve resistance to plant-produced Bt-toxins from the first generation of Diabrotica-active Bt-maize events (MON 863 and MON 88017, DAS-59122-7 and MIR604), and whether currently implemented risk management strategies to delay and monitor resistance evolution are appropriate. In twelve of the twelve artificial selection experiments reported, resistant WCR populations were yielded rapidly. Field-selected resistance of WCR to Cry3Bb1 is documented in some US maize growing areas, where an increasing number of cases of unexpected damage of WCR larvae to Bt-maize MON 88017 has been reported. Currently implemented insect resistance management measures for Bt-crops usually rely on the high dose/refuge (HDR) strategy. Evidence (including laboratory, greenhouse and field data) indicates that several conditions contributing to the success of the HDR strategy may not be met for the first generation of Bt-maize events and WCR: (1) the Bt-toxins are expressed heterogeneously at a low-to-moderate dose in roots; (2) resistance alleles may be present at a higher frequency than initially assumed; (3) WCR may mate in a non-random manner; (4) resistance traits could have non-recessive inheritance; and (5) fitness costs may not necessarily be associated with resistance evolution. However, caution must be exercised when extrapolating laboratory and greenhouse results to field conditions. Model predictions

  2. Genetically modified feeds in animal nutrition. 2nd communication: glufosinate tolerant sugar beets (roots and silage) and maize grains for ruminants and pigs.

    PubMed

    Böhme, H; Aulrich, K; Daenicke, R; Flachowsky, G

    2001-01-01

    To analyse substantial equivalence of genetically modified sugar-beets and maize, in which the glufosinate-tolerant (Pat) gene is inserted, crude nutrients, the amino acid and the fatty acid profiles as well as the composition of the NDF-fraction of maize grains were determined and compared with those of the corresponding non-transgenic cultivars. Due to the genetic manipulation differences in crude nutrient contents including sugar and starch were not detected. The amino acid profile of maize grains was analysed to be the same. Fatty acid profile and composition of cell wall constituents did not show any influences as well. Digestibility of Pat-sugar-beets and maize grains for pigs did not demonstrate meaningful differences as compared to the corresponding non-transgenic cultivars. Digestibility of sugar-beet roots and sugar-beet top silage for ruminants proved to be also in the scope of natural variance. As the digestibility of the macro nutrients remained unaffected, the Pat-gene introduction into both crops did not show an influence on the energetic feeding value. For pigs the ME-content of Pat-sugar-beets was determined to be 14.1 MJ/kg DM versus 13.7 MJ of the non-transgenic cultivars. ME-content of Pat-maize grains was 16.0 MJ/kg DM versus 15.8 MJ for controls. For ruminants the feeding value of Pat-sugar-beets was found to be 8.5 MJ NEL/kg DM or 13.2 MJ ME/kg DM, regardless of whether the Pat-gene was inserted or not. The corresponding energy values of sugar-beet top silage ranged between 5.2 and 5.5 MJ NEL/kg DM or 8.6 and 9.1 MJ ME/kg DM, with differences considered in the biological range.

  3. Interlaboratory study of DNA extraction from multiple ground samples, multiplex real-time PCR, and multiplex qualitative PCR for individual kernel detection system of genetically modified maize.

    PubMed

    Akiyama, Hiroshi; Sakata, Kozue; Makiyma, Daiki; Nakamura, Kosuke; Teshima, Reiko; Nakashima, Akie; Ogawa, Asako; Yamagishi, Toru; Futo, Satoshi; Oguchi, Taichi; Mano, Junichi; Kitta, Kazumi

    2011-01-01

    In many countries, the labeling of grains, feed, and foodstuff is mandatory if the genetically modified (GM) organism content exceeds a certain level of approved GM varieties. We previously developed an individual kernel detection system consisting of grinding individual kernels, DNA extraction from the individually ground kernels, GM detection using multiplex real-time PCR, and GM event detection using multiplex qualitative PCR to analyze the precise commingling level and varieties of GM maize in real sample grains. We performed the interlaboratory study of the DNA extraction with multiple ground samples, multiplex real-time PCR detection, and multiplex qualitative PCR detection to evaluate its applicability, practicality, and ruggedness for the individual kernel detection system of GM maize. DNA extraction with multiple ground samples, multiplex real-time PCR, and multiplex qualitative PCR were evaluated by five laboratories in Japan, and all results from these laboratories were consistent with the expected results in terms of the commingling level and event analysis. Thus, the DNA extraction with multiple ground samples, multiplex real-time PCR, and multiplex qualitative PCR for the individual kernel detection system is applicable and practicable in a laboratory to regulate the commingling level of GM maize grain for GM samples, including stacked GM maize.

  4. One-year oral toxicity study on a genetically modified maize MON810 variety in Wistar Han RCC rats (EU 7th Framework Programme project GRACE).

    PubMed

    Zeljenková, Dagmar; Aláčová, Radka; Ondrejková, Júlia; Ambrušová, Katarína; Bartušová, Mária; Kebis, Anton; Kovrižnych, Jevgenij; Rollerová, Eva; Szabová, Elena; Wimmerová, Soňa; Černák, Martin; Krivošíková, Zora; Kuricová, Miroslava; Líšková, Aurélia; Spustová, Viera; Tulinská, Jana; Levkut, Mikuláš; Révajová, Viera; Ševčíková, Zuzana; Schmidt, Kerstin; Schmidtke, Jörg; Schmidt, Paul; La Paz, Jose Luis; Corujo, Maria; Pla, Maria; Kleter, Gijs A; Kok, Esther J; Sharbati, Jutta; Bohmer, Marc; Bohmer, Nils; Einspanier, Ralf; Adel-Patient, Karine; Spök, Armin; Pöting, Annette; Kohl, Christian; Wilhelm, Ralf; Schiemann, Joachim; Steinberg, Pablo

    2016-10-01

    The GRACE (GMO Risk Assessment and Communication of Evidence; www.grace-fp7.eu ) project was funded by the European Commission within the 7th Framework Programme. A key objective of GRACE was to conduct 90-day animal feeding trials, animal studies with an extended time frame as well as analytical, in vitro and in silico studies on genetically modified (GM) maize in order to comparatively evaluate their use in GM plant risk assessment. In the present study, the results of a 1-year feeding trial with a GM maize MON810 variety, its near-isogenic non-GM comparator and an additional conventional maize variety are presented. The feeding trials were performed by taking into account the guidance for such studies published by the EFSA Scientific Committee in 2011 and the OECD Test Guideline 452. The results obtained show that the MON810 maize at a level of up to 33 % in the diet did not induce adverse effects in male and female Wistar Han RCC rats after a chronic exposure.

  5. Effects of trans-acting Genetic Modifiers on Meiotic Recombination Across the a1–sh2 Interval of Maize

    PubMed Central

    Yandeau-Nelson, Marna D.; Nikolau, Basil J.; Schnable, Patrick S.

    2006-01-01

    Meiotic recombination rates are potentially affected by cis- and trans-acting factors, i.e., genotype-specific modifiers that do or do not reside in the recombining interval, respectively. Effects of trans modifiers on recombination across the ∼140-kb maize a1–sh2 interval of chromosome 3L were studied in the absence of polymorphic cis factors in three genetically diverse backgrounds into which a sequence-identical a1–sh2 interval had been introgressed. Genetic distances across a1–sh2 varied twofold among genetic backgrounds. Although the existence of regions exhibiting high and low rates of recombination (hot and cold spots, respectively) was conserved across backgrounds, the absolute rates of recombination in these sequence-identical regions differed significantly among backgrounds. In addition, an intergenic hot spot had a higher rate of recombination as compared to the genome average rate of recombination in one background and not in another. Recombination rates across two genetic intervals on chromosome 1 did not exhibit the same relationships among backgrounds as was observed in a1–sh2. This suggests that at least some detected trans-acting factors do not equally affect recombination across the genome. This study establishes that trans modifier(s) polymorphic among genetic backgrounds can increase and decrease recombination in both genic and intergenic regions over relatively small genetic and physical intervals. PMID:16816431

  6. Interlaboratory transfer of a PCR multiplex method for simultaneous detection of four genetically modified maize lines: Bt11, MON810, T25, and GA21.

    PubMed

    Hernández, Marta; Rodríguez-Lázaro, David; Zhang, David; Esteve, Teresa; Pla, Maria; Prat, Salomé

    2005-05-04

    The number of cultured hectares and commercialized genetically modified organisms (GMOs) has increased exponentially in the past 9 years. Governments in many countries have established a policy of labeling all food and feed containing or produced by GMOs. Consequently, versatile, laboratory-transferable GMO detection methods are in increasing demand. Here, we describe a qualitative PCR-based multiplex method for simultaneous detection and identification of four genetically modified maize lines: Bt11, MON810, T25, and GA21. The described system is based on the use of five primers directed to specific sequences in these insertion events. Primers were used in a single optimized multiplex PCR reaction, and sequences of the amplified fragments are reported. The assay allows amplification of the MON810 event from the 35S promoter to the hsp intron yielding a 468 bp amplicon. Amplification of the Bt11 and T25 events from the 35S promoter to the PAT gene yielded two different amplicons of 280 and 177 bp, respectively, whereas amplification of the 5' flanking region of the GA21 gave rise to an amplicon of 72 bp. These fragments are clearly distinguishable in agarose gels and have been reproduced successfully in a different laboratory. Hence, the proposed method comprises a rapid, simple, reliable, and sensitive (down to 0.05%) PCR-based assay, suitable for detection of these four GM maize lines in a single reaction.

  7. Development and Interlaboratory Validation of a Simple Screening Method for Genetically Modified Maize Using a ΔΔC(q)-Based Multiplex Real-Time PCR Assay.

    PubMed

    Noguchi, Akio; Nakamura, Kosuke; Sakata, Kozue; Sato-Fukuda, Nozomi; Ishigaki, Takumi; Mano, Junichi; Takabatake, Reona; Kitta, Kazumi; Teshima, Reiko; Kondo, Kazunari; Nishimaki-Mogami, Tomoko

    2016-04-19

    A number of genetically modified (GM) maize events have been developed and approved worldwide for commercial cultivation. A screening method is needed to monitor GM maize approved for commercialization in countries that mandate the labeling of foods containing a specified threshold level of GM crops. In Japan, a screening method has been implemented to monitor approved GM maize since 2001. However, the screening method currently used in Japan is time-consuming and requires generation of a calibration curve and experimental conversion factor (C(f)) value. We developed a simple screening method that avoids the need for a calibration curve and C(f) value. In this method, ΔC(q) values between the target sequences and the endogenous gene are calculated using multiplex real-time PCR, and the ΔΔC(q) value between the analytical and control samples is used as the criterion for determining analytical samples in which the GM organism content is below the threshold level for labeling of GM crops. An interlaboratory study indicated that the method is applicable independently with at least two models of PCR instruments used in this study.

  8. Variability of control data and relevance of observed group differences in five oral toxicity studies with genetically modified maize MON810 in rats.

    PubMed

    Schmidt, Kerstin; Schmidtke, Jörg; Schmidt, Paul; Kohl, Christian; Wilhelm, Ralf; Schiemann, Joachim; van der Voet, Hilko; Steinberg, Pablo

    2017-04-01

    The data of four 90-day feeding trials and a 1-year feeding trial with the genetically modified (GM) maize MON810 in Wistar Han RCC rats performed in the frame of EU-funded project GRACE were analysed. Firstly, the data obtained from the groups having been fed the non-GM maize diets were combined to establish a historical control data set for Wistar Han RCC rats at the animal housing facility (Slovak Medical University, Bratislava, Slovakia). The variability of all parameters is described, and the reference values and ranges have been derived. Secondly, the consistency of statistically significant differences found in the five studies was analysed. In order to do so, the body weight development, organ weight, haematology and clinical biochemistry data were compared between the studies. Based on the historical control data, equivalence ranges for these parameters were defined, and the values measured in the GM maize-fed groups were compared with these equivalence ranges. Thirdly, the (statistical) power of these feeding studies with whole food/feed was assessed and detectable toxicologically relevant group differences were derived. Linear mixed models (LMM) were applied, and standardized effect sizes (SES) were calculated in order to compare different parameters as well as to provide an overall picture of group and study differences at a glance. The comparison of the five feeding trials showed a clear study effect in the control data. It also showed inconsistency both in the frequency of statistically significant differences and in the difference values between control and test groups.

  9. Low-molecular weight protein profiling of genetically modified maize using fast liquid chromatography electrospray ionization and time-of-flight mass spectrometry.

    PubMed

    Koc, Anna; Cañuelo, Ana; Garcia-Reyes, Juan F; Molina-Diaz, Antonio; Trojanowicz, Marek

    2012-06-01

    In this work, the use of liquid chromatography coupled to electrospray time-of-flight mass spectrometry (LC-TOFMS) has been evaluated for the profiling of relatively low-molecular weight protein species in both genetically modified (GM) and non-GM maize. The proposed approach consisted of a straightforward sample fractionation with different water and ethanol-based buffer solutions followed by separation and detection of the protein species using liquid chromatography with a small particle size (1.8 μm) C(18) column and electrospray-time-of-flight mass spectrometry detection in the positive ionization mode. The fractionation of maize reference material containing different content of transgenic material (from 0 to 5% GM) led to five different fractions (albumins, globulins, zeins, zein-like glutelins, and glutelins), all of them containing different protein species (from 2 to 52 different species in each fraction). Some relevant differences in the quantity and types of protein species were observed in the different fractions of the reference material (with different GM contents) tested, thus revealing the potential use of the proposed approach for fast protein profiling and to detect tentative GMO markers in maize.

  10. Degradation of Cry1Ab protein from genetically modified maize (MON810) in relation to total dietary feed proteins in dairy cow digestion.

    PubMed

    Paul, Vijay; Guertler, Patrick; Wiedemann, Steffi; Meyer, Heinrich H D

    2010-08-01

    To investigate the relative degradation and fragmentation pattern of the recombinant Cry1Ab protein from genetically modified (GM) maize MON810 throughout the gastrointestinal tract (GIT) of dairy cows, a 25 months GM maize feeding study was conducted on 36 lactating Bavarian Fleckvieh cows allocated into two groups (18 cows per group) fed diets containing either GM maize MON810 or nearly isogenic non-GM maize as the respective diet components. All cows were fed a partial total mixed ration (pTMR). During the feeding trial, 8 feed (4 transgenic (T) and 4 non-transgenic (NT) pTMR) and 42 feces (26 T and 18 NT) samples from the subset of cows fed T and NT diets, and at the end of the feeding trial, digesta contents of rumen, abomasum, small intestine, large intestine and cecum were collected after the slaughter of six cows of each feeding group. Samples were analyzed for Cry1Ab protein and total protein using Cry1Ab specific ELISA and bicinchoninic acid assay, respectively. Immunoblot analyses were performed to evaluate the integrity of Cry1Ab protein in feed, digesta and feces samples. A decrease to 44% in Cry1Ab protein concentration from T pTMR to the voided feces (9.40 versus 4.18 mug/g of total proteins) was recorded. Concentrations of Cry1Ab protein in GIT digesta of cows fed T diets varied between the lowest 0.38 mug/g of total proteins in abomasum to the highest 3.84 mug/g of total proteins in rumen. Immunoblot analysis revealed the extensive degradation of recombinant Cry1Ab protein into a smaller fragment of around 34 kDa in GIT. The results of the present study indicate that the recombinant Cry1Ab protein from MON810 is increasingly degraded into a small fragment during dairy cow digestion.

  11. Transportable data from non-target arthropod field studies for the environmental risk assessment of genetically modified maize expressing an insecticidal double-stranded RNA.

    PubMed

    Ahmad, Aqeel; Negri, Ignacio; Oliveira, Wladecir; Brown, Christopher; Asiimwe, Peter; Sammons, Bernard; Horak, Michael; Jiang, Changjian; Carson, David

    2016-02-01

    As part of an environmental risk assessment, the potential impact of genetically modified (GM) maize MON 87411 on non-target arthropods (NTAs) was evaluated in the field. MON 87411 confers resistance to corn rootworm (CRW; Diabrotica spp.) by expressing an insecticidal double-stranded RNA (dsRNA) transcript and the Cry3Bb1 protein and tolerance to the herbicide glyphosate by producing the CP4 EPSPS protein. Field trials were conducted at 14 sites providing high geographic and environmental diversity within maize production areas from three geographic regions including the U.S., Argentina, and Brazil. MON 87411, the conventional control, and four commercial conventional reference hybrids were evaluated for NTA abundance and damage. Twenty arthropod taxa met minimum abundance criteria for valid statistical analysis. Nine of these taxa occurred in at least two of the three regions and in at least four sites across regions. These nine taxa included: aphid, predatory earwig, lacewing, ladybird beetle, leafhopper, minute pirate bug, parasitic wasp, sap beetle, and spider. In addition to wide regional distribution, these taxa encompass the ecological functions of herbivores, predators and parasitoids in maize agro-ecosystems. Thus, the nine arthropods may serve as representative taxa of maize agro-ecosystems, and thereby support that analysis of relevant data generated in one region can be transportable for the risk assessment of the same or similar GM crop products in another region. Across the 20 taxa analyzed, no statistically significant differences in abundance were detected between MON 87411 and the conventional control for 123 of the 128 individual-site comparisons (96.1%). For the nine widely distributed taxa, no statistically significant differences in abundance were detected between MON 87411 and the conventional control. Furthermore, no statistically significant differences were detected between MON 87411 and the conventional control for 53 out of 56 individual

  12. Effects of genetically modified maize events expressing Cry34Ab1, Cry35Ab1, Cry1F, and CP4 EPSPS proteins on arthropod complex food webs.

    PubMed

    Pálinkás, Zoltán; Kiss, József; Zalai, Mihály; Szénási, Ágnes; Dorner, Zita; North, Samuel; Woodward, Guy; Balog, Adalbert

    2017-04-01

    Four genetically modified (GM) maize (Zea mays L.) hybrids (coleopteran resistant, coleopteran and lepidopteran resistant, lepidopteran resistant and herbicide tolerant, coleopteran and herbicide tolerant) and its non-GM control maize stands were tested to compare the functional diversity of arthropods and to determine whether genetic modifications alter the structure of arthropods food webs. A total number of 399,239 arthropod individuals were used for analyses. The trophic groups' number and the links between them indicated that neither the higher magnitude of Bt toxins (included resistance against insect, and against both insects and glyphosate) nor the extra glyphosate treatment changed the structure of food webs. However, differences in the average trophic links/trophic groups were detected between GM and non-GM food webs for herbivore groups and plants. Also, differences in characteristic path lengths between GM and non-GM food webs for herbivores were observed. Food webs parameterized based on 2-year in-field assessments, and their properties can be considered a useful and simple tool to evaluate the effects of Bt toxins on non-target organisms.

  13. MaizeGDB: The Maize Genetics and Genomics Database.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    MaizeGDB is the community database for biological information about the crop plant Zea mays. Genomic, genetic, sequence, gene product, functional characterization, literature reference, and person/organization contact information are among the datatypes stored at MaizeGDB. At the project’s website...

  14. Genetic mechanisms of Maize dwarf mosaic virus resistance in maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize resistance to viruses has been well-characterized at the genetic level, and loci responsible for resistance to potyviruses including Maize dwarf mosaic virus (MDMV), Sugarcane mosaic virus (SCMV), Sorghum mosaic virus (SrMV), and Johnsongrass mosaic virus (JGMV), have been mapped in several ge...

  15. MaizeGDB: The Maize Genetics and Genomics Database.

    PubMed

    Harper, Lisa; Gardiner, Jack; Andorf, Carson; Lawrence, Carolyn J

    2016-01-01

    MaizeGDB is the community database for biological information about the crop plant Zea mays. Genomic, genetic, sequence, gene product, functional characterization, literature reference, and person/organization contact information are among the datatypes stored at MaizeGDB. At the project's website ( http://www.maizegdb.org ) are custom interfaces enabling researchers to browse data and to seek out specific information matching explicit search criteria. In addition, pre-compiled reports are made available for particular types of data and bulletin boards are provided to facilitate communication and coordination among members of the community of maize geneticists.

  16. Answers to critics: Why there is a long term toxicity due to a Roundup-tolerant genetically modified maize and to a Roundup herbicide.

    PubMed

    Séralini, Gilles-Eric; Mesnage, Robin; Defarge, Nicolas; Gress, Steeve; Hennequin, Didier; Clair, Emilie; Malatesta, Manuela; de Vendômois, Joël Spiroux

    2013-03-01

    Our recent work (Séralini et al., 2012) remains to date the most detailed study involving the life-long consumption of an agricultural genetically modified organism (GMO). This is true especially for NK603 maize for which only a 90-day test for commercial release was previously conducted using the same rat strain (Hammond et al., 2004). It is also the first long term detailed research on mammals exposed to a highly diluted pesticide in its total formulation with adjuvants. This may explain why 75% of our first criticisms arising within a week, among publishing authors, come from plant biologists, some developing patents on GMOs, even if it was a toxicological paper on mammals, and from Monsanto Company who owns both the NK603 GM maize and Roundup herbicide (R). Our study has limits like any one, and here we carefully answer to all criticisms from agencies, consultants and scientists, that were sent to the Editor or to ourselves. At this level, a full debate is biased if the toxicity tests on mammals of NK603 and R obtained by Monsanto Company remain confidential and thus unavailable in an electronic format for the whole scientific community to conduct independent scrutiny of the raw data. In our article, the conclusions of long-term NK603 and Roundup toxicities came from the statistically highly discriminant findings at the biochemical level in treated groups in comparison to controls, because these findings do correspond in an blinded analysis to the pathologies observed in organs, that were in turn linked to the deaths by anatomopathologists. GM NK603 and R cannot be regarded as safe to date.

  17. Impact of genetic structures on haploid genome-based quantification of genetically modified DNA: theoretical considerations, experimental data in MON 810 maize kernels (Zea mays L.) and some practical applications.

    PubMed

    Zhang, David; Corlet, Aurélie; Fouilloux, Stephane

    2008-06-01

    Real-time Polymerase Chain Reaction (PCR) based assays are widely used to estimate the content of genetically modified (GM) materials in food, feed and seed. It has been known that the genetic structures of the analyte can significantly influence the GM content expressed by the haploid genome (HG) % estimated using real-time PCR assays; this kind of influence is also understood as the impact of biological factors. The influence was first simulated at theoretical level using maize as a model. We then experimentally assessed the impact of biological factors on quantitative results, analysing by quantitative real-time PCR six maize MON 810 hybrid kernels with different genetic structures: (1) hemizygous from transgenic male parent, (2) hemizygous from transgenic female parent and (3) homozygous at the transgenic locus. The results obtained in the present study showed clear influences of biological factors on GM DNA quantification: 1% of GM materials by weight (wt) for the three genetic structures contained 0.39, 0.55 and 1.0% of GM DNA by HG respectively, from quantitative real-time PCR analyses. The relationships between GM wt% and GM HG% can be empirically established as: (1) in the case of the presence of a single GM trait: GM HG% = GM wt% x (0.5 +/- 0.167Y), where Y is the endosperm DNA content (%) in the total DNA of a maize kernel, (2) in the case of the presence of multiple GM traits: GM HG% = N x GM wt% x (0.5 +/- 0.167Y), where N is the number of GM traits (stacked or not) present in an unknown sample. This finding can be used by stakeholders related to GMO for empirical prediction from one unit of expression to another in the monitoring of seed and grain production chains. Practical equations have also been suggested for haploid copy number calculations, using hemizygous GM materials for calibration curves.

  18. Real-time quantitative PCR detection of genetically modified Maximizer maize and Roundup Ready soybean in some representative foods.

    PubMed

    Vaïtilingom, M; Pijnenburg, H; Gendre, F; Brignon, P

    1999-12-01

    A fast and quantitative method was developed to detect transgenic "Maximizer" maize "event 176" (Novartis) and "Roundup Ready" soybean (Monsanto) in food by real-time quantitative PCR. The use of the ABI Prism 7700 sequence detection system allowed the determination of the amplified product accumulation through a fluorogenic probe (TaqMan). Fluorescent dyes were chosen in such a way as to coamplify total and transgenic DNA in the same tube. Using real-time quantitative PCR, 2 pg of transgenic or total DNA per gram of starting sample was detected in 3 h after DNA extraction and the relative amounts of "Maximizer" maize and "Roundup Ready" soybean in some representative food products were quantified.

  19. Subchronic feeding study with genetically modified stacked trait lepidopteran and coleopteran resistant (DAS-Ø15Ø7-1xDAS-59122-7) maize grain in Sprague-Dawley rats.

    PubMed

    Appenzeller, Laura M; Malley, Linda; Mackenzie, Susan A; Hoban, Denise; Delaney, Bryan

    2009-07-01

    DAS-Ø15Ø7-1xDAS-59122-7 (1507x59122) is a genetically modified (GM) maize hybrid that was produced by crossing of two GM maize inbreds; DAS-Ø15Ø7-1 and DAS-59122-7. This hybrid cross expresses four transgenic proteins: Cry1F and PAT (from DAS-Ø15Ø7-1) and Cry34Ab1/Cry35Ab1 and PAT (from DAS-59122-7) that confer resistance to lepidopteran and coleopteran pests and tolerance to the herbicidal active ingredient glufosinate-ammonium. The current subchronic feeding study was conducted in Sprague-Dawley rats to evaluate the potential health effects of long-term consumption of a rodent diet containing 1507x59122 maize grain compared with a diet containing maize grain from its near-isogenic control (091). Diets formulated with three unrelated non-GM commercial hybrids (3573, 35P12, 36G12) were also included for within study reference data. All diets contained 34% (w/wt) maize grain and were prepared according to the specifications of PMI((R)) Nutrition International, LLC Certified Rodent LabDiet((R)) 5002 (PMI((R)) 5002). Diets were fed ad libitum to rats for at least 92days. OECD 408 response variables from rats fed the 1507x59122 diet were compared with those from rats fed the 091 control diet. No toxicologically significant differences were observed in nutritional performance variables, clinical and neurobehavioral signs, ophthalmology, clinical pathology (hematology, clinical chemistry, coagulation, and urinalysis), organ weights, and gross and microscopic pathology between rats in the 091 and 1507x59122 treatment groups. The results from this study demonstrate that 1507x59122 maize grain is as safe and nutritious as non-GM maize grain and support the concept that crossing of two safe GM maize events results in production of a safe stacked GM event.

  20. Development, Optimization, and Evaluation of a Duplex Droplet Digital PCR Assay To Quantify the T-nos/hmg Copy Number Ratio in Genetically Modified Maize

    PubMed Central

    2015-01-01

    Certified reference materials (CRMs) are required to guarantee the reliability of analytical measurements. The CRMs available in the field of genetically modified organisms (GMOs) are characterized using real-time polymerase chain reaction (qPCR). This technology has limited application, because of its dependence on a calibrant. The objective of this study was to obtain a method with higher metrological quality, to characterize the CRMs for their contents of T-nos/hmg copy number ratio in maize. A duplex droplet digital PCR (ddPCR) assay was developed and optimized by a central composite design. The developed method achieved an absolute limit of detection (LOD) of 11 cP T-nos, a relative LOD of 0.034%, a limit of quantification (LOQ) of 23 cP (relative LOQ of 0.08%), and a dynamic range of 0.08%–100% T-nos/hmg ratio. The specificity and applicability of the assay were established for the analysis of low T-nos concentrations (0.9%) in several corn varieties. The convenience of DNA digestion to reduce measurement bias in the case of multiple-copy binding was confirmed through an enzymatic restriction assay. Given its overall performance, this method can be used to characterize CRM candidates for their contents of T-nos/hmg ratio. PMID:26605751

  1. New analysis of a rat feeding study with a genetically modified maize reveals signs of hepatorenal toxicity.

    PubMed

    Séralini, Gilles-Eric; Cellier, Dominique; de Vendomois, Joël Spiroux

    2007-05-01

    Health risk assessment of genetically modified organisms (GMOs) cultivated for food or feed is under debate throughout the world, and very little data have been published on mid- or long-term toxicological studies with mammals. One of these studies performed under the responsibility of Monsanto Company with a transgenic corn MON863 has been subjected to questions from regulatory reviewers in Europe, where it was finally approved in 2005. This necessitated a new assessment of kidney pathological findings, and the results remained controversial. An Appeal Court action in Germany (Münster) allowed public access in June 2005 to all the crude data from this 90-day rat-feeding study. We independently re-analyzed these data. Appropriate statistics were added, such as a multivariate analysis of the growth curves, and for biochemical parameters comparisons between GMO-treated rats and the controls fed with an equivalent normal diet, and separately with six reference diets with different compositions. We observed that after the consumption of MON863, rats showed slight but dose-related significant variations in growth for both sexes, resulting in 3.3% decrease in weight for males and 3.7% increase for females. Chemistry measurements reveal signs of hepatorenal toxicity, marked also by differential sensitivities in males and females. Triglycerides increased by 24-40% in females (either at week 14, dose 11% or at week 5, dose 33%, respectively); urine phosphorus and sodium excretions diminished in males by 31-35% (week 14, dose 33%) for the most important results significantly linked to the treatment in comparison to seven diets tested. Longer experiments are essential in order to indicate the real nature and extent of the possible pathology; with the present data it cannot be concluded that GM corn MON863 is a safe product.

  2. Use of Mutant-Assisted Gene Identification and Characterization (MAGIC) to identify novel genetic loci that modify the maize hypersensitive response.

    PubMed

    Chaikam, Vijay; Negeri, Adisu; Dhawan, Rahul; Puchaka, Bala; Ji, Jiabing; Chintamanani, Satya; Gachomo, Emma W; Zillmer, Allen; Doran, Timothy; Weil, Cliff; Balint-Kurti, Peter; Johal, Guri

    2011-10-01

    The partially dominant, autoactive maize disease resistance gene Rp1-D21 causes hypersensitive response (HR) lesions to form spontaneously on leaves and stems in the absence of pathogen recognition. The maize nested association mapping (NAM) population consists of 25 200-line subpopulations each derived from a cross between the maize line B73 and one of 25 diverse inbred lines. By crossing a line carrying the Rp1-D21 gene with lines from three of these subpopulations and assessing the F(1) progeny, we were able to map several novel loci that modify the maize HR, using both single-population quantitative trait locus (QTL) and joint analysis of all three populations. Joint analysis detected QTL in greater number and with greater confidence and precision than did single population analysis. In particular, QTL were detected in bins 1.02, 4.04, 9.03, and 10.03. We have previously termed this technique, in which a mutant phenotype is used as a "reporter" for a trait of interest, Mutant-Assisted Gene Identification and Characterization (MAGIC).

  3. Genetic architecture of domestication-related traits in maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Strong directional selection occurred during the domestication of maize from its wild ancestor teosinte, reducing its genetic diversity, particularly at genes controlling domestication-related traits. Nevertheless, variability for some domestication-related traits is maintained in maize. The genet...

  4. The genetic architecture of maize height.

    PubMed

    Peiffer, Jason A; Romay, Maria C; Gore, Michael A; Flint-Garcia, Sherry A; Zhang, Zhiwu; Millard, Mark J; Gardner, Candice A C; McMullen, Michael D; Holland, James B; Bradbury, Peter J; Buckler, Edward S

    2014-04-01

    Height is one of the most heritable and easily measured traits in maize (Zea mays L.). Given a pedigree or estimates of the genomic identity-by-state among related plants, height is also accurately predictable. But, mapping alleles explaining natural variation in maize height remains a formidable challenge. To address this challenge, we measured the plant height, ear height, flowering time, and node counts of plants grown in >64,500 plots across 13 environments. These plots contained >7300 inbreds representing most publically available maize inbreds in the United States and families of the maize Nested Association Mapping (NAM) panel. Joint-linkage mapping of quantitative trait loci (QTL), fine mapping in near isogenic lines (NILs), genome-wide association studies (GWAS), and genomic best linear unbiased prediction (GBLUP) were performed. The heritability of maize height was estimated to be >90%. Mapping NAM family-nested QTL revealed the largest explained 2.1 ± 0.9% of height variation. The effects of two tropical alleles at this QTL were independently validated by fine mapping in NIL families. Several significant associations found by GWAS colocalized with established height loci, including brassinosteroid-deficient dwarf1, dwarf plant1, and semi-dwarf2. GBLUP explained >80% of height variation in the panels and outperformed bootstrap aggregation of family-nested QTL models in evaluations of prediction accuracy. These results revealed maize height was under strong genetic control and had a highly polygenic genetic architecture. They also showed that multiple models of genetic architecture differing in polygenicity and effect sizes can plausibly explain a population's variation in maize height, but they may vary in predictive efficacy.

  5. Maize Genetics and Genomics Database

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The 2007 report for MaizeGDB lists the new hires who will focus on curation/outreach and the genome sequence, respectively. Currently all sequence in the database comes from a PlantGDB pipeline and is presented with deep links to external resources such as PlantGDB, Dana Farber, GenBank, the Arizona...

  6. The 50th Annual Maize Genetics Conference

    SciTech Connect

    Cone, Karen

    2014-03-26

    The 50th Annual Maize Genetics Conference was held February 27 - March 2, 2008 at the Marriott Wardman Park Hotel in Washington, D.C. As the golden anniversary of the Conference and coinciding with the release of a draft of the maize genome sequence, this was a special meeting. To publicize this unique occasion, meeting organizers hosted a press conference, which was attended by members of the press representing science and non-science publications, and an evening reception at the Smithsonian National Museum of Natural History, where the draft sequence was announced and awards were presented to Dr. Mary Clutter and Senator Kit Bond to thank them for their outstanding contributions to maize genetics and genomics research. As usual, the Conference provided an invigorating forum for exchange of recent research results in many areas of maize genetics, e.g., cytogenetics, development, molecular genetics, transposable element biology, biochemical genetics, and genomics. Results were shared via both oral and poster presentations. Invited talks were given by four distinguished geneticists: Vicki Chandler, University of Arizona; John Doebley, University of Wisconsin; Susan Wessler, University of Georgia; and Richard Wilson, Washington University. There were 46 short talks and 241 poster presentations. The Conference was attended by over 500 participants. This included a large number of first-time participants in the meeting and an increasingly visible presence by individuals from underrepresented groups. Although we do not have concrete counts, there seem to be more African American, African and Hispanic/Latino attendees coming to the meeting than in years past. In addition, this meeting attracted many participants from outside the U.S. Student participation continues to be hallmark of the spirit of free exchange and cooperation characteristic of the maize genetics community. With the generous support provided by DOE, USDA NSF, and corporate/private donors, organizers were

  7. Universal primer-multiplex-polymerase chain reaction (UP-M-PCR) and capillary electrophoresis-laser-induced fluorescence analysis for the simultaneous detection of six genetically modified maize lines.

    PubMed

    Zhang, Chunjiao; Xu, Wentao; Zhai, Zhifang; Luo, Yunbo; Yan, Xinghua; Zhang, Nan; Huang, Kunlun

    2011-05-25

    To meet the labeling and traceability requirement of genetically modified (GM) maize and their products for trade and regulation, it is essential to develop a specific detection method for monitoring the presence of GM content. In this work, six GM maize lines, including GA21, Bt11, NK603, Bt176, Mir604, and Mon810, were simultaneously detected by universal primer-multiplex-polymerase chain reaction (UP-M-PCR), and the amplicons for the six event-specific genes as well as the endogenous Ivr gene were successfully separated by the method of capillary electrophoresis-laser-induced fluorescence (CE-LIF). The UP-M-PCR method overcame the disadvantages in conventional M-PCR, such as complex manipulation, lower sensitivity, amplification disparity resulting from different primers, etc., and in combination with CE-LIF, it obtained a high sensitivity of 0.1 ng for both single and mixed DNA samples. The established method can be widely used for the qualitative identification of the GM maize lines.

  8. Entering the second century of maize quantitative genetics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize is the most widely grown cereal in the world. In addition to its role in global agriculture, it has also long served as a model organism for genetic research. Maize stands at a genetic crossroads, as it has access to all the tools available for plant genetics but exhibits a genetic architectur...

  9. Expanding maize genetic resources with predomestication alleles: maize-teosinte introgression populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Teosinte (Zea mays ssp. parviglumis) has greater genetic diversity than maize inbreds and landraces (Z. mays ssp. mays). There are, however, limited genetic resources to efficiently evaluate and tap this diversity. To broaden resources for genetic diversity studies in maize, we developed and evaluat...

  10. A 90-day subchronic feeding study of genetically modified maize expressing Cry1Ac-M protein in Sprague-Dawley rats.

    PubMed

    Liu, Pengfei; He, Xiaoyun; Chen, Delong; Luo, Yunbo; Cao, Sishuo; Song, Huan; Liu, Ting; Huang, Kunlun; Xu, Wentao

    2012-09-01

    The cry1Ac-M gene, coding one of Bacillus thuringiensis (Bt) crystal proteins, was introduced into maize H99 × Hi IIB genome to produce insect-resistant GM maize BT-38. The food safety assessment of the BT-38 maize was conducted in Sprague-Dawley rats by a 90-days feeding study. We incorporated maize grains from BT-38 and H99 × Hi IIB into rodent diets at three concentrations (12.5%, 25%, 50%) and administered to Sprague-Dawley rats (n=10/sex/group) for 90 days. A commercialized rodent diet was fed to an additional group as control group. Body weight, feed consumption and toxicological response variables were measured, and gross as well as microscopic pathology were examined. Moreover, detection of residual Cry1Ac-M protein in the serum of rats fed with GM maize was conducted. No death or adverse effects were observed in the current feeding study. No adverse differences in the values of the response variables were observed between rats that consumed diets containing GM maize BT-38 and non-GM maize H99 × Hi IIB. No detectable Cry1Ac-M protein was found in the serum of rats after feeding diets containing GM maize for 3 months. The results demonstrated that BT-38 maize is as safe as conventional non-GM maize.

  11. Use of Mutant-Assisted Gene Identification and Characterization (MAGIC) to identify novel genetic loci that modify the maize hypersensitive response

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The partially-dominant, autoactive maize disease resistance gene Rp1-D21 causes hypersensitive response (HR) lesions to form spontaneously on the leaves and stem in the absence of pathogen recognition. The maize nested association mapping (NAM) population consists of 25 200-line subpopulations each...

  12. Plant characterization of genetically modified maize hybrids MON-89Ø34-3 × MON-88Ø17-3, MON-89Ø34-3 × MON-ØØ6Ø3-6, and MON-ØØ6Ø3-6: alternatives for maize production in Mexico.

    PubMed

    Heredia Díaz, Oscar; Aldaba Meza, José Luis; Baltazar, Baltazar M; Bojórquez Bojórquez, Germán; Castro Espinoza, Luciano; Corrales Madrid, José Luis; de la Fuente Martínez, Juan Manuel; Durán Pompa, Héctor Abel; Alonso Escobedo, José; Espinoza Banda, Armando; Garzón Tiznado, José Antonio; González García, Juvencio; Guzmán Rodríguez, José Luis; Madueño Martínez, Jesús Ignacio; Martínez Carrillo, José Luis; Meng, Chen; Quiñones Pando, Francisco Javier; Rosales Robles, Enrique; Ruiz Hernández, Ignacio; Treviño Ramírez, José Elías; Uribe Montes, Hugo Raúl; Zavala García, Francisco

    2017-02-01

    Environmental risk assessment (ERA) of genetically modified (GM) crops is a process to evaluate whether the biotechnology trait(s) in a GM crop may result in increased pest potential or harm to the environment. In this analysis, two GM insect-resistant (IR) herbicide-tolerant maize hybrids (MON-89Ø34-3 × MON-88Ø17-3 and MON-89Ø34-3 × MON-ØØ6Ø3-6) and one herbicide-tolerant GM hybrid (MON-ØØ6Ø3-6) were compared with conventional maize hybrids of similar genetic backgrounds. Two sets of studies, Experimental Phase and Pilot Phase, were conducted across five ecological regions (ecoregions) in Mexico during 2009-2013, and data were subject to meta-analysis. Results from the Experimental Phase studies, which were used for ERA, indicated that the three GM hybrids were not different from conventional maize for early stand count, days-to-silking, days-to-anthesis, root lodging, stalk lodging, or final stand count. Statistically significant differences were observed for seedling vigor, ear height, plant height, grain moisture, and grain yield, particularly in the IR hybrids; however, none of these phenotypic differences are expected to contribute to a biological or ecological change that would result in an increased pest potential or ecological risk when cultivating these GM hybrids. Overall, results from the Experimental Phase studies are consistent with those from other world regions, confirming that there are no additional risks compared to conventional maize. Results from Pilot Phase studies indicated that, compared to conventional maize hybrids, no differences were detected for the agronomic and phenotypic characteristics measured on the three GM maize hybrids, with the exception of grain moisture and grain yield in the IR hybrids. Since MON-89Ø34-3 × MON-88Ø17-3 and MON-89Ø34-3 × MON-ØØ6Ø3-6 confer resistance to target insect pests, they are an alternative for farmers in Mexico to protect the crop from insect damage. Additionally, the

  13. Genetic analysis of teosinte for kernel composition traits in maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Teosinte (Zea mays ssp. parviglumis) is the wild ancestor of modern maize (Zea mays ssp. mays). Teosinte contains greater genetic diversity compared to maize inbreds and landraces, but its use is limited by insufficient genetic resources to evaluate its value. A population of teosinte near isogenic ...

  14. The art and design of genetic screens: maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize (Zea mays) is an excellent model for basic research. Genetic screens have informed our understanding of developmental processes, meiosis, epigenetics and biochemical pathways--not only in maize but also in other cereal crops. We discuss the forward and reverse genetic screens that are possible...

  15. Entering the second century of maize quantitative genetics

    PubMed Central

    Wallace, J G; Larsson, S J; Buckler, E S

    2014-01-01

    Maize is the most widely grown cereal in the world. In addition to its role in global agriculture, it has also long served as a model organism for genetic research. Maize stands at a genetic crossroads, as it has access to all the tools available for plant genetics but exhibits a genetic architecture more similar to other outcrossing organisms than to self-pollinating crops and model plants. In this review, we summarize recent advances in maize genetics, including the development of powerful populations for genetic mapping and genome-wide association studies (GWAS), and the insights these studies yield on the mechanisms underlying complex maize traits. Most maize traits are controlled by a large number of genes, and linkage analysis of several traits implicates a ‘common gene, rare allele' model of genetic variation where some genes have many individually rare alleles contributing. Most natural alleles exhibit small effect sizes with little-to-no detectable pleiotropy or epistasis. Additionally, many of these genes are locked away in low-recombination regions that encourage the formation of multi-gene blocks that may underlie maize's strong heterotic effect. Domestication left strong marks on the maize genome, and some of the differences in trait architectures may be due to different selective pressures over time. Overall, maize's advantages as a model system make it highly desirable for studying the genetics of outcrossing species, and results from it can provide insight into other such species, including humans. PMID:23462502

  16. Genetic erosion in maize's center of origin.

    PubMed

    Dyer, George A; López-Feldman, Alejandro; Yúnez-Naude, Antonio; Taylor, J Edward

    2014-09-30

    Crop genetic diversity is an indispensable resource for farmers and professional breeders responding to changing climate, pests, and diseases. Anecdotal appraisals in centers of crop origin have suggested serious threats to this diversity for over half a century. However, a nationwide inventory recently found all maize races previously described for Mexico, including some formerly considered nearly extinct. A flurry of social studies seems to confirm that farmers maintain considerable diversity. Here, we compare estimates of maize diversity from case studies over the past 15 y with nationally and regionally representative matched longitudinal data from farmers across rural Mexico. Our findings reveal an increasing bias in inferences based on case study results and widespread loss of diversity. Cross-sectional, case study data suggest that farm-level richness has increased by 0.04 y(-1) nationwide; however, direct estimates using matched longitudinal data reveal that richness dropped -0.04 y(-1) between 2002 and 2007, from 1.43 to 1.22 varieties per farm. Varietal losses occurred across regions and altitudinal zones, and regardless of farm turnover within the sector. Extinction of local maize populations may not have resulted in an immediate loss of alleles, but low varietal richness and changes in maize's metapopulation dynamics may prevent farmers from accessing germplasm suitable to a rapidly changing climate. Declining yields could then lead farmers to leave the sector and result in a further loss of diversity. Similarities in research approaches across crops suggest that methodological biases could conceal a loss of diversity at other centers of crop origin.

  17. Random amplified polymorphic DNA analysis of genetically modified organisms.

    PubMed

    Yoke-Kqueen, Cheah; Radu, Son

    2006-12-15

    Randomly amplified polymorphic DNA (RAPD) was used to analyzed 78 samples comprises of certified reference materials (soya and maize powder), raw seeds (soybean and maize), processed food and animal feed. Combination assay of two arbitrary primers in the RAPD analysis enable to distinguish genetically modified organism (GMO) reference materials from the samples tested. Dendrogram analysis revealed 13 clusters at 45% similarity from the RAPD. RAPD analysis showed that the maize and soybean samples were clustered differently besides the GMO and non-GMO products.

  18. Genetically modified bacteriophages.

    PubMed

    Sagona, Antonia P; Grigonyte, Aurelija M; MacDonald, Paul R; Jaramillo, Alfonso

    2016-04-18

    Phages or bacteriophages, viruses that infect and replicate inside bacteria, are the most abundant microorganisms on earth. The realization that antibiotic resistance poses a substantial risk to the world's health and global economy is revitalizing phage therapy as a potential solution. The increasing ease by which phage genomes can be modified, owing to the influx of new technologies, has led to an expansion of their natural capabilities, and a reduced dependence on phage isolation from environmental sources. This review will discuss the way synthetic biology has accelerated the construction of genetically modified phages and will describe the wide range of their applications. It will further provide insight into the societal and economic benefits that derive from the use of recombinant phages in various sectors, from health to biodetection, biocontrol and the food industry.

  19. Genetic control of leaf curl in maize.

    PubMed

    Entringer, G C; Guedes, F L; Oliveira, A A; Nascimento, J P; Souza, J C

    2014-03-17

    Among the many implications of climatic change on agriculture, drought is expected to continue to have a major impact on agribusinesses. Leaf curling is an anatomical characteristic that might be potentially used to enhance plant tolerance to water deficit. Hence, we aimed to study the genetic control of leaf curl in maize. From 2 contrasting inbred lines for the trait, generations F1, F2, and the backcrosses were obtained. All of these generations were evaluated in a randomized block design with 2 replicates. Leaf curl samples were collected from 3 leaves above the first ear at the tasseling stage, and quantified by dividing the width of the leaf blade with natural curling against its extended width. The mean and variance components were estimated by the weighted least square method. It was found that the trait studied has predominance of the additive effects, with genetic control being attributed to few genes that favor selection and exhibit minimal influence from the environment.

  20. Effects of an active immunization on the immune response of laying Japanese quail (Coturnix coturnix japonica) fed with or without genetically modified Bacillus thuringiensis-maize.

    PubMed

    Scholtz, N D; Halle, I; Dänicke, S; Hartmann, G; Zur, B; Sauerwein, H

    2010-06-01

    Potentially adverse effects of diets containing transgenic plants are a concern for many consumers, particularly in Europe. For Bacillus thuringiensis-maize, several studies in livestock and poultry showed that the zootechnical data provide no indication for such adverse effects. These studies were all done in homeostatic situations; it remained open whether a deflection of the regulatory physiological systems might yield divergent dynamic responses in B. thuringiensis-maize-fed animals. We therefore tested the effect of an active immunization using BSA as antigen in a feeding regimen with or without B. thuringiensis-maize using quail as a model organism. Newly hatched Japanese quail were randomly allocated to 2 groups (n=120 per group) fed with diets containing either B. thuringiensis-maize or isogenic maize of the same cultivar. The diets did not differ in concentrations of the mycotoxins deoxynivalenol and zearalenone, which were both far below guidance values. After 16 wk on the experimental diets, one-half of each group was immunized against BSA. The remaining birds were injected with saline. Thirty-six hours after the injection, half of the BSA-injected subgroup (n=30) and half of the saline subgroup (n=30) from B. thuringiensis-maize- and isogenic-fed birds were killed and blood samples were collected and analyzed for serum zinc levels, indicative for acute phase response. For determining IgY-mediated immune responses, eggs were collected every other week for 6 wk after the injections from the remaining birds and total IgY concentrations and BSA-specific IgY titers were measured in egg yolk. The BSA injections did not elicit significant decreases of serum zinc concentrations. The serum zinc levels were significantly higher in B. thuringiensis-maize-fed quail. Expectedly, total IgY as well as BSA-specific IgY titers increased with time in the BSA-immunized quail. The response of both variables to the BSA injection did not differ between the feeding groups

  1. Breeding Specialty Starch Maize Using Exotic Genetic Resources for Gene Discovery of Novel Alleles and Modifiers with Materials Generated from the USDA-ARS GEM Project

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Amylomaize VII, a class of High Amylose Maize with at least 70% of the kernel starch composed of the linear amylose polymer, has had numerous food and industrial applications including the manufacturing of biodegradable plastics, adhesives and candies. More recently it has been found to be a signi...

  2. Development of multiplex PCR method for simultaneous detection of four events of genetically modified maize: DAS-59122-7, MIR604, MON863 and MON88017.

    PubMed

    Oguchi, Taichi; Onishi, Mari; Mano, Junichi; Akiyama, Hiroshi; Teshima, Reiko; Futo, Satoshi; Furui, Satoshi; Kitta, Kazumi

    2010-01-01

    A novel multiplex PCR method was developed for simultaneous event-specific detection of four events of GM maize, i.e., DAS-59122-7, MIR604, MON88017, and MON863. The single laboratory examination of analytical performance using simulated DNA mixtures containing GM DNA at various concentrations in non-GM DNA suggested that the limits of detection (LOD) of the multiplex PCR method were 0.16% for MON863, MIR604, and MON88017, and 0.078% for DAS-59122-7. We previously developed a nonaplex (9plex) PCR method for eight events of GM maize, i.e., Bt11, Bt176, GA21, MON810, MON863, NK603, T25, and TC1507. Together with the nonaplex PCR method, the newly developed method enabled the detection and identification of eleven GM maize events that are frequently included in commercial GM seed used in Japan. In addition, this combinational analysis may be useful for the identification of combined event products of GM maize.

  3. Molecular genetic approaches to developing quality protein maize.

    PubMed

    Gibbon, Bryan C; Larkins, Brian A

    2005-04-01

    Since its development more than two decades ago, Quality Protein Maize (QPM) has been adopted for cultivation in many regions of the developing world. Given the potential benefits of widespread use of QPM, research to better understand the genetic and biochemical mechanisms responsible for its altered kernel texture and protein quality is important. Recent investigations into the improved protein quality of the opaque2 mutant and the genetic mechanisms that can suppress its starchy kernel phenotype provide new insights to support the continued improvement of QPM. Chief among these developments are the use of transgenic approaches to improve nutritional quality and the discovery that an important component of modified endosperm texture in QPM is related to altered starch granule structure.

  4. Genetic Properties of the Maize Nested Association Mapping Population

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize is one of the world’s most diverse species, and this variation can be used to understand the molecular basis of phenotypic variation and to improve agricultural efficiency and sustainability. To access this genetic variation, 25 diverse inbred maize lines were crossed to the B73 reference lin...

  5. Genetic diversity and selection in the maize starch pathway

    PubMed Central

    Whitt, Sherry R.; Wilson, Larissa M.; Tenaillon, Maud I.; Gaut, Brandon S.; Buckler, Edward S.

    2002-01-01

    Maize is both phenotypically and genetically diverse. Sequence studies generally confirm the extensive genetic variability in modern maize is consistent with a lack of selection. For more than 6,000 years, Native Americans and modern breeders have exploited the tremendous genetic diversity of maize (Zea mays ssp. mays) to create the highest yielding grain crop in the world. Nonetheless, some loci have relatively low levels of genetic variation, particularly loci that have been the target of artificial selection, like c1 and tb1. However, there is limited information on how selection may affect an agronomically important pathway for any crop. These pathways may retain the signature of artificial selection and may lack genetic variation in contrast to the rest of the genome. To evaluate the impact of selection across an agronomically important pathway, we surveyed nucleotide diversity at six major genes involved in starch metabolism and found unusually low genetic diversity and strong evidence of selection. Low diversity in these critical genes suggests that a paradigm shift may be required for future maize breeding. Rather than relying solely on the diversity within maize or on transgenics, future maize breeding would perhaps benefit from the incorporation of alleles from maize's wild relatives. PMID:12244216

  6. Why genetically modified crops?

    PubMed

    Jones, Jonathan D G

    2011-05-13

    This paper is intended to convey the message of the talk I gave at the Theo Murphy meeting at the Kavli Centre in July 2010. It, like the talk, is polemical, and conveys the exasperation felt by a practitioner of genetically modified (GM) plant science at its widespread misrepresentation. I argue that sustainable intensification of agriculture, using GM as well as other technologies, reduces its environmental impact by reducing pesticide applications and conserving soil carbon by enabling low till methods. Current technologies (primarily insect resistance and herbicide tolerance) have been beneficial. Moreover, the near-term pipeline of new GM methods and traits to enhance our diet, increase crop yields and reduce losses to disease is substantial. It would be perverse to spurn this approach at a time when we need every tool in the toolbox to ensure adequate food production in the short, medium and long term.

  7. Event-specific detection of stacked genetically modified maize Bt11 x GA21 by UP-M-PCR and real-time PCR.

    PubMed

    Xu, Wentao; Yuan, Yanfang; Luo, Yunbo; Bai, Weibin; Zhang, Chunjiao; Huang, Kunlun

    2009-01-28

    More and more stacked GMOs have been developed for more improved functional properties and/or a stronger intended characteristic, such as antipest, improved product efficiency etc. Bt11 x GA21 is a new kind of stacked GM maize developed by Monsanto Company. Since there are no unique flanking sequences in stacked GMOs, up to now, no appropriate method has been reported to accurately detect them. In this passage, a novel universal primer multiplex PCR (UP-M-PCR) was developed and applied as a rapid screening method for the simultaneous detection of five target sequences (NOS, 35S, Bt11 event, GA21 event, and IVR) in maize Bt11 x GA21. This method overcame the disadvantages rooted deeply in conventional multiplex PCR such as complex manipulation, lower sensitivity, self-inhibition and amplification disparity resulting from different primers. What's more, it got a high specificity and had a detection limit of 0.1% (approximates to 38 haploid genome copies). Furthermore, real-time PCR combined with multivariate statistical analysis was used for accurate quantification of stacked GM maize Bt11 x GA21 in 100% GM maize mixture (Bt11 x GA21, Bt11 and GA21). Detection results showed that this method could accurately validate the content of Bt11, GA21 and Bt11 x GA21 in 100% GM mixture with a detection limit of 0.5% (approximates to 200 haploid genome copies) and a low relative standard deviation <5%. All the data proved that this method may be widely applied in event-specific detection of other stacked GMOs in GM-mixture.

  8. Fate of Cry1Ab protein in agricultural systems under slurry management of cows fed genetically modified maize (Zea mays L.) MON810: a quantitative assessment.

    PubMed

    Gruber, Helga; Paul, Vijay; Guertler, Patrick; Spiekers, Hubert; Tichopad, Ales; Meyer, Heinrich H D; Muller, Martin

    2011-07-13

    The objective of the study was to track the fate of recombinant Cry1Ab protein in a liquid manure field trial when feeding GM maize MON810 to dairy cows. A validated ELISA was applied for quantification of Cry1Ab in the agricultural chain from GM maize plants, feed, liquid manure and soil to crops grown on manured fields. Starting with 23.7 μg of Cry1Ab g(-1) dry weight GM maize material, a rapid decline of Cry1Ab levels was observed as 2.6% and 0.9% of Cry1Ab from the GM plant were detected in feed and liquid manure, respectively. Half of this residual Cry1Ab persisted during slurry storage for 25 weeks. After application to experimental fields, final degradation of Cry1Ab to below detectable levels in soil was reported. Cry1Ab exhibited a higher rate of degradation compared to total protein in the agricultural processes. Immunoblotting revealed a degradation of the 65 kDa Cry1Ab into immunoreactive fragments of lower size in all analyzed materials.

  9. The Genetic Architecture of Maize Flowering Time

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flowering time is the key trait controlling adaptation of plants to their local environment, and, in an outcrossing species like maize, it is a complex trait. Variation for this complex trait was dissected in maize using a novel set of 5000 recombinant inbred lines (maize Nested Association Mapping...

  10. Ultrasensitive detection of genetically modified maize DNA by capillary gel electrophoresis with laser-induced fluorescence using different fluorescent intercalating dyes.

    PubMed

    García-Cañas, Virginia; González, Ramón; Cifuentes, Alejandro

    2002-07-31

    In this work, four different fluorescent intercalating dyes are compared for the ultrasensitive CGE-LIF detection of DNA from transgenic maize in flours. The fluorescent intercalating dyes compared are YOPRO-1, SYBR-Green-I, Ethidium bromide (EthBr), and EnhanCE. For all the four dyes optimum concentrations are established, and efficient separations of DNA fragments ranging in size from 80 to 1000 bp are obtained. The comparative study demonstrates that SYBR-Green-I and YOPRO-1 provide better limits of detection (LODs) than EnhanCE or EthBr (i.e., LODs are, respectively, 700, 1000, 11300, and 97400 zmol, calculated for a 200-bp DNA fragment). Separations using YOPRO-1 are faster than those using SYBR-Green-I (30 min vs 47 min for the analysis of the 80-1000 bp DNA fragments). Also, separations using YOPRO-1 are more efficient than those using SYBR-Green-I (e.g., 2.4 x 10(6) plates/m vs 1.6 x 10(6) plates/m, respectively, calculated for the 200-bp fragment). Also, buffer depletion and cost per analysis are worse with SYBR-Green-I than with YOPRO-1. Therefore, YOPRO-1 was selected as the preferred intercalating dye. Using this fluorescent compound, analysis time reproducibility for the CGE-LIF separation of the DNA fragments is determined to be better than 1.7% (% RSD, n = 10) within the same day, and better than 1.9% (% RSD, n = 30) for three different days. Moreover, the fluorescence signal obtained using this dye is shown to vary linearly with the DNA concentration in the range studied, i.e., 1-500 ng/microL. It is demonstrated that by using this method 0.01% of transgenic maize can be detected in flour by direct injection of the PCR-amplified sample.

  11. The genetic architecture of maize height

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Height is one of the most heritable and easily measured traits in maize (Zea mays L.). Given a pedigree or estimates of the genomic identity-by-state (IBS) among related plants, height is also accurately predictable. But, mapping alleles explaining natural variation in maize height remains a formida...

  12. [Detection of genetic modification in maize and maize products by ELISA-test].

    PubMed

    Urbanek-Karłowska, Bogumiła; Sawilska-Rautenstrauch, Dorota; Jedra, Małgorzata; Badowski, Paweł

    2003-01-01

    Enzyme immunoassay methods--TRAIT Test--was applied for detection of genetic modification in maize seeds and foodstuffs, which have been produced from this crop. TRAIT Test is based on the identification GMO protein Cry 1Ab produced by a gene derived from Bacillus thuringiensis (Bt) incorporated into insect resistant corn grain. The experiment was carried out on maize standards and foodstuffs from Warsaw market. The positive result was obtained for one maize product, which was not labelled as GMO. The presence of GMO material was approximately equal to 1%. In conclusion, this test is proper for fast routine qualitative (yes/no) determination GMO material in maize seeds and unprocessed food products.

  13. Prospects for reducing fumonisin contamination of maize through genetic modification.

    PubMed Central

    Duvick, J

    2001-01-01

    Fumonisins (FB) are mycotoxins found in (italic)Fusarium verticillioides-infected maize grain worldwide. Attention has focused on FBs because of their widespread occurrence, acute toxicity to certain livestock, and their potential carcinogenicity. FBs are present at low levels in most field-grown maize but may spike to high levels depending on both the environment and genetics of the host plant. Among the strategies for reducing risk of FB contamination in maize supplied to the market, development and deployment of Fusarium ear mold-resistant maize germplasm is a high priority. Breeding for increased ear mold tolerance and reduced mycotoxin levels is being practiced today in both commercial and public programs, but the amount of resistance achievable may be limited due to complicated genetics and/or linkage to undesirable agronomic traits. Molecular markers can be employed to speed up the incorporation of chromosomal regions that have a quantitative effect on resistance (quantitative trait loci). Transgenic approaches to ear mold/mycotoxin resistance are now feasible as well. These potentially include genetically enhanced resistance to insect feeding, increased fungal resistance, and detoxification/prevention of mycotoxins in the grain. An example of the first of these approaches is already on the market, namely transgenic maize expressing Bacillus thuringiensis (Bt) toxin, targeted to the European corn borer. Some Bt maize hybrids have the potential to reduce FB levels in field-harvested grain, presumably through reduced feeding of Bt-susceptible insects in ear tissues. However, improved ear mold resistance per se is still an important goal, as the plant will still be vulnerable to noninsect routes of entry to (italic)Fusarium. A second approach, transgene-mediated control of the ability of Fusarium to infect and colonize the ear, could potentially be achieved through overexpression of specific antifungal proteins and metabolites, or enhancement of the plant's own

  14. The genetic architecture of maize stalk strength

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stalk strength is an important trait in maize (Zea mays L.). Strong stalks reduce lodging and maximize harvestable yield. Studies show rind penetrometer resistance (RPR), or the force required to pierce a stalk rind with a spike, is a valid approximation of strength. We measured RPR across 4,892 rec...

  15. Maize Genetic Resources Collections – Utilizing a Treasure Trove

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The maize genetic resource collection managed by the USDA-ARS's National Plant Germplasm System is heavily utilized by researchers and educators. A collection of landraces, inbred lines from public and private sector sources, synthetics and key populations, it serves both as a living snapshot of th...

  16. The Genetic Basis of Disease Resistance in Maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The advent of high throughput genomics has accelerated progress in understanding the genetic basis of disease resistance in maize, much as it enhanced discovery in other fields. Here we summarize progress made in recent years using resources such as association mapping and nested association mapping...

  17. Metabolomics of genetically modified crops.

    PubMed

    Simó, Carolina; Ibáñez, Clara; Valdés, Alberto; Cifuentes, Alejandro; García-Cañas, Virginia

    2014-10-20

    Metabolomic-based approaches are increasingly applied to analyse genetically modified organisms (GMOs) making it possible to obtain broader and deeper information on the composition of GMOs compared to that obtained from traditional analytical approaches. The combination in metabolomics of advanced analytical methods and bioinformatics tools provides wide chemical compositional data that contributes to corroborate (or not) the substantial equivalence and occurrence of unintended changes resulting from genetic transformation. This review provides insight into recent progress in metabolomics studies on transgenic crops focusing mainly in papers published in the last decade.

  18. Metabolomics of Genetically Modified Crops

    PubMed Central

    Simó, Carolina; Ibáñez, Clara; Valdés, Alberto; Cifuentes, Alejandro; García-Cañas, Virginia

    2014-01-01

    Metabolomic-based approaches are increasingly applied to analyse genetically modified organisms (GMOs) making it possible to obtain broader and deeper information on the composition of GMOs compared to that obtained from traditional analytical approaches. The combination in metabolomics of advanced analytical methods and bioinformatics tools provides wide chemical compositional data that contributes to corroborate (or not) the substantial equivalence and occurrence of unintended changes resulting from genetic transformation. This review provides insight into recent progress in metabolomics studies on transgenic crops focusing mainly in papers published in the last decade. PMID:25334064

  19. Genetic Modifiers of Ovarian Cancer

    DTIC Science & Technology

    2012-06-01

    association study ( GWAS ) for ovarian cancer in BRCA1 mutation carriers was initiated in an effort to identify common genetic variants that modify... GWAS of 1250 BRCA1 mutation carriers diagnosed with breast cancer and 1250 unaffected BRCA1 carriers using Human660W-Quad arrays. The 1250 unaffected...cancer on H uman660W-Quad arrays. In addition we acquired GWAS genotype data for 120 additional BRCA1 mutation carriers affected with ovarian

  20. Genetic Modifiers of Ovarian Cancer

    DTIC Science & Technology

    2013-06-01

    cancer suggesting the presence of genetic modifiers of ovarian cancer in this population. A genome wide association study ( GWAS ) for ovarian cancer...cancer and 1,000 age-matched unaffected BRCA1 carriers. As outlined in detail in our previous annual report, we recently conducted a GWAS of BRCA1...between ovarian cancer risk and SNPs implicated in Aim 1 by genotyping 1,500 BRCA1 ovarian cancer cases and 1,500 unaffected BRCA1 carriers. GWAS

  1. Genetic modifiers of Huntington's disease.

    PubMed

    Gusella, James F; MacDonald, Marcy E; Lee, Jong-Min

    2014-09-15

    Huntington's disease (HD) is a devastating neurodegenerative disorder that directly affects more than 1 in 10,000 persons in Western societies but, as a family disorder with a long, costly, debilitating course, it has an indirect impact on a far greater proportion of the population. Although some palliative treatments are used, no effective treatment exists for preventing clinical onset of the disorder or for delaying its inevitable progression toward premature death, approximately 15 years after diagnosis. Huntington's disease involves a movement disorder characterized by chorea, as well as a variety of psychiatric disturbances and intellectual decline, with a gradual loss of independence. A dire need exists for effective HD therapies to alleviate the suffering and costs to the individual, family, and health care system. In past decades, genetics, the study of DNA sequence variation and its consequences, provided the tools to map the HD gene to chromosome 4 and ultimately to identify its mutation as an expanded CAG trinucleotide repeat in the coding sequence of a large protein, dubbed huntingtin. Now, advances in genetic technology offer an unbiased route to the identification of genetic factors that are disease-modifying agents in human patients. Such genetic modifiers are expected to highlight processes capable of altering the course of HD and therefore to provide new, human-validated targets for traditional drug development, with the goal of developing rational treatments to delay or prevent onset of HD clinical signs.

  2. DNA extraction methods for detecting genetically modified foods: A comparative study.

    PubMed

    Elsanhoty, Rafaat M; Ramadan, Mohamed Fawzy; Jany, Klaus Dieter

    2011-06-15

    The work presented in this manuscript was achieved to compare six different methods for extracting DNA from raw maize and its derived products. The methods that gave higher yield and quality of DNA were chosen to detect the genetic modification in the samples collected from the Egyptian market. The different methods used were evaluated for extracting DNA from maize kernels (without treatment), maize flour (mechanical treatment), canned maize (sweet corn), frozen maize (sweet corn), maize starch, extruded maize, popcorn, corn flacks, maize snacks, and bread made from corn flour (mechanical and thermal treatments). The quality and quantity of the DNA extracted from the standards, containing known percentages of GMO material and from the different food products were evaluated. For qualitative detection of the GMO varieties in foods, the GMOScreen 35S/NOS test kit was used, to screen the genetic modification in the samples. The positive samples for the 35S promoter and/or the NOS terminator were identified by the standard methods adopted by EU. All of the used methods extracted yielded good DNA quality. However, we noted that the purest DNA extract were obtained using the DNA extraction kit (Roche) and this generally was the best method for extracting DNA from most of the maize-derived foods. We have noted that the yield of DNA extracted from maize-derived foods was generally lower in the processed products. The results indicated that 17 samples were positive for the presence of 35S promoter, while 34% from the samples were positive for the genetically modified maize line Bt-176.

  3. Genetic properties of the maize nested association mapping population.

    PubMed

    McMullen, Michael D; Kresovich, Stephen; Villeda, Hector Sanchez; Bradbury, Peter; Li, Huihui; Sun, Qi; Flint-Garcia, Sherry; Thornsberry, Jeffry; Acharya, Charlotte; Bottoms, Christopher; Brown, Patrick; Browne, Chris; Eller, Magen; Guill, Kate; Harjes, Carlos; Kroon, Dallas; Lepak, Nick; Mitchell, Sharon E; Peterson, Brooke; Pressoir, Gael; Romero, Susan; Oropeza Rosas, Marco; Salvo, Stella; Yates, Heather; Hanson, Mark; Jones, Elizabeth; Smith, Stephen; Glaubitz, Jeffrey C; Goodman, Major; Ware, Doreen; Holland, James B; Buckler, Edward S

    2009-08-07

    Maize genetic diversity has been used to understand the molecular basis of phenotypic variation and to improve agricultural efficiency and sustainability. We crossed 25 diverse inbred maize lines to the B73 reference line, capturing a total of 136,000 recombination events. Variation for recombination frequencies was observed among families, influenced by local (cis) genetic variation. We identified evidence for numerous minor single-locus effects but little two-locus linkage disequilibrium or segregation distortion, which indicated a limited role for genes with large effects and epistatic interactions on fitness. We observed excess residual heterozygosity in pericentromeric regions, which suggested that selection in inbred lines has been less efficient in these regions because of reduced recombination frequency. This implies that pericentromeric regions may contribute disproportionally to heterosis.

  4. Genetic Factors Involved in Fumonisin Accumulation in Maize Kernels and Their Implications in Maize Agronomic Management and Breeding

    PubMed Central

    Santiago, Rogelio; Cao, Ana; Butrón, Ana

    2015-01-01

    Contamination of maize with fumonisins depends on the environmental conditions; the maize resistance to contamination and the interaction between both factors. Although the effect of environmental factors is a determinant for establishing the risk of kernel contamination in a region, there is sufficient genetic variability among maize to develop resistance to fumonisin contamination and to breed varieties with contamination at safe levels. In addition, ascertaining which environmental factors are the most important in a region will allow the implementation of risk monitoring programs and suitable cultural practices to reduce the impact of such environmental variables. The current paper reviews all works done to address the influence of environmental variables on fumonisin accumulation, the genetics of maize resistance to fumonisin accumulation, and the search for the biochemical and/or structural mechanisms of the maize plant that could be involved in resistance to fumonisin contamination. We also explore the outcomes of breeding programs and risk monitoring of undertaken projects. PMID:26308050

  5. Genetic Factors Involved in Fumonisin Accumulation in Maize Kernels and Their Implications in Maize Agronomic Management and Breeding.

    PubMed

    Santiago, Rogelio; Cao, Ana; Butrón, Ana

    2015-08-20

    Contamination of maize with fumonisins depends on the environmental conditions; the maize resistance to contamination and the interaction between both factors. Although the effect of environmental factors is a determinant for establishing the risk of kernel contamination in a region, there is sufficient genetic variability among maize to develop resistance to fumonisin contamination and to breed varieties with contamination at safe levels. In addition, ascertaining which environmental factors are the most important in a region will allow the implementation of risk monitoring programs and suitable cultural practices to reduce the impact of such environmental variables. The current paper reviews all works done to address the influence of environmental variables on fumonisin accumulation, the genetics of maize resistance to fumonisin accumulation, and the search for the biochemical and/or structural mechanisms of the maize plant that could be involved in resistance to fumonisin contamination. We also explore the outcomes of breeding programs and risk monitoring of undertaken projects.

  6. Genetic analysis of arsenic accumulation in maize using QTL mapping

    NASA Astrophysics Data System (ADS)

    Fu, Zhongjun; Li, Weihua; Xing, Xiaolong; Xu, Mengmeng; Liu, Xiaoyang; Li, Haochuan; Xue, Yadong; Liu, Zonghua; Tang, Jihua

    2016-02-01

    Arsenic (As) is a toxic heavy metal that can accumulate in crops and poses a threat to human health. The genetic mechanism of As accumulation is unclear. Herein, we used quantitative trait locus (QTL) mapping to unravel the genetic basis of As accumulation in a maize recombinant inbred line population derived from the Chinese crossbred variety Yuyu22. The kernels had the lowest As content among the different maize tissues, followed by the axes, stems, bracts and leaves. Fourteen QTLs were identified at each location. Some of these QTLs were identified in different environments and were also detected by joint analysis. Compared with the B73 RefGen v2 reference genome, the distributions and effects of some QTLs were closely linked to those of QTLs detected in a previous study; the QTLs were likely in strong linkage disequilibrium. Our findings could be used to help maintain maize production to satisfy the demand for edible corn and to decrease the As content in As-contaminated soil through the selection and breeding of As pollution-safe cultivars.

  7. Genetic analysis of arsenic accumulation in maize using QTL mapping

    PubMed Central

    Fu, Zhongjun; Li, Weihua; Xing, Xiaolong; Xu, Mengmeng; Liu, Xiaoyang; Li, Haochuan; Xue, Yadong; Liu, Zonghua; Tang, Jihua

    2016-01-01

    Arsenic (As) is a toxic heavy metal that can accumulate in crops and poses a threat to human health. The genetic mechanism of As accumulation is unclear. Herein, we used quantitative trait locus (QTL) mapping to unravel the genetic basis of As accumulation in a maize recombinant inbred line population derived from the Chinese crossbred variety Yuyu22. The kernels had the lowest As content among the different maize tissues, followed by the axes, stems, bracts and leaves. Fourteen QTLs were identified at each location. Some of these QTLs were identified in different environments and were also detected by joint analysis. Compared with the B73 RefGen v2 reference genome, the distributions and effects of some QTLs were closely linked to those of QTLs detected in a previous study; the QTLs were likely in strong linkage disequilibrium. Our findings could be used to help maintain maize production to satisfy the demand for edible corn and to decrease the As content in As-contaminated soil through the selection and breeding of As pollution-safe cultivars. PMID:26880701

  8. Genetic analysis of arsenic accumulation in maize using QTL mapping.

    PubMed

    Fu, Zhongjun; Li, Weihua; Xing, Xiaolong; Xu, Mengmeng; Liu, Xiaoyang; Li, Haochuan; Xue, Yadong; Liu, Zonghua; Tang, Jihua

    2016-02-16

    Arsenic (As) is a toxic heavy metal that can accumulate in crops and poses a threat to human health. The genetic mechanism of As accumulation is unclear. Herein, we used quantitative trait locus (QTL) mapping to unravel the genetic basis of As accumulation in a maize recombinant inbred line population derived from the Chinese crossbred variety Yuyu22. The kernels had the lowest As content among the different maize tissues, followed by the axes, stems, bracts and leaves. Fourteen QTLs were identified at each location. Some of these QTLs were identified in different environments and were also detected by joint analysis. Compared with the B73 RefGen v2 reference genome, the distributions and effects of some QTLs were closely linked to those of QTLs detected in a previous study; the QTLs were likely in strong linkage disequilibrium. Our findings could be used to help maintain maize production to satisfy the demand for edible corn and to decrease the As content in As-contaminated soil through the selection and breeding of As pollution-safe cultivars.

  9. The population genetics of maize dwarf mosaic virus in Spain.

    PubMed

    Achon, M A; Larrañaga, A; Alonso-Dueñas, N

    2012-12-01

    The population genetics of maize dwarf mosaic virus (MDMV) in Spain was assessed by analysis of the P1-HC region. Restriction fragment length polymorphism analysis of 363 isolates revealed that the MDMV population consisted of 69 haplotypes. Sequence analysis of 112 isolates confirmed a high degree of nucleotide sequence diversity (0.143), which was higher for P1 than for the HC. Twelve sequences showed a single different recombination event. Selection pressure analysis revealed that the P1-HC region was under strong negative selection. The MDMV population was spatially structured but not structured temporally or by host. Phylogenetic analysis split the sequences into five major groups.

  10. [Therapeutic approaches using genetically modified cells].

    PubMed

    Anliker, Brigitte; Renner, Matthias; Schweizer, Matthias

    2015-11-01

    Medicinal products containing genetically modified cells are, in most cases, classified as gene therapy and cell therapy medicinal products. Although no medicinal product containing genetically modified cells has been licensed in Europe yet, a variety of therapeutic strategies using genetically modified cells are in different stages of clinical development for the treatment of acquired and inherited diseases. In this chapter, several examples of promising approaches are presented, with an emphasis on gene therapy for inherited immunodeficiencies and on tumour immunotherapy with genetically modified T-cells expressing a chimeric antigen receptor or a recombinant T-cell receptor.

  11. Genetic signals of origin, spread, and introgression in a large sample of maize landraces

    PubMed Central

    van Heerwaarden, Joost; Doebley, John; Briggs, William H.; Glaubitz, Jeffrey C.; Goodman, Major M.; de Jesus Sanchez Gonzalez, Jose; Ross-Ibarra, Jeffrey

    2011-01-01

    The last two decades have seen important advances in our knowledge of maize domestication, thanks in part to the contributions of genetic data. Genetic studies have provided firm evidence that maize was domesticated from Balsas teosinte (Zea mays subspecies parviglumis), a wild relative that is endemic to the mid- to lowland regions of southwestern Mexico. An interesting paradox remains, however: Maize cultivars that are most closely related to Balsas teosinte are found mainly in the Mexican highlands where subspecies parviglumis does not grow. Genetic data thus point to primary diffusion of domesticated maize from the highlands rather than from the region of initial domestication. Recent archeological evidence for early lowland cultivation has been consistent with the genetics of domestication, leaving the issue of the ancestral position of highland maize unresolved. We used a new SNP dataset scored in a large number of accessions of both teosinte and maize to take a second look at the geography of the earliest cultivated maize. We found that gene flow between maize and its wild relatives meaningfully impacts our inference of geographic origins. By analyzing differentiation from inferred ancestral gene frequencies, we obtained results that are fully consistent with current ecological, archeological, and genetic data concerning the geography of early maize cultivation. PMID:21189301

  12. Genetic mapping of the Isaac-CACTA transposon in maize.

    PubMed

    Lee, Ju-Kyong; Park, Jong-Yeol; Kim, Jin-Hong; Kwon, Soon-Jae; Shin, Ji-Hyeon; Hong, Soon-Kwan; Min, Hwang-Kee; Kim, Nam-Soo

    2006-06-01

    We constructed a genetic linkage map with Isaac-TD, SSR, and SNAP markers in a RIL population which had been derived from a cross of waxy corn (KW7) and dent corn (Mo17). A total of 368 markers, including 241 Isaac-TD, 121 SSR, and 6 SNAP markers, were assigned to 10 linkage groups, encompassing 1687.0 cM, with an average genetic distance of 4.6 cM between markers. SSR markers were utilized as chromosome anchors, in order to assign the Isaac-TD markers to the chromosomes, and the number of markers in each of the linkage groups ranged between 22 and 49. The majority of the Isaac-TD markers were determined to have been distributed throughout the ten maize chromosomes. In linkage analysis of the Isaac-TD markers with genes of agronomic interest, six genes related with maize kernel starch biosynthesis, ae1, bt2, sh1, sh2, su1, and wx1, were analyzed and shown that they were closely linked with either the Isaac-TD or SSR markers on chromosomes of 3, 4, 5, and 9. We observed and mapped segregation-distorted markers on chromosomes 1, 5, 6, 7, 8, and 10, where these markers were clustered. The Isaac-TD or SSR markers which were closely linked with starch synthesis genes may prove useful in marker-assisted breeding programs.

  13. Analysis of genetically modified organisms by pyrosequencing on a portable photodiode-based bioluminescence sequencer.

    PubMed

    Song, Qinxin; Wei, Guijiang; Zhou, Guohua

    2014-07-01

    A portable bioluminescence analyser for detecting the DNA sequence of genetically modified organisms (GMOs) was developed by using a photodiode (PD) array. Pyrosequencing on eight genes (zSSIIb, Bt11 and Bt176 gene of genetically modified maize; Lectin, 35S-CTP4, CP4EPSPS, CaMV35S promoter and NOS terminator of the genetically modified Roundup ready soya) was successfully detected with this instrument. The corresponding limit of detection (LOD) was 0.01% with 35 PCR cycles. The maize and soya available from three different provenances in China were detected. The results indicate that pyrosequencing using the small size of the detector is a simple, inexpensive, and reliable way in a farm/field test of GMO analysis.

  14. Overexpression of ARGOS Genes Modifies Plant Sensitivity to Ethylene, Leading to Improved Drought Tolerance in Both Arabidopsis and Maize.

    PubMed

    Shi, Jinrui; Habben, Jeffrey E; Archibald, Rayeann L; Drummond, Bruce J; Chamberlin, Mark A; Williams, Robert W; Lafitte, H Renee; Weers, Ben P

    2015-09-01

    Lack of sufficient water is a major limiting factor to crop production worldwide, and the development of drought-tolerant germplasm is needed to improve crop productivity. The phytohormone ethylene modulates plant growth and development as well as plant response to abiotic stress. Recent research has shown that modifying ethylene biosynthesis and signaling can enhance plant drought tolerance. Here, we report novel negative regulators of ethylene signal transduction in Arabidopsis (Arabidopsis thaliana) and maize (Zea mays). These regulators are encoded by the ARGOS gene family. In Arabidopsis, overexpression of maize ARGOS1 (ZmARGOS1), ZmARGOS8, Arabidopsis ARGOS homolog ORGAN SIZE RELATED1 (AtOSR1), and AtOSR2 reduced plant sensitivity to ethylene, leading to enhanced drought tolerance. RNA profiling and genetic analysis suggested that the ZmARGOS1 transgene acts between an ethylene receptor and CONSTITUTIVE TRIPLE RESPONSE1 in the ethylene signaling pathway, affecting ethylene perception or the early stages of ethylene signaling. Overexpressed ZmARGOS1 is localized to the endoplasmic reticulum and Golgi membrane, where the ethylene receptors and the ethylene signaling protein ETHYLENE-INSENSITIVE2 and REVERSION-TO-ETHYLENE SENSITIVITY1 reside. In transgenic maize plants, overexpression of ARGOS genes also reduces ethylene sensitivity. Moreover, field testing showed that UBIQUITIN1:ZmARGOS8 maize events had a greater grain yield than nontransgenic controls under both drought stress and well-watered conditions.

  15. Detection of Genetically Modified Food: Has Your Food Been Genetically Modified?

    ERIC Educational Resources Information Center

    Brandner, Diana L.

    2002-01-01

    Explains the benefits and risks of genetically-modified foods and describes methods for genetically modifying food. Presents a laboratory experiment using a polymerase chain reaction (PCR) test to detect foreign DNA in genetically-modified food. (Contains 18 references.) (YDS)

  16. Traceability of genetically modified organisms.

    PubMed

    Aarts, Henk J M; van Rie, Jean-Paul P F; Kok, Esther J

    2002-01-01

    EU regulations stipulate the labeling of food products containing genetically modified organisms (GMOs) unless the GMO content is due to adventitious and unintended 'contamination' and not exceeding the 1% level at ingredient basis. In addition, member states have to ensure full traceability at all stages of the placing on the market of GMOs. Both requirements ensure consumers 'right to know', facilitate enforcement of regulatory requirements and are of importance for environmental monitoring and postmarket surveillance. Besides administrative procedures, such as used in quality certification systems, the significance of adequate molecular methods becomes more and more apparent. During the last decade a considerable number of molecular methods have been developed and validated that enable the detection, identification and quantification of GMO impurities. Most of them rely on the PCR technology and can only detect one specific stretch of DNA. It can, however, be anticipated that in the near future the situation will become more complex. The number of GMO varieties, including 'stacked-gene' varieties, which will enter the European Market will increase and it is likely that these varieties will harbor more variable constructs. New tools will be necessary to keep up with these developments. One of the most promising techniques is microarray analysis. This technique enables the screening for a large number of different GMOs within a single experiment.

  17. Identification of genetic variants associated with maize flowering time using an extremely large multi-genetic background population

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flowering time is one of the major adaptive traits in domestication of maize and an important selection criterion in breeding. To detect more maize flowering time variants we evaluated flowering time traits using an extremely large multi- genetic background population that contained more than 8000 l...

  18. Genetic Analysis of the Morphological Differences between Maize and Teosinte

    PubMed Central

    Doebley, J.; Stec, A.

    1991-01-01

    Molecular marker loci were used to investigate the inheritance of morphological traits that distinguish maize (Zea mays ssp. mays) from a closely related wild relative, teosinte (Z. mays ssp. mexicana). Regression and interval mapping analyses gave largely congruent results concerning the numbers of loci controlling the morphological traits and the magnitudes of their effects; however, interval mapping tended to give larger estimates for the magnitudes of the effects of the morphological trait loci. This tendency was exaggerated for traits that were non-normally distributed. Variation for most inflorescence traits is controlled by one or two regions of the genome with large effects plus several other regions with relatively small effects. As such, the data are congruent with a mode of inheritance for most traits involving one or two major loci plus several minor loci. Regions of the genome with large effects on one trait consistently had smaller effects on several other traits, possibly as a result of pleiotropy. Most of the variation for the dramatic differences in inflorescence morphology between maize and teosinte is explained by five restricted regions of the genome. One of these regions encompasses a previously described gene, tb1 (teosinte branched), and the effects of this region on inflorescence architecture are similar to the known effects of tb1. Implications of this work for the genetic basis of morphological evolution in plants are discussed. PMID:1682215

  19. The genetics of leaf flecking in maize and its relationship to plant defense and disease resistance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Physiological/genetic leaf spotting, or flecking, is a mild lesion phenotype observed on the leaves of several commonly used maize inbred lines and has been anecdotally linked to enhanced broad-spectrum disease resistance. Flecking was assessed in the maize nested association mapping (NAM) populati...

  20. Influence of genetic background on anthocyanin and copigment composition and behavior during thermoalkaline processing of maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Visual color is a primary factor for foods purchase; identifying factors that influence in-situ color quality of pigmented maize during processing is important. We used 24 genetically distinct pigmented maize hybrids (red/blue, blue, red, and purple) to investigate the effect of pigment and copigme...

  1. Genetic, Genomic, and Breeding Approaches to Further Explore Kernel Composition Traits and Grain Yield in Maize

    ERIC Educational Resources Information Center

    Da Silva, Helena Sofia Pereira

    2009-01-01

    Maize ("Zea mays L.") is a model species well suited for the dissection of complex traits which are often of commercial value. The purpose of this research was to gain a deeper understanding of the genetic control of maize kernel composition traits starch, protein, and oil concentration, and also kernel weight and grain yield. Germplasm with…

  2. Genetic diversity of Hungarian Maize dwarf mosaic virus isolates.

    PubMed

    Gell, Gyöngyvér; Balázs, Ervin; Petrik, Kathrin

    2010-04-01

    The genetic diversity of the coat-protein (CP) region and the untranslated C-terminal region (3'UTR) of Maize dwarf mosaic virus (MDMV) was analyzed to evaluate the variability between isolates (inter-isolate sequence diversity). The results of inter-isolate sequence diversity analysis showed that the diversity of the MDMV CP gene is fairly high (p-distance: up to 0.136). During sequence analysis, a 13 amino-acid residue insertion and an 8 amino-acid residue deletion were found within the N-terminal region of the CP gene. The phylogenetic analysis showed that-unlike other potyvirus species in this subgroup-the MDMV isolates could not be distinguished on the basis of their host plants or geographic origins.

  3. Genetically modified pig models for human diseases.

    PubMed

    Fan, Nana; Lai, Liangxue

    2013-02-20

    Genetically modified animal models are important for understanding the pathogenesis of human disease and developing therapeutic strategies. Although genetically modified mice have been widely used to model human diseases, some of these mouse models do not replicate important disease symptoms or pathology. Pigs are more similar to humans than mice in anatomy, physiology, and genome. Thus, pigs are considered to be better animal models to mimic some human diseases. This review describes genetically modified pigs that have been used to model various diseases including neurological, cardiovascular, and diabetic disorders. We also discuss the development in gene modification technology that can facilitate the generation of transgenic pig models for human diseases.

  4. Genetic dissection of maize phenology using an intraspecific introgression library

    PubMed Central

    2011-01-01

    Background Collections of nearly isogenic lines where each line carries a delimited portion of a donor source genome into a common recipient genetic background are known as introgression libraries and have already shown to be instrumental for the dissection of quantitative traits. By means of marker-assisted backcrossing, we have produced an introgression library using the extremely early-flowering maize (Zea mays L.) variety Gaspé Flint and the elite line B73 as donor and recipient genotypes, respectively, and utilized this collection to investigate the genetic basis of flowering time and related traits of adaptive and agronomic importance in maize. Results The collection includes 75 lines with an average Gaspé Flint introgression length of 43.1 cM. The collection was evaluated for flowering time, internode length, number of ears, number of nodes (phytomeres), number of nodes above the ear, number and proportion of nodes below the ear and plant height. Five QTLs for flowering time were mapped, all corresponding to major QTLs for number of nodes. Three additional QTLs for number of nodes were mapped. Besides flowering time, the QTLs for number of nodes drove phenotypic variation for plant height and number of nodes below and above the top ear, but not for internode length. A number of apparently Mendelian-inherited phenotypes were also observed. Conclusions While the inheritance of flowering time was dominated by the well-known QTL Vgt1, a number of other important flowering time QTLs were identified and, thanks to the type of plant material here utilized, immediately isogenized and made available for fine mapping. At each flowering time QTL, early flowering correlated with fewer vegetative phytomeres, indicating the latter as a key developmental strategy to adapt the maize crop from the original tropical environment to the northern border of the temperate zone (southern Canada), where Gaspé Flint was originally cultivated. Because of the trait differences

  5. 78 FR 37201 - Pioneer Hi-Bred International, Inc.; Determination of Nonregulated Status of Maize Genetically...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-20

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF AGRICULTURE Animal and Plant Health Inspection Service Pioneer Hi-Bred International, Inc.; Determination of Nonregulated Status of Maize Genetically Engineered for Herbicide and Insect Resistance AGENCY: Animal...

  6. Assessing the possibility of genetically modified DNA transfer from GM feed to broiler, laying hen, pig and calf tissues.

    PubMed

    Sieradzki, Z; Mazur, M; Kwiatek, K; Swiatkiewicz, S; Swiatkiewicz, M; Koreleski, J; Hanczakowska, E; Arczewska-Włosek, A; Goldsztejn, M

    2013-01-01

    The aim of this study was to assess the possibility of genetically modified DNA transfer from feed containing RR soybean or/and MON810 maize to animal tissues, gut bacterial flora, food of animal origin, and the fate of GM DNA in the animal digestive tract. The experiment was carried out on broilers, laying hens, pigs and calves. All animals were divided into four groups: I--control group (non-modified feed), II--GM soybean group (non-modified maize, RR soybean), III--GM maize group (MON810 maize, non-modified soybean), and IV--GM maize and soybean group (MON810 maize, RR soybean). Samples of blood, organs, tissues, digesta from the gastrointestinal tract, and eggs were analysed for the presence of plant species specific genes, and transgenic sequences of CaMV 35S promoter and NOS terminator. PCR amplifications of these GM sequences were conducted to investigate the GM DNA transfer from feed to animal tissues and bacterial gut flora. In none of the analysed samples of blood, organs, tissues, eggs, excreta and bacterial DNA were plant reference genes or GM DNA found. A GM crop diet did not affect bacterial gut flora as regards diversity of bacteria species, quantity of particular bacteria species in the animal gut, or incorporation of transgenic DNA to the bacteria genome. It can be concluded that MON810 maize and RR soybean used for animal feeding are substantially equivalent to their conventional counterparts. Genetically modified DNA from MON810 maize and RR soybean is digested in the same way as plant DNA, with no probability of its transfer to animal tissues or gut bacterial flora.

  7. Testing for Genetically Modified Foods Using PCR

    ERIC Educational Resources Information Center

    Taylor, Ann; Sajan, Samin

    2005-01-01

    The polymerase chain reaction (PCR) is a Nobel Prize-winning technique that amplifies a specific segment of DNA and is commonly used to test for the presence of genetic modifications. Students use PCR to test corn meal and corn-muffin mixes for the presence of a promoter commonly used in genetically modified foods, the cauliflower mosaic virus 35S…

  8. Maize Seed Chitinase is Modified by a Protein Secreted by Bipolaris zeicola

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plants contain defense mechanisms that prevent infection by most fungi. Some specialized fungi have the ability to overcome plant defenses. The Zea mays (maize) seed chitinase ChitA has been previously reported as an antifungal protein. Here we report that ChitA is converted to a modified form by...

  9. Modification of recombinant maize ChitA chitinase by fungal chitinase-modifying proteins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In commercial maize, there are at least two different alleles of the chiA gene that encode alloforms of ChitA chitinase, a protein that is abundant in developing seed. Both known alloforms are modified by Bz-cmp, a protein secreted by the fungal pathogen Bipolaris zeicola. One alloform (ChitA-B73) i...

  10. [Risk assessment of genetically modified organisms].

    PubMed

    Costa, Thadeu Estevam Moreira Maramaldo; Dias, Aline Peçanha Muzy; Scheidegger, Erica Miranda Damasio; Marin, Victor Augustus

    2011-01-01

    Since the commercial approve in 1996, the global area of transgenic crops has raised more than 50 times. In the last two decades, governments have been planning strategies and protocols for safety assessment of food and feed genetically modified (GM). Evaluation of food safety should be taken on a case-by-case analysis depending on the specific traits of the modified crops and the changes introduced by the genetic modification, using for this the concept of substantial equivalence. This work presents approaches for the risk assessment of GM food, as well as some problems related with the genetic construction or even with the expression of the inserted gene.

  11. Safety assessment of genetically modified foods.

    PubMed

    Taylor, S L

    2001-12-01

    The development of novel foods produced through agricultural biotechnology is a complex three-stage process: gene discovery, line selection, and product advancement to commercialization. The safety of genetically modified foods is an integral part of the overall developmental process throughout all of the stages. In the discovery stage, the safety of the gene, its source, and the gene products must be considered. If any questions arise at this stage, these questions must be answered later in the developmental process. During the line selection stage, the genetically modified seed progresses through a variety of greenhouse and field trials. At this stage, the biological and agronomic equivalence of the genetically modified crop to its traditional counterpart must be compared. While the evaluations made during this stage are not specifically directed toward a safety assessment, many potential products with unusual characteristics are eliminated during this stage of development. However, the elimination of products with unusual agronomic or biological characteristics enhances the likelihood that a safe product will be generated. Finally, in the pre-commercialization stage, the genetically modified product undergoes a detailed safety assessment process. This process focuses on the safety of the gene products associated with the introduced gene and any other likely toxicological or anti-nutrient factors associated with the source of the novel gene and the crop to which it was introduced. The safety of the genetically modified product for both food and feed uses is considered. Thus far, all of the genetically modified products brought into the marketplace have been subjected to such an intensive safety assessment. The safety assessment data have been reviewed by regulatory authorities around the world. The current generation of genetically modified products are quite safe for human and feed animal consumption.

  12. Epigenetics: modifying the genetic blueprint.

    PubMed

    Eissenberg, Joel C

    2014-01-01

    The sequence of the human genome represents our genetic blueprint. While it is now possible to draw direct connections between specific DNA sequences and specific physical features and to predict disease risk, the effects of certain genes can be masked by a process called "epigenetics." Here, I summarize our current understanding of epigenetics and it affects gene expression, with impacts on health and aging.

  13. Genetic structure and diversity among maize inbred lines as inferred from DNA microsatellites.

    PubMed Central

    Liu, Kejun; Goodman, Major; Muse, Spencer; Smith, J Stephen; Buckler, Ed; Doebley, John

    2003-01-01

    Two hundred and sixty maize inbred lines, representative of the genetic diversity among essentially all public lines of importance to temperate breeding and many important tropical and subtropical lines, were assayed for polymorphism at 94 microsatellite loci. The 2039 alleles identified served as raw data for estimating genetic structure and diversity. A model-based clustering analysis placed the inbred lines in five clusters that correspond to major breeding groups plus a set of lines showing evidence of mixed origins. A "phylogenetic" tree was constructed to further assess the genetic structure of maize inbreds, showing good agreement with the pedigree information and the cluster analysis. Tropical and subtropical inbreds possess a greater number of alleles and greater gene diversity than their temperate counterparts. The temperate Stiff Stalk lines are on average the most divergent from all other inbred groups. Comparison of diversity in equivalent samples of inbreds and open-pollinated landraces revealed that maize inbreds capture <80% of the alleles in the landraces, suggesting that landraces can provide additional genetic diversity for maize breeding. The contributions of four different segments of the landrace gene pool to each inbred group's gene pool were estimated using a novel likelihood-based model. The estimates are largely consistent with known histories of the inbreds and indicate that tropical highland germplasm is poorly represented in maize inbreds. Core sets of inbreds that capture maximal allelic richness were defined. These or similar core sets can be used for a variety of genetic applications in maize. PMID:14704191

  14. Advances in Maize Genomics and Their Value for Enhancing Genetic Gains from Breeding

    PubMed Central

    Xu, Yunbi; Skinner, Debra J.; Wu, Huixia; Palacios-Rojas, Natalia; Araus, Jose Luis; Yan, Jianbing; Gao, Shibin; Warburton, Marilyn L.; Crouch, Jonathan H.

    2009-01-01

    Maize is an important crop for food, feed, forage, and fuel across tropical and temperate areas of the world. Diversity studies at genetic, molecular, and functional levels have revealed that, tropical maize germplasm, landraces, and wild relatives harbor a significantly wider range of genetic variation. Among all types of markers, SNP markers are increasingly the marker-of-choice for all genomics applications in maize breeding. Genetic mapping has been developed through conventional linkage mapping and more recently through linkage disequilibrium-based association analyses. Maize genome sequencing, initially focused on gene-rich regions, now aims for the availability of complete genome sequence. Conventional insertion mutation-based cloning has been complemented recently by EST- and map-based cloning. Transgenics and nutritional genomics are rapidly advancing fields targeting important agronomic traits including pest resistance and grain quality. Substantial advances have been made in methodologies for genomics-assisted breeding, enhancing progress in yield as well as abiotic and biotic stress resistances. Various genomic databases and informatics tools have been developed, among which MaizeGDB is the most developed and widely used by the maize research community. In the future, more emphasis should be given to the development of tools and strategic germplasm resources for more effective molecular breeding of tropical maize products. PMID:19688107

  15. Position of modifying groups on starch chains of octenylsuccinic anhydride-modified waxy maize starch.

    PubMed

    Bai, Yanjie; Kaufman, Rhett C; Wilson, Jeff D; Shi, Yong-Cheng

    2014-06-15

    Octenylsuccinic anhydride (OSA)-modified starches with a low (0.018) and high (0.092) degree of substitution (DS) were prepared from granular native waxy maize starch in aqueous slurry. The position of OS substituents along the starch chains was investigated by enzyme hydrolysis followed by chromatographic analysis. Native starch and two OS starches with a low and high DS had β-limit values of 55.9%, 52.8%, and 34.4%, respectively. The weight-average molecular weight of the β-limit dextrin from the OS starch with a low DS was close to that of the β-limit dextrin from native starch but lower than that of the β-limit dextrin from the OS starch with a high DS. Debranching of OS starches was incomplete compared with native starch. OS groups in the OS starch with a low DS were located on the repeat units near the branching points, whereas the OS substituents in the OS starch with a high DS occurred both near the branching points and the non-reducing ends.

  16. Electron beam technology for modifying the functional properties of maize starch

    NASA Astrophysics Data System (ADS)

    Nemţanu, M. R.; Minea, R.; Kahraman, K.; Koksel, H.; Ng, P. K. W.; Popescu, M. I.; Mitru, E.

    2007-09-01

    Maize starch is a versatile biopolymer with a wide field of applications (e.g. foods, pharmaceutical products, adhesives, etc.). Nowadays there is a continuous and intensive search for new methods and techniques to modify its functional properties due to the fact that native form of starch may exhibit some disadvantages in certain applications. Radiation technology is frequently used to change the properties of different polymeric materials. Thus, the goal of the work is to discuss the application of accelerated electron beams on maize starch in the view of changing some of its functional properties. Maize starch has been irradiated with doses up to 52.15 kGy by using electron beam technology and the modifications of differential scanning calorimetry (DSC) and pasting characteristics, paste clarity, freezing and thawing stability as well as colorimetric characteristics have been investigated. The results of the study revealed that the measured properties can be modified by electron beam treatment and, therefore, this method can be an efficient and ecological alternative to obtain modified maize starch.

  17. [Genetically modified food--unnecessary controversy?].

    PubMed

    Tchórz, Michał; Radoniewicz-Chagowska, Anna; Lewandowska-Stanek, Hanna; Szponar, Elzbieta; Szponar, Jarosław

    2012-01-01

    Fast development of genetic engineering and biotechnology allows use of genetically modified organisms (GMO) more and more in different branches of science and economy. Every year we can see an increase of food amount produced with the use of modification of genetic material. In our supermarkets we can find brand new types of plants, products including genetically modified ingredients or meat from animals fed with food containing GMO. This article presents general information about genetically modified organisms, it also explains the range of genetic manipulation, use of newly developed products and current field area for GMO in the world. Based on scientific data the article presents benefits from development of biotechnology in reference to modified food. It also presents the voice of skeptics who are extremely concerned about the impact of those organisms on human health and natural environment. Problems that appear or can appear as a result of an increase of GMO are very important not only from a toxicologist's or a doctor's point of view but first of all from the point of view of ordinary consumers--all of us.

  18. Genetic, evoluntionary and plant breedinginsights from the domestication of maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The natural history of maize began nine thousand years ago when Mexican farmers started to collect the seeds of the wild grass, teosinte. Invaluable as a food source, maize permeated Mexican culture and religion. Its domestication eventually led to its adoption as a model organism, aided in large pa...

  19. Genetically Modified Foods and Consumer Perspective.

    PubMed

    Boccia, Flavio; Sarnacchiaro, Pasquale

    2015-01-01

    Genetically modified food is able to oppose the world's hunger and preserve the environment, even if the patents in this matter are symptomatic of several doubts. And also, transgenic consumption causes problems and skepticism among consumers in several European countries, but above all in Italy, where there is a strong opposition over recent years. So, the present study conducted a research to study the consumption of genetically modified food products by Italian young generation. This research presented the following purposes: firstly, to analyze genetically modified products' consumption among a particular category of consumers; secondly, to implement a quantitative model to understand behaviour about this particular kind of consumption and identify the factors that determine their purchase. The proposed model shows that transgenic consumption is especially linked to knowledge and impact on environment and mankind's health.

  20. [Genetically modified food and allergies - an update].

    PubMed

    Niemann, Birgit; Pöting, Annette; Braeuning, Albert; Lampen, Alfonso

    2016-07-01

    Approval by the European Commission is mandatory for placing genetically modified plants as food or feed on the market in member states of the European Union (EU). The approval is preceded by a safety assessment based on the guidance of the European Food Safety Authority EFSA. The assessment of allergenicity of genetically modified plants and their newly expressed proteins is an integral part of this assessment process. Guidance documents for the assessment of allergenicity are currently under revision. For this purpose, an expert workshop was conducted in Brussels on June 17, 2015. There, methodological improvements for the assessment of coeliac disease-causing properties of proteins, as well as the use of complex models for in vitro digestion of proteins were discussed. Using such techniques a refinement of the current, proven system of allergenicity assessment of genetically modified plants can be achieved.

  1. Genetically modified animals and pharmacological research.

    PubMed

    Wells, Dominic J

    2010-01-01

    This chapter reviews the use of genetically modified animals and the increasingly detailed knowledge of the genomes of the domestic species. The different approaches to genetic modification are outlined as are the advantages and disadvantages of the techniques in different species. Genetically modified mice have been fundamental in understanding gene function and in generating affordable models of human disease although these are not without their drawbacks. Transgenic farm animals have been developed for nutritionally enhanced food, disease resistance and xenografting. Transgenic rabbits, goats, sheep and cows have been developed as living bioreactors producing potentially high value biopharmaceuticals, commonly referred to as "pharming". Domestic animals are also important as a target as well as for testing genetic-based therapies for both inherited and acquired disease. This latter field may be the most important of all, in the future development of novel therapies.

  2. Genetically modified pig models for neurodegenerative disorders.

    PubMed

    Holm, Ida E; Alstrup, Aage Kristian Olsen; Luo, Yonglun

    2016-01-01

    Increasing incidence of neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease has become one of the most challenging health issues in ageing humans. One approach to combat this is to generate genetically modified animal models of neurodegenerative disorders for studying pathogenesis, prognosis, diagnosis, treatment, and prevention. Owing to the genetic, anatomic, physiologic, pathologic, and neurologic similarities between pigs and humans, genetically modified pig models of neurodegenerative disorders have been attractive large animal models to bridge the gap of preclinical investigations between rodents and humans. In this review, we provide a neuroanatomical overview in pigs and summarize and discuss the generation of genetically modified pig models of neurodegenerative disorders including Alzheimer's diseases, Huntington's disease, Parkinson's disease, amyotrophic lateral sclerosis, spinal muscular atrophy, and ataxia-telangiectasia. We also highlight how non-invasive bioimaging technologies such as positron emission tomography (PET), computer tomography (CT), and magnetic resonance imaging (MRI), and behavioural testing have been applied to characterize neurodegenerative pig models. We further propose a multiplex genome editing and preterm recloning (MAP) approach by using the rapid growth of the ground-breaking precision genome editing technology CRISPR/Cas9 and somatic cell nuclear transfer (SCNT). With this approach, we hope to shorten the temporal requirement in generating multiple transgenic pigs, increase the survival rate of founder pigs, and generate genetically modified pigs that will more closely resemble the disease-causing mutations and recapitulate pathological features of human conditions.

  3. Ssr analysis for genetic structure and diversity determination of maize local populations from former Yugoslavia territories.

    PubMed

    Ignjatović-Micić, D; Drinić, S Mladenović; Nikolić, A; Lazić-Jancić, V

    2008-11-01

    A collection of 2178 local populations from ex-Yugoslavia territories is maintained in Maize Research Institute (MRI) gene bank. These populations were characterized mainly by morphological markers. In this work 21 local populations belonging to seven different agro-ecological groups have been subjected to SSR analysis using a DNA-pooling strategy. The objective of this work was to develop genetic fingerprints for characterization, identification and classification of the populations, as well as for estimation of their genetic diversity. Also, a DNA-pooling strategy was employed with the aim to certify if it could be applied for population analysis with SSR markers. Statistical analysis of 25 informative SSR primers revealing 224 alleles (bands) showed that the average within-population mean number of alleles was 2.55, the average values for total and within-population diversity were 0.784 and 0.502, respectively and G(ST) value was 0.360. Genetic distance values calculated using Modified Rogers' Distance were in the range from 0.35 to 0.60. The silver staining method of DNA used for bulked samples showed some weakness that could be overcome with a more sensitive staining method. Nevertheless, the results in this work indicate that the SSR analysis of bulks could be used for characterizing a large number of populations in gene banks.

  4. An event-specific DNA microarray to identify genetically modified organisms in processed foods.

    PubMed

    Kim, Jae-Hwan; Kim, Su-Youn; Lee, Hyungjae; Kim, Young-Rok; Kim, Hae-Yeong

    2010-05-26

    We developed an event-specific DNA microarray system to identify 19 genetically modified organisms (GMOs), including two GM soybeans (GTS-40-3-2 and A2704-12), thirteen GM maizes (Bt176, Bt11, MON810, MON863, NK603, GA21, T25, TC1507, Bt10, DAS59122-7, TC6275, MIR604, and LY038), three GM canolas (GT73, MS8xRF3, and T45), and one GM cotton (LLcotton25). The microarray included 27 oligonucleotide probes optimized to identify endogenous reference targets, event-specific targets, screening targets (35S promoter and nos terminator), and an internal target (18S rRNA gene). Thirty-seven maize-containing food products purchased from South Korean and US markets were tested for the presence of GM maize using this microarray system. Thirteen GM maize events were simultaneously detected using multiplex PCR coupled with microarray on a single chip, at a limit of detection of approximately 0.5%. Using the system described here, we detected GM maize in 11 of the 37 food samples tested. These results suggest that an event-specific DNA microarray system can reliably detect GMOs in processed foods.

  5. Genetically Modified Plants: Public and Scientific Perceptions

    PubMed Central

    2013-01-01

    The potential of genetically modified plants to meet the requirements of growing population is not being recognized at present. This is a consequence of concerns raised by the public and the critics about their applications and release into the environment. These include effect on human health and environment, biosafety, world trade monopolies, trustworthiness of public institutions, integrity of regulatory agencies, loss of individual choice, and ethics as well as skepticism about the real potential of the genetically modified plants, and so on. Such concerns are enormous and prevalent even today. However, it should be acknowledged that most of them are not specific for genetically modified plants, and the public should not forget that the conventionally bred plants consumed by them are also associated with similar risks where no information about the gene(s) transfer is available. Moreover, most of the concerns are hypothetical and lack scientific background. Though a few concerns are still to be disproved, it is viewed that, with proper management, these genetically modified plants have immense potential for the betterment of mankind. In the present paper, an overview of the raised concerns and wherever possible reasons assigned to explain their intensity or unsuitability are reviewed. PMID:25937981

  6. Genetically engineered crops and pesticide use in U.S. maize and soybeans

    PubMed Central

    Perry, Edward D.; Ciliberto, Federico; Hennessy, David A.; Moschini, GianCarlo

    2016-01-01

    The widespread adoption of genetically engineered (GE) crops has clearly led to changes in pesticide use, but the nature and extent of these impacts remain open questions. We study this issue with a unique, large, and representative sample of plot-level choices made by U.S. maize and soybean farmers from 1998 to 2011. On average, adopters of GE glyphosate-tolerant (GT) soybeans used 28% (0.30 kg/ha) more herbicide than nonadopters, adopters of GT maize used 1.2% (0.03 kg/ha) less herbicide than nonadopters, and adopters of GE insect-resistant (IR) maize used 11.2% (0.013 kg/ha) less insecticide than nonadopters. When pesticides are weighted by the environmental impact quotient, however, we find that (relative to nonadopters) GE adopters used about the same amount of soybean herbicides, 9.8% less of maize herbicides, and 10.4% less of maize insecticides. In addition, the results indicate that the difference in pesticide use between GE and non-GE adopters has changed significantly over time. For both soybean and maize, GT adopters used increasingly more herbicides relative to nonadopters, whereas adopters of IR maize used increasingly less insecticides. The estimated pattern of change in herbicide use over time is consistent with the emergence of glyphosate weed resistance. PMID:27652335

  7. High-Throughput Phenotyping and QTL Mapping Reveals the Genetic Architecture of Maize Plant Growth.

    PubMed

    Zhang, Xuehai; Huang, Chenglong; Wu, Di; Qiao, Feng; Li, Wenqiang; Duan, Lingfeng; Wang, Ke; Xiao, Yingjie; Chen, Guoxing; Liu, Qian; Xiong, Lizhong; Yang, Wanneng; Yan, Jianbing

    2017-03-01

    With increasing demand for novel traits in crop breeding, the plant research community faces the challenge of quantitatively analyzing the structure and function of large numbers of plants. A clear goal of high-throughput phenotyping is to bridge the gap between genomics and phenomics. In this study, we quantified 106 traits from a maize (Zea mays) recombinant inbred line population (n = 167) across 16 developmental stages using the automatic phenotyping platform. Quantitative trait locus (QTL) mapping with a high-density genetic linkage map, including 2,496 recombinant bins, was used to uncover the genetic basis of these complex agronomic traits, and 988 QTLs have been identified for all investigated traits, including three QTL hotspots. Biomass accumulation and final yield were predicted using a combination of dissected traits in the early growth stage. These results reveal the dynamic genetic architecture of maize plant growth and enhance ideotype-based maize breeding and prediction.

  8. New Insights into the Genetics of in Vivo Induction of Maternal Haploids, the Backbone of Doubled Haploid Technology in Maize

    PubMed Central

    Prigge, Vanessa; Xu, Xiaowei; Li, Liang; Babu, Raman; Chen, Shaojiang; Atlin, Gary N.; Melchinger, Albrecht E.

    2012-01-01

    Haploids and doubled haploid (DH) inbred lines have become an invaluable tool for maize genetic research and hybrid breeding, but the genetic basis of in vivo induction of maternal haploids is still unknown. This is the first study reporting comparative quantitative trait locus (QTL) analyses of this trait in maize. We determined haploid induction rates (HIR) in testcrosses of a total of 1061 progenies of four segregating populations involving two temperate haploid inducers, UH400 (HIR = 8%) and CAUHOI (HIR = 2%), one temperate and two tropical inbreds with HIR = 0%, and up to three generations per population. Mean HIR of the populations ranged from 0.6 to 5.2% and strongly deviated from the midparent values. One QTL (qhir1) explaining up to p^=66% of the genetic variance was detected in bin 1.04 in the three populations involving a noninducer parent and the HIR-enhancing allele was contributed by UH400. Segregation ratios of loci in bin 1.04 were highly distorted against the UH400 allele in these three populations, suggesting that transmission failure of the inducer gamete and haploid induction ability are related phenomena. In the CAUHOI × UH400 population, seven QTL were identified on five chromosomes, with qhir8 on chromosome 9 having p^>20% in three generations of this cross. The large-effect QTL qhir1 and qhir8 will likely become fixed quickly during inducer development due to strong selection pressure applied for high HIR. Hence, marker-based pyramiding of small-effect and/or modifier QTL influencing qhir1 and qhir8 may help to further increase HIR in maize. We propose a conceptual genetic framework for inheritance of haploid induction ability, which is also applicable to other dichotomous traits requiring progeny testing, and discuss the implications of our results for haploid inducer development. PMID:22135357

  9. Genetic Analysis of Teosinte Alleles for Kernel Composition Traits in Maize.

    PubMed

    Karn, Avinash; Gillman, Jason D; Flint-Garcia, Sherry A

    2017-02-10

    Teosinte (Zea mays ssp. parviglumis) is the wild ancestor of modern maize (Zea mays ssp. mays). Teosinte contains greater genetic diversity compared to maize inbreds and landraces, but its use is limited by insufficient genetic resources to evaluate its value. A population of teosinte near isogenic lines (teosinte NILs) was previously developed to broaden the resources for genetic diversity of maize, and to discover novel alleles for agronomic and domestication traits. The 961 teosinte NILs were developed by backcrossing ten geographically diverse parviglumis accessions into the B73 (reference genome inbred) background. The NILs were grown in two replications in 2009 and 2010 in Columbia, Missouri and Aurora, New York, respectively, and Near Infrared Reflectance (NIR) spectroscopy and Nuclear Magnetic Resonance (NMR) calibrations were developed and used to rapidly predict total kernel starch, protein and oil content on a dry matter basis in bulk whole grains of teosinte NILs. Our joint-linkage quantitative trait locus (QTL) mapping analysis identified two starch, three protein and six oil QTLs, which collectively explained 18%, 23% and 45% of the total variation, respectively. A range of strong additive allelic effects for kernel starch, protein and oil content were identified relative to the B73 allele. Our results support our hypothesis that teosinte harbors stronger alleles for kernel composition traits than maize, and that teosinte can be exploited for the improvement of kernel composition traits in modern maize germplasm.

  10. Genetic Analysis of Teosinte Alleles for Kernel Composition Traits in Maize

    PubMed Central

    Karn, Avinash; Gillman, Jason D.; Flint-Garcia, Sherry A.

    2017-01-01

    Teosinte (Zea mays ssp. parviglumis) is the wild ancestor of modern maize (Zea mays ssp. mays). Teosinte contains greater genetic diversity compared with maize inbreds and landraces, but its use is limited by insufficient genetic resources to evaluate its value. A population of teosinte near isogenic lines (NILs) was previously developed to broaden the resources for genetic diversity of maize, and to discover novel alleles for agronomic and domestication traits. The 961 teosinte NILs were developed by backcrossing 10 geographically diverse parviglumis accessions into the B73 (reference genome inbred) background. The NILs were grown in two replications in 2009 and 2010 in Columbia, MO and Aurora, NY, respectively, and near infrared reflectance spectroscopy and nuclear magnetic resonance calibrations were developed and used to rapidly predict total kernel starch, protein, and oil content on a dry matter basis in bulk whole grains of teosinte NILs. Our joint-linkage quantitative trait locus (QTL) mapping analysis identified two starch, three protein, and six oil QTL, which collectively explained 18, 23, and 45% of the total variation, respectively. A range of strong additive allelic effects for kernel starch, protein, and oil content were identified relative to the B73 allele. Our results support our hypothesis that teosinte harbors stronger alleles for kernel composition traits than maize, and that teosinte can be exploited for the improvement of kernel composition traits in modern maize germplasm. PMID:28188181

  11. [Genetic diversity of starch synthesis genes of Chinese maize (Zea mays L.) with SNAPs].

    PubMed

    Cao, Wen-Bo; Zheng, Lu-Lu; Zhang, Zheng-Feng; Li, Xue-Bao

    2009-01-01

    Analysis of genetic diversity in maize populations is a very important step for understanding genetic structure and subsequently for genetic manipulations in maize breeding. Sh2, Bt2, Sh1, Wx1, Ae1 and Su1 involved in starch biosynthesis are important genes associated with yield and quality traits in maize breeding programs. In this study, genetic diversity of these six genes in 67 Chinese elite maize inbred lines was measured using single-nucleotide amplified polymorphisms (SNAPs). The results indicated that the number of haplotypes of each gene and population was far less than theoretically expected 2(n) (n = the number of the SNAPs). Phenetic clustering analysis showed that the kernel phonetic (semi-) dent and (semi-) flint lines were belong to distinct subclusters based on haplotypes of SNAPs, with a few exceptions. In addition, the genetic origin of these maize inbred lines was associated with the clustered subgroups. Intragenic linkage disequilibrium (LD) was observed in some of the SNAPs in Bt2, Sh1 and Ae1, while intergenic LD was observed in some of the SNAPs in Bt2, Sh1 and Su1. Association study of kernel phenotypes and SNAP haplotypes showed that the (semi-) dent and (semi-) flint lines had the common haplotype of TA and CC at two SNAP sites in Bt2 (Bt2-2 and Bt2-5), respectively. Two haplotypes of ATGT and GTGC at four SNAP sites in Sh1 (Sh1-2, Sh1-3, Sh1-4 and Sh1-5) were associated with temperature and tropical origin of the maize inbred lines, respectively.

  12. Genetic Variability and Geographical Distribution of Mycotoxigenic Fusarium verticillioides Strains Isolated from Maize Fields in Texas

    PubMed Central

    Ortiz, Carlos S.; Richards, Casey; Terry, Ashlee; Parra, Joselyn; Shim, Won-Bo

    2015-01-01

    Maize is the dominant cereal crop produced in the US. One of the main fungal pathogens of maize is Fusarium verticillioides, the causative agent of ear and stalk rots. Significantly, the fungus produces a group of mycotoxins - fumonisins - on infested kernels, which have been linked to various illnesses in humans and animals. Nonetheless, durable resistance against F. verticillioides in maize is not currently available. In Texas, over 2.1 million acres of maize are vulnerable to fumonisin contamination, but understanding of the distribution of toxigenic F. verticillioides in maize-producing areas is currently lacking. Our goal was to investigate the genetic variability of F. verticillioides in Texas with an emphasis on fumonisin trait and geographical distribution. A total of 164 F. verticillioides cultures were isolated from 65 maize-producing counties. DNA from each isolate was extracted and analyzed by PCR for the presence of FUM1- a key fumonisin biosynthesis gene - and mating type genes. Results showed that all isolates are in fact F. verticillioides capable of producing fumonisins with a 1:1 mating-type gene ratio in the population. To further study the genetic diversity of the population, isolates were analyzed using RAPD fingerprinting. Polymorphic markers were identified and the analysis showed no clear correlation between the RAPD profile of the isolates and their corresponding geographical origin. Our data suggest the toxigenic F. verticillioides population in Texas is widely distributed wherever maize is grown. We also hypothesize that the population is fluid, with active movement and genetic recombination occurring in the field. PMID:26361468

  13. Substantial equivalence of antinutrients and inherent plant toxins in genetically modified novel foods.

    PubMed

    Novak, W K; Haslberger, A G

    2000-06-01

    For a safety evaluation of foodstuff derived from genetically modified crops, the concept of the substantial equivalence of modified organisms with their parental lines is used following an environmental safety evaluation. To assess the potential pleiotropic effect of genetic modifications on constituents of modified crops data from US and EC documents were investigated with regard to inherent plant toxins and antinutrients. Analysed were documents of rape (glucosinolates, phytate), maize (phytate), tomato (tomatine, solanine, chaconine, lectins, oxalate), potato (solanine, chaconine, protease-inhibitors, phenols) and soybean (protease-inhibitors, lectins, isoflavones, phytate). In several documents used for notifications no declarations even on essential inherent plant toxins and antinutrients could be found, for instance data on phytate in modified maize were provided only in one of four documents. Significant variations in the contents of these compounds in parental and modified plants especially due to environmental influences were observed: drought stress, for example, was made responsible for significantly increased glucosinolate levels of up to 72.6micromol/g meal in modified and parental rape plants in field trials compared to recommended standard concentrations of less than 30micromol/g. Taking into account these wide natural variations generally the concentrations of inherent plant toxins and antinutrients in modified products were in the range of the concentrations in parental organisms. The results presented indicate that the concept of the substantial equivalence is useful for the risk assessment of genetically modified organisms (GMOs) used for novel foods but possible environmental influences on constituents of modified crops need more attention. Consistent guidelines, specifying data of relevant compounds which have to be provided for notification documents of specific organisms have to be established. Because of the importance of inherent plant

  14. [Genetically modified food--great unknown].

    PubMed

    Cichosz, G; Wiackowski, S K

    2012-08-01

    Genetically modified food (GMF) creates evident threat to consumers' health. In spite of assurances of biotechnologists, DNA of transgenic plants is instable, so, synthesis of foreign, allergenic proteins is possible. Due to high trypsin inhibitor content the GMF is digested much more slowly what, alike Bt toxin presence, increases probability of alimentary canal diseases. Next threats are bound to the presence of fitoestrogens and residues of Roundup pesticide, that can diminish reproductiveness; and even lead to cancerogenic transformation through disturbance of human hormonal metabolism. In spite of food producers and distributors assurances that food made of GMF raw materials is marked, de facto consumers have no choice. Moreover, along the food law products containing less than 0.9% of GMF protein are not included into genetically modified food.

  15. Genetically modified pigs to model human diseases.

    PubMed

    Flisikowska, Tatiana; Kind, Alexander; Schnieke, Angelika

    2014-02-01

    Genetically modified mice are powerful tools to investigate the molecular basis of many human diseases. Mice are, however, of limited value for preclinical studies, because they differ significantly from humans in size, general physiology, anatomy and lifespan. Considerable efforts are, thus, being made to develop alternative animal models for a range of human diseases. These promise powerful new resources that will aid the development of new diagnostics, medicines and medical procedures. Here, we provide a comprehensive review of genetically modified porcine models described in the scientific literature: various cancers, cystic fibrosis, Duchenne muscular dystrophy, autosomal polycystic kidney disease, Huntington’s disease, spinal muscular atrophy, haemophilia A, X-linked severe combined immunodeficiency, retinitis pigmentosa, Stargardt disease, Alzheimer’s disease, various forms of diabetes mellitus and cardiovascular diseases.

  16. Are genetically modified plants useful and safe?

    PubMed

    Weil, Jacques-Henry

    2005-01-01

    So far, plants have been genetically modified essentially to achieve resistance to herbicides, or to pathogens (mainly insects, or viruses), but resistance to abiotic stresses (such as cold, heat, drought, or salt) is also being studied. Genetically modified (GM) plants with improved nutritional qualities have more recently been developed, such as plants containing higher proportions of unsaturated fatty acids (omega-3 and omega-6) in their oil (to prevent cardio-vascular diseases), or containing beta-carotene as in the golden rice (to prevent vitamin A deficiency). Possible risks for human health (such as the production of allergenic proteins), or for the environment (such as the appearance of superweeds as a result from gene flow), should be carefully studied, and a science-based assessment of benefits vs. risks should be made on a case by case basis, both for GM plants and for plants obtained by conventional breeding methods.

  17. Computational identification of genetic subnetwork modules associated with maize defense response to Fusarium verticillioides

    PubMed Central

    2015-01-01

    Background Maize, a crop of global significance, is vulnerable to a variety of biotic stresses resulting in economic losses. Fusarium verticillioides (teleomorph Gibberella moniliformis) is one of the key fungal pathogens of maize, causing ear rots and stalk rots. To better understand the genetic mechanisms involved in maize defense as well as F. verticillioides virulence, a systematic investigation of the host-pathogen interaction is needed. The aim of this study was to computationally identify potential maize subnetwork modules associated with its defense response against F. verticillioides. Results We obtained time-course RNA-seq data from B73 maize inoculated with wild type F. verticillioides and a loss-of-virulence mutant, and subsequently established a computational pipeline for network-based comparative analysis. Specifically, we first analyzed the RNA-seq data by a cointegration-correlation-expression approach, where maize genes were jointly analyzed with known F. verticillioides virulence genes to find candidate maize genes likely associated with the defense mechanism. We predicted maize co-expression networks around the selected maize candidate genes based on partial correlation, and subsequently searched for subnetwork modules that were differentially activated when inoculated with two different fungal strains. Based on our analysis pipeline, we identified four potential maize defense subnetwork modules. Two were directly associated with maize defense response and were associated with significant GO terms such as GO:0009817 (defense response to fungus) and GO:0009620 (response to fungus). The other two predicted modules were indirectly involved in the defense response, where the most significant GO terms associated with these modules were GO:0046914 (transition metal ion binding) and GO:0046686 (response to cadmium ion). Conclusion Through our RNA-seq data analysis, we have shown that a network-based approach can enhance our understanding of the

  18. The physical and genetic framework of the maize B73 genome.

    PubMed

    Wei, Fusheng; Zhang, Jianwei; Zhou, Shiguo; He, Ruifeng; Schaeffer, Mary; Collura, Kristi; Kudrna, David; Faga, Ben P; Wissotski, Marina; Golser, Wolfgang; Rock, Susan M; Graves, Tina A; Fulton, Robert S; Coe, Ed; Schnable, Patrick S; Schwartz, David C; Ware, Doreen; Clifton, Sandra W; Wilson, Richard K; Wing, Rod A

    2009-11-01

    Maize is a major cereal crop and an important model system for basic biological research. Knowledge gained from maize research can also be used to genetically improve its grass relatives such as sorghum, wheat, and rice. The primary objective of the Maize Genome Sequencing Consortium (MGSC) was to generate a reference genome sequence that was integrated with both the physical and genetic maps. Using a previously published integrated genetic and physical map, combined with in-coming maize genomic sequence, new sequence-based genetic markers, and an optical map, we dynamically picked a minimum tiling path (MTP) of 16,910 bacterial artificial chromosome (BAC) and fosmid clones that were used by the MGSC to sequence the maize genome. The final MTP resulted in a significantly improved physical map that reduced the number of contigs from 721 to 435, incorporated a total of 8,315 mapped markers, and ordered and oriented the majority of FPC contigs. The new integrated physical and genetic map covered 2,120 Mb (93%) of the 2,300-Mb genome, of which 405 contigs were anchored to the genetic map, totaling 2,103.4 Mb (99.2% of the 2,120 Mb physical map). More importantly, 336 contigs, comprising 94.0% of the physical map ( approximately 1,993 Mb), were ordered and oriented. Finally we used all available physical, sequence, genetic, and optical data to generate a golden path (AGP) of chromosome-based pseudomolecules, herein referred to as the B73 Reference Genome Sequence version 1 (B73 RefGen_v1).

  19. Genetically Modified Foods and Social Concerns

    PubMed Central

    Maghari, Behrokh Mohajer; Ardekani, Ali M.

    2011-01-01

    Biotechnology is providing us with a wide range of options for how we can use agricultural and commercial forestry lands. The cultivation of genetically modified (GM) crops on millions of hectares of lands and their injection into our food chain is a huge global genetic experiment involving all living beings. Considering the fast pace of new advances in production of genetically modified crops, consumers, farmers and policymakers worldwide are challenged to reach a consensus on a clear vision for the future of world food supply. The current food biotechnology debate illustrates the serious conflict between two groups: 1) Agri-biotech investors and their affiliated scientists who consider agricultural biotechnology as a solution to food shortage, the scarcity of environmental resources and weeds and pests infestations; and 2) independent scientists, environmentalists, farmers and consumers who warn that genetically modified food introduces new risks to food security, the environment and human health such as loss of biodiversity; the emergence of superweeds and superpests; the increase of antibiotic resistance, food allergies and other unintended effects. This article reviews major viewpoints which are currently debated in the food biotechnology sector in the world. It also lays the ground-work for deep debate on benefits and risks of Biotech-crops for human health, ecosystems and biodiversity. In this context, although some regulations exist, there is a need for continuous vigilance for all countries involved in producing genetically engineered food to follow the international scientific bio-safety testing guidelines containing reliable pre-release experiments and post-release track of transgenic plants to protect public health and avoid future environmental harm. PMID:23408723

  20. Genetically modified foods and social concerns.

    PubMed

    Maghari, Behrokh Mohajer; Ardekani, Ali M

    2011-07-01

    Biotechnology is providing us with a wide range of options for how we can use agricultural and commercial forestry lands. The cultivation of genetically modified (GM) crops on millions of hectares of lands and their injection into our food chain is a huge global genetic experiment involving all living beings. Considering the fast pace of new advances in production of genetically modified crops, consumers, farmers and policymakers worldwide are challenged to reach a consensus on a clear vision for the future of world food supply. The current food biotechnology debate illustrates the serious conflict between two groups: 1) Agri-biotech investors and their affiliated scientists who consider agricultural biotechnology as a solution to food shortage, the scarcity of environmental resources and weeds and pests infestations; and 2) independent scientists, environmentalists, farmers and consumers who warn that genetically modified food introduces new risks to food security, the environment and human health such as loss of biodiversity; the emergence of superweeds and superpests; the increase of antibiotic resistance, food allergies and other unintended effects. This article reviews major viewpoints which are currently debated in the food biotechnology sector in the world. It also lays the ground-work for deep debate on benefits and risks of Biotech-crops for human health, ecosystems and biodiversity. In this context, although some regulations exist, there is a need for continuous vigilance for all countries involved in producing genetically engineered food to follow the international scientific bio-safety testing guidelines containing reliable pre-release experiments and post-release track of transgenic plants to protect public health and avoid future environmental harm.

  1. Genetically modified pigs for medicine and agriculture.

    PubMed

    Prather, Randall S; Shen, Miaoda; Dai, Yifan

    2008-01-01

    The ability to genetically modify pigs has enabled scientists to create pigs that are beneficial to humans in ways that were previously unimaginable. Improvements in the methods to make genetic modifications have opened up the possibilities of introducing transgenes, knock-outs and knock-ins with precision. The benefits to medicine include the production of pharmaceuticals, the provision of organs for xenotransplantation into humans, and the development of models of human diseases. The benefits to agriculture include resistance to disease, altering the carcass composition such that it is healthier to consume, improving the pig's resistance to heat stress, and protecting the environment. Additional types of genetic modifications will likely provide animals with characteristics that will benefit humans in currently unimagined ways.

  2. Earthworms modify microbial community structure and accelerate maize stover decomposition during vermicomposting.

    PubMed

    Chen, Yuxiang; Zhang, Yufen; Zhang, Quanguo; Xu, Lixin; Li, Ran; Luo, Xiaopei; Zhang, Xin; Tong, Jin

    2015-11-01

    In the present study, maize stover was vermicomposted with the epigeic earthworm Eisenia fetida. The results showed that, during vermicomposting process, the earthworms promoted decomposition of maize stover. Analysis of microbial communities of the vermicompost by high-throughput pyrosequencing showed more complex bacterial community structure in the substrate treated by the earthworms than that in the control group. The dominant microbial genera in the treatment with the earthworms were Pseudoxanthomonas, Pseudomonas, Arthrobacter, Streptomyces, Cryptococcus, Guehomyces, and Mucor. Compared to the control group, the relative abundance of lignocellulose degradation microorganisms increased. The results indicated that the earthworms modified the structure of microbial communities during vermicomposting process, activated the growth of lignocellulose degradation microorganisms, and triggered the lignocellulose decomposition.

  3. Genetic characterization of the North Carolina State University maize lines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Since 1980, 150 North Carolina State University maize inbreds have been developed and released on the basis of superior performance for topcross yield and other traits of agronomic importance. During this time there has been great emphasis placed on breeding with exotic germplasm, with 86 NCSU inbr...

  4. Genetic and biochemical analysis of iron bioavailability in maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize is a major cereal crop widely consumed in developing countries, which have a high prevalence of iron (Fe) deficiency including anemia. The major cause of Fe deficiency in these countries is inadequate intake of bioavailable Fe, of which poverty is a major contributing factor. Therefore, biofor...

  5. Genetic and biochemical analysis of iron bioavailability in maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize is a major cereal crop widely consumed in developing countries, which have a high prevalence of iron (Fe) deficiency including anemia. The major cause of Fe deficiency in these countries is an inadequate intake of bioavailable Fe, of which poverty is a major contributing factor. Therefore, b...

  6. Bulk genetic characterization of Ghanaian maize landraces using microsatellite markers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize (Zea mays) was first introduced into Ghana over 5 centuries ago and remains the most important cereal staple, grown in all agro-ecologies across the country. Yield from farmers’ fields are low, which is attributed in part to farmer’s preferences and/or reliance on local landraces for cultivati...

  7. Genetic diversity and population structure of native maize populations in Latin America and the Caribbean.

    PubMed

    Bedoya, Claudia A; Dreisigacker, Susanne; Hearne, Sarah; Franco, Jorge; Mir, Celine; Prasanna, Boddupalli M; Taba, Suketoshi; Charcosset, Alain; Warburton, Marilyn L

    2017-01-01

    This study describes the genetic diversity and population structure of 194 native maize populations from 23 countries of Latin America and the Caribbean. The germplasm, representing 131 distinct landraces, was genetically characterized as population bulks using 28 SSR markers. Three main groups of maize germplasm were identified. The first, the Mexico and Southern Andes group, highlights the Pre-Columbian and modern exchange of germplasm between North and South America. The second group, Mesoamerica lowland, supports the hypothesis that two separate human migration events could have contributed to Caribbean maize germplasm. The third, the Andean group, displayed early introduction of maize into the Andes, with little mixing since then, other than a regional interchange zone active in the past. Events and activities in the pre- and post-Columbian Americas including the development and expansion of pre-Columbian cultures and the arrival of Europeans to the Americas are discussed in relation to the history of maize migration from its point of domestication in Mesoamerica to South America and the Caribbean through sea and land routes.

  8. Genetic mapping shows intraspecific variation and transgressive segregation for caterpillar-induced aphid resistance in maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plants in nature have inducible defenses that sometimes lead to targeted resistance against particular herbivores, but susceptibility to others. The metabolic diversity and genetic resources available for maize (Zea mays) make this a suitable system for a mechanistic study of within- species variati...

  9. Distinct genetic architectures for male and female inflorescence traits of maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We compared the genetic architecture of thirteen maize morphological traits in a large population of recombinant inbred lines. Four traits from the male inflorescence (tassel) and three traits from the female inflorescence (ear) were measured and studied using linkage and genome-wide association ana...

  10. Overexpression of ARGOS Genes Modifies Plant Sensitivity to Ethylene, Leading to Improved Drought Tolerance in Both Arabidopsis and Maize[OPEN

    PubMed Central

    Shi, Jinrui; Habben, Jeffrey E.; Archibald, Rayeann L.; Drummond, Bruce J.; Chamberlin, Mark A.; Williams, Robert W.; Lafitte, H. Renee; Weers, Ben P.

    2015-01-01

    Lack of sufficient water is a major limiting factor to crop production worldwide, and the development of drought-tolerant germplasm is needed to improve crop productivity. The phytohormone ethylene modulates plant growth and development as well as plant response to abiotic stress. Recent research has shown that modifying ethylene biosynthesis and signaling can enhance plant drought tolerance. Here, we report novel negative regulators of ethylene signal transduction in Arabidopsis (Arabidopsis thaliana) and maize (Zea mays). These regulators are encoded by the ARGOS gene family. In Arabidopsis, overexpression of maize ARGOS1 (ZmARGOS1), ZmARGOS8, Arabidopsis ARGOS homolog ORGAN SIZE RELATED1 (AtOSR1), and AtOSR2 reduced plant sensitivity to ethylene, leading to enhanced drought tolerance. RNA profiling and genetic analysis suggested that the ZmARGOS1 transgene acts between an ethylene receptor and CONSTITUTIVE TRIPLE RESPONSE1 in the ethylene signaling pathway, affecting ethylene perception or the early stages of ethylene signaling. Overexpressed ZmARGOS1 is localized to the endoplasmic reticulum and Golgi membrane, where the ethylene receptors and the ethylene signaling protein ETHYLENE-INSENSITIVE2 and REVERSION-TO-ETHYLENE SENSITIVITY1 reside. In transgenic maize plants, overexpression of ARGOS genes also reduces ethylene sensitivity. Moreover, field testing showed that UBIQUITIN1:ZmARGOS8 maize events had a greater grain yield than nontransgenic controls under both drought stress and well-watered conditions. PMID:26220950

  11. Maize databases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter is a succinct overview of maize data held in the species-specific database MaizeGDB (the Maize Genomics and Genetics Database), and selected multi-species data repositories, such as Gramene/Ensembl Plants, Phytozome, UniProt and the National Center for Biotechnology Information (NCBI), ...

  12. Simultaneous Detection of Genetically Modified Organisms in a Mixture by Multiplex PCR-Chip Capillary Electrophoresis.

    PubMed

    Patwardhan, Supriya; Dasari, Srikanth; Bhagavatula, Krishna; Mueller, Steffen; Deepak, Saligrama Adavigowda; Ghosh, Sudip; Basak, Sanjay

    2015-01-01

    An efficient PCR-based method to trace genetically modified food and feed products is in demand due to regulatory requirements and contaminant issues in India. However, post-PCR detection with conventional methods has limited sensitivity in amplicon separation that is crucial in multiplexing. The study aimed to develop a sensitive post-PCR detection method by using PCR-chip capillary electrophoresis (PCR-CCE) to detect and identify specific genetically modified organisms in their genomic DNA mixture by targeting event-specific nucleotide sequences. Using the PCR-CCE approach, novel multiplex methods were developed to detect MON531 cotton, EH 92-527-1 potato, Bt176 maize, GT73 canola, or GA21 maize simultaneously when their genomic DNAs in mixtures were amplified using their primer mixture. The repeatability RSD (RSDr) of the peak migration time was 0.06 and 3.88% for the MON531 and Bt176, respectively. The RSD (RSDR) of the Cry1Ac peak ranged from 0.12 to 0.40% in multiplex methods. The method was sensitive in resolving amplicon of size difference up to 4 bp. The PCR-CCE method is suitable to detect multiple genetically modified events in a composite DNA sample by tagging their event specific sequences.

  13. Genetically Modified (GM) Foods and Ethical Eating.

    PubMed

    Dizon, Francis; Costa, Sarah; Rock, Cheryl; Harris, Amanda; Husk, Cierra; Mei, Jenny

    2016-02-01

    The ability to manipulate and customize the genetic code of living organisms has brought forth the production of genetically modified organisms (GMOs) and consumption of genetically modified (GM) foods. The potential for GM foods to improve the efficiency of food production, increase customer satisfaction, and provide potential health benefits has contributed to the rapid incorporation of GM foods into the American diet. However, GM foods and GMOs are also a topic of ethical debate. The use of GM foods and GM technology is surrounded by ethical concerns and situational judgment, and should ideally adhere to the ethical standards placed upon food and nutrition professionals, such as: beneficence, nonmaleficence, justice and autonomy. The future of GM foods involves many aspects and trends, including enhanced nutritional value in foods, strict labeling laws, and potential beneficial economic conditions in developing nations. This paper briefly reviews the origin and background of GM foods, while delving thoroughly into 3 areas: (1) GMO labeling, (2) ethical concerns, and (3) health and industry applications. This paper also examines the relationship between the various applications of GM foods and their corresponding ethical issues. Ethical concerns were evaluated in the context of the code of ethics developed by the Academy of Nutrition and Dietetics (AND) that govern the work of food and nutrition professionals. Overall, there is a need to stay vigilant about the many ethical implications of producing and consuming GM foods and GMOs.

  14. Systems genetics reveals a transcriptional network associated with susceptibility in the maize-grey leaf spot pathosystem

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have applied a systems genetics approach to elucidate molecular mechanisms of maize responses to gray leaf spot (GLS) disease, caused by Cercospora zeina, a major threat to maize production globally. We conducted expression QTL (eQTL) analysis of gene expression variation measured in earleaf samp...

  15. An ultra-high-density map as a community resource for discerning the genetic basis of quantitative traits in maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study, we generated a linkage map containing 1,151,856 high quality SNPs between Mo17 and B73, which were verified in the maize intermated B73'×'Mo17 (IBM) Syn10 population. This resource is an excellent complement to existing maize genetic maps available in an online database (iPlant, http:...

  16. Detection and identification of multiple genetically modified events using DNA insert fingerprinting.

    PubMed

    Raymond, Philippe; Gendron, Louis; Khalf, Moustafa; Paul, Sylvianne; Dibley, Kim L; Bhat, Somanath; Xie, Vicki R D; Partis, Lina; Moreau, Marie-Eve; Dollard, Cheryl; Coté, Marie-José; Laberge, Serge; Emslie, Kerry R

    2010-03-01

    Current screening and event-specific polymerase chain reaction (PCR) assays for the detection and identification of genetically modified organisms (GMOs) in samples of unknown composition or for the detection of non-regulated GMOs have limitations, and alternative approaches are required. A transgenic DNA fingerprinting methodology using restriction enzyme digestion, adaptor ligation, and nested PCR was developed where individual GMOs are distinguished by the characteristic fingerprint pattern of the fragments generated. The inter-laboratory reproducibility of the amplified fragment sizes using different capillary electrophoresis platforms was compared, and reproducible patterns were obtained with an average difference in fragment size of 2.4 bp. DNA insert fingerprints for 12 different maize events, including two maize hybrids and one soy event, were generated that reflected the composition of the transgenic DNA constructs. Once produced, the fingerprint profiles were added to a database which can be readily exchanged and shared between laboratories. This approach should facilitate the process of GMO identification and characterization.

  17. Fatty acid production in genetically modified cyanobacteria

    PubMed Central

    Liu, Xinyao; Sheng, Jie; Curtiss III, Roy

    2011-01-01

    To avoid costly biomass recovery in photosynthetic microbial biofuel production, we genetically modified cyanobacteria to produce and secrete fatty acids. Starting with introducing an acyl–acyl carrier protein thioesterase gene, we made six successive generations of genetic modifications of cyanobacterium Synechocystis sp. PCC6803 wild type (SD100). The fatty acid secretion yield was increased to 197 ± 14 mg/L of culture in one improved strain at a cell density of 1.0 × 109 cells/mL by adding codon-optimized thioesterase genes and weakening polar cell wall layers. Although these strains exhibited damaged cell membranes at low cell densities, they grew more rapidly at high cell densities in late exponential and stationary phase and exhibited less cell damage than cells in wild-type cultures. Our results suggest that fatty acid secreting cyanobacteria are a promising technology for renewable biofuel production. PMID:21482809

  18. Spectroscopic characterization of genetically modified flax fibers

    NASA Astrophysics Data System (ADS)

    Dymińska, L.; Gągor, A.; Hanuza, J.; Kulma, A.; Preisner, M.; Żuk, M.; Szatkowski, M.; Szopa, J.

    2014-09-01

    The principal goal of this paper is an analysis of flax fiber composition. Natural and genetically modified flax fibers derived from transgenic flax have been analyzed. Development of genetic engineering enables to improve the quality of fibers. Three transgenic plant lines with different modifications were generated based on fibrous flax plants as the origin. These are plants with: silenced cinnamyl alcohol dehydrogenase (CAD) gene; overexpression of polygalacturonase (PGI); and expression of three genes construct containing β-ketothiolase (phb A), acetoacetyl-CoA reductase (phb B), and poly-3-hydroxybutyric acid synthase (phb C). Flax fibers have been studied by FT-IR spectroscopy. The integral intensities of the IR bands have been used for estimation of the chemical content of the normal and transgenic flaxes. The spectroscopic data were compared to those obtained from chemical analysis of flax fibers. X-ray studies have been used to characterize the changes of the crystalline structure of the flax cellulose fibers.

  19. [Genetically modified organisms (GMO): toxicological aspects].

    PubMed

    Ludwicki, J K

    1998-01-01

    The genetically modified organisms (GMO) are one of the major public concerns partially due to the activity of the non-governmental organizations which believe that public opinion must be duly informed on what leaves the laboratories and enters the environment or is proposed as food. This article discusses some major toxicological and nutritional aspects of GMO designed as food for humans. The range of current use of GMOs, potential hazards for humans, safety assessment, allergenic concerns, and some aspects of the use of marker genes are discussed in regard to human safety. The need for relevant regulations is stressed.

  20. Genetically modified organisms (GMOs) and aquaculture.

    PubMed

    Beardmore, J A; Porter, Joanne S

    2003-01-01

    This paper reviews the nature of genetically modified organisms (GMOs), the range of aquatic species in which GMOs have been produced, the methods and target genes employed, the benefits to aquaculture, the problems attached to use of GMOs in aquatic species and the regulatory and other social frameworks surrounding them. A set of recommendations aimed at best practice is appended. This states the potential value of GMOs in aquaculture but also calls for improved knowledge particularly of sites of integration, risk analysis, progress in achieving sterility in fish for production and better dissemination of relevant information.

  1. Identification and genetic characterization of maize cell wall variation for improved biorefinery feedstock characteristics

    SciTech Connect

    Pauly, Markus; Hake, Sarah

    2013-10-31

    The objectives of this program are to 1) characterize novel maize mutants with altered cell walls for enhanced biorefinery characteristics and 2) find quantitative trait loci (QTLs) related to biorefinery characteristics by taking advantage of the genetic diversity of maize. As a result a novel non-transgenic maize plant (cal1) has been identified, whose stover (leaves and stalk) contain more glucan in their walls leading to a higher saccharification yield, when subjected to a standard enzymatic digestion cocktail. Stacking this trait with altered lignin mutants yielded evene higher saccharification yields. Cal-1 mutants do not show a loss of kernel and or biomass yield when grown in the field . Hence, cal1 biomass provides an excellent feedstock for the biofuel industry.

  2. Breeding maize as biogas substrate in Central Europe: I. Quantitative-genetic parameters for testcross performance.

    PubMed

    Grieder, Christoph; Dhillon, Baldev S; Schipprack, Wolfgang; Melchinger, Albrecht E

    2012-04-01

    Biofuels have gained importance recently and the use of maize biomass as substrate in biogas plants for production of methane has increased tremendously in Germany. The objectives of our research were to (1) estimate variance components and heritability for different traits relevant to biogas production in testcrosses (TCs) of maize, (2) study correlations among traits, and (3) discuss strategies to breed maize as a substrate for biogas fermenters. We evaluated 570 TCs of 285 diverse dent maize lines crossed with two flint single-cross testers in six environments. Data were recorded on agronomic and quality traits, including dry matter yield (DMY), methane fermentation yield (MFY), and methane yield (MY), the product of DMY and MFY, as the main target trait. Estimates of variance components showed general combining ability (GCA) to be the major source of variation. Estimates of heritability exceeded 0.67 for all traits and were even much greater in most instances. Methane yield was perfectly correlated with DMY but not with MFY, indicating that variation in MY is primarily determined by DMY. Further, DMY had a larger heritability and coefficient of genetic variation than MFY. Hence, for improving MY, selection should primarily focus on DMY rather than MFY. Further, maize breeding for biogas production may diverge from that for forage production because in the former case, quality traits seem to be of much lower importance.

  3. Multivariate analysis of maize disease resistances suggests a pleiotropic genetic basis and implicates a GST gene

    PubMed Central

    Wisser, Randall J.; Kolkman, Judith M.; Patzoldt, Megan E.; Holland, James B.; Yu, Jianming; Krakowsky, Matthew; Nelson, Rebecca J.; Balint-Kurti, Peter J.

    2011-01-01

    Plants are attacked by pathogens representing diverse taxonomic groups, such that genes providing multiple disease resistance (MDR) are expected to be under positive selection pressure. To address the hypothesis that naturally occurring allelic variation conditions MDR, we extended the framework of structured association mapping to allow for the analysis of correlated complex traits and the identification of pleiotropic genes. The multivariate analytical approach used here is directly applicable to any species and set of traits exhibiting correlation. From our analysis of a diverse panel of maize inbred lines, we discovered high positive genetic correlations between resistances to three globally threatening fungal diseases. The maize panel studied exhibits rapidly decaying linkage disequilibrium that generally occurs within 1 or 2 kb, which is less than the average length of a maize gene. The positive correlations therefore suggested that functional allelic variation at specific genes for MDR exists in maize. Using a multivariate test statistic, a glutathione S-transferase (GST) gene was found to be associated with modest levels of resistance to all three diseases. Resequencing analysis pinpointed the association to a histidine (basic amino acid) for aspartic acid (acidic amino acid) substitution in the encoded protein domain that defines GST substrate specificity and biochemical activity. The known functions of GSTs suggested that variability in detoxification pathways underlie natural variation in maize MDR. PMID:21490302

  4. Genetic diversity in elite inbred lines of maize and its association with heterosis.

    PubMed

    Fernandes, E H; Schuster, I; Scapim, C A; Vieira, E S N; Coan, M M D

    2015-06-12

    The objective of the current study was to apply molecular markers (microsatellites) in the analysis of genetic diversity of 48 lines of the elite maize germplasm stored in the bank of the Cooperativa Central de Pesquisa Agrícola - Coodetec, PR, Brazil, and estimate the correlation between genetic distance and heterosis and hybrid performance from the crosses among these maize lines. Forty-four random primers were used and amplification of 124 polymorphic fragments was obtained. The expected findings from the correlation of the yield and heterosis with the genetic distance were non-significant. However, the results suggested that data from the extreme distances could be used in breeding for more productive crosses and heterotic hybrids. Thereby, molecular markers are efficient tools for predicting hybrid performance.

  5. Development of an innovative immunoassay for CP4EPSPS and Cry1AB genetically modified protein detection and quantification.

    PubMed

    Ermolli, M; Prospero, A; Balla, B; Querci, M; Mazzeo, A; Van Den Eede, G

    2006-09-01

    An innovative immunoassay, called enzyme-linked immunoabsorbant assay (ELISA) Reverse, based on a new conformation of the solid phase, was developed. The solid support was expressly designed to be immersed directly in liquid samples to detect the presence of protein targets. Its application is proposed in those cases where a large number of samples have to be screened simultaneously or when the simultaneous detection of different proteins is required. As a first application, a quantitative immunoassay for Cry1AB protein in genetically modified maize was optimized. The method was tested using genetically modified organism concentrations from 0.1 to 2.0%. The limit of detection and limit of quantitation of the method were determined as 0.0056 and 0.0168 (expressed as the percentage of genetically modified organisms content), respectively. A qualitative multiplex assay to assess the presence of two genetically modified proteins simultaneously was also established for the case of the Cry1AB and the CP4EPSPS (5-enolpyruvylshikimate-3-phosphate synthase) present in genetically modified maize and soy, respectively.

  6. Societal aspects of genetically modified foods.

    PubMed

    Frewer, L; Lassen, J; Kettlitz, B; Scholderer, J; Beekman, V; Berdal, K G

    2004-07-01

    This paper aims to examine some of the reasons behind public controversy associated with the introduction of genetically modified foods in Europe the 1990s. The historical background to the controversy is provided to give context. The issue of public acceptance of genetically modified foods, and indeed the emerging biosciences more generally, is considered in the context of risk perceptions and attitudes, public trust in regulatory institutions, scientists, and industry, and the need to develop communication strategies that explicitly include public concerns rather than exclude them. Increased public participation has been promoted as a way of increasing trust in institutional practices associated with the biosciences, although questions still arise as to how to best utilise the outputs of such exercises in policy development. This issue will become more of a priority as decision-making systems become more transparent and open to public scrutiny. The results are discussed in the context of risk assessment and risk management, and recommendations for future research are made. In particular, it is recommended that new methods are developed in order to integrate public values more efficaciously into risk analysis processes, specifically with respect to the biosciences and to technology implementation in general.

  7. Reinventing MaizeGDB

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Maize Database (MaizeDB) to the Maize Genetics and Genomics Database (MaizeGDB) turns 20 this year, and such a significant milestone must be celebrated! With the release of the B73 reference sequence and more sequenced genomes on the way, the maize community needs to address various opportunitie...

  8. [Detection of recombinant-DNA in foods from stacked genetically modified plants].

    PubMed

    Sorokina, E Iu; Chernyshova, O N

    2012-01-01

    A quantitative real-time multiplex polymerase chain reaction method was applied to the detection and quantification of MON863 and MON810 in stacked genetically modified maize MON 810xMON 863. The limit of detection was approximately 0,1%. The accuracy of the quantification, measured as bias from the accepted value and the relative repeatability standard deviation, which measures the intra-laboratory variability, were within 25% at each GM-level. A method verification has demonstrated that the MON 863 and the MON810 methods can be equally applied in quantification of the respective events in stacked MON810xMON 863.

  9. Challenges in testing genetically modified crops for potential increases in endogenous allergen expression for safety.

    PubMed

    Panda, R; Ariyarathna, H; Amnuaycheewa, P; Tetteh, A; Pramod, S N; Taylor, S L; Ballmer-Weber, B K; Goodman, R E

    2013-02-01

    Premarket, genetically modified (GM) plants are assessed for potential risks of food allergy. The major risk would be transfer of a gene encoding an allergen or protein nearly identical to an allergen into a different food source, which can be assessed by specific serum testing. The potential that a newly expressed protein might become an allergen is evaluated based on resistance to digestion in pepsin and abundance in food fractions. If the modified plant is a common allergenic source (e.g. soybean), regulatory guidelines suggest testing for increases in the expression of endogenous allergens. Some regulators request evaluating endogenous allergens for rarely allergenic plants (e.g. maize and rice). Since allergic individuals must avoid foods containing their allergen (e.g. peanut, soybean, maize, or rice), the relevance of the tests is unclear. Furthermore, no acceptance criteria are established and little is known about the natural variation in allergen concentrations in these crops. Our results demonstrate a 15-fold difference in the major maize allergen, lipid transfer protein between nine varieties, and complex variation in IgE binding to various soybean varieties. We question the value of evaluating endogenous allergens in GM plants unless the intent of the modification was production of a hypoallergenic crop.

  10. MATERNAL EFFECTS IN ADVANCED HYBRIDS OF GENETICALLY MODIFIED AND NON-GENETICALLY MODIFIED BRASSICA SPECIES

    EPA Science Inventory

    Identification of fitness traits potentially impacted by gene flow from genetically modified (GM) crops to compatible relatives is of interest in risk assessments for GM crops. Reciprocal crosses were made between GM canola, Brassica napus cv. RaideRR that expresses CP4 EPSPS fo...

  11. Rapid amplification of genetically modified organisms using a circular ferrofluid-driven PCR microchip.

    PubMed

    Sun, Yi; Kwok, Yien-Chian; Foo-Peng Lee, Peter; Nguyen, Nam-Trung

    2009-07-01

    The use of genetically modified organisms (GMOs) as food and in food products is becoming more and more widespread. Polymerase chain reaction (PCR) technology is extensively used for the detection of GMOs in food products in order to verify compliance with labeling requirements. In this paper, we present a novel close-loop ferrofluid-driven PCR microchip for rapid amplification of GMOs. The microchip was fabricated in polymethyl methacrylate by CO2 laser ablation and was integrated with three temperature zones. PCR solution was contained in a circular closed microchannel and was driven by magnetic force generated by an external magnet through a small oil-based ferrofluid plug. Successful amplification of genetically modified soya and maize were achieved in less than 13 min. This PCR microchip combines advantages of cycling flexibility and quick temperature transitions associated with two existing microchip PCR techniques, and it provides a cost saving and less time-consuming way to conduct preliminary screening of GMOs.

  12. Expanding the genetic map of maize with the intermated B73 x Mo17 (IBM) population.

    PubMed

    Lee, Michael; Sharopova, Natalya; Beavis, William D; Grant, David; Katt, Maria; Blair, Deborah; Hallauer, Arnel

    2002-01-01

    The effects of intermating on recombination and the development of linkage maps were assessed in maize. Progeny derived from a common population (B73 x Mo17) before and after five generations of intermating were genotyped at the same set of 190 RFLP loci. Intermating resulted in nearly a four-fold increase in the genetic map distance and increased the potential for improved genetic resolution in 91% of the intervals evaluated. This mapping population and related information should connect research involving dense genetic maps, physical mapping, gene isolation, comparative genomics, analysis of quantitative trait loci and investigations of heterosis.

  13. Genetic diversity of maize kernel starch-synthesis genes with SNAPs.

    PubMed

    Shin, Ji-Hyun; Kwon, Soon-Jae; Lee, Ju Kyong; Min, Hwang-Kee; Kim, Nam-Soo

    2006-10-01

    Measuring genetic diversity in populations of a crop species is very important for understanding the genetic structure of and subsequently improving the crop species by genetic manipulation. Single-nucleotide amplified polymorphisms (SNAPs) among and within maize populations of waxy, dent, and sweet corns at 25 single-nucleotide polymorphism (SNP) sites in 6 kernel starch-synthesis genes (sh2, bt2, su1, ae1, wx1, and sh1) were determined. Because of the intensive selection of some favorable alleles in starch-synthesis genes during the breeding process, and the resultant strong linkage disequilibrium (LD), the number of haplotypes in each population was far less than expected. Subsequent phenetic clustering analysis with the SNAPs indicated that the dent, waxy, and sweet corns formed distinct subclusters, except in a few incidences. LD was surveyed among SNAPs of intragenic, intergenic, and intrachromosomal SNPs in whole and subpopulations, which revealed that some SNAPs showed high LD with many other SNAPs, but some SNAPs showed low or no significant LD with others, depending on the subpopulation, indicating that these starch genes have undergone different selection in each subpopulation during the breeding process. Because the starch synthesis genes used in this study are important in maize breeding, the genetic diversity, LD, and accessions having rare SNAP alleles might be valuable in maize improvement programs.

  14. Genetic Architecture of Ear Fasciation in Maize (Zea mays) under QTL Scrutiny

    PubMed Central

    Mendes-Moreira, Pedro; Alves, Mara L.; Satovic, Zlatko; dos Santos, João Pacheco; Santos, João Nina; Souza, João Cândido; Pêgo, Silas E.; Hallauer, Arnel R.; Vaz Patto, Maria Carlota

    2015-01-01

    Maize ear fasciation Knowledge of the genes affecting maize ear inflorescence may lead to better grain yield modeling. Maize ear fasciation, defined as abnormal flattened ears with high kernel row number, is a quantitative trait widely present in Portuguese maize landraces. Material and Methods Using a segregating population derived from an ear fasciation contrasting cross (consisting of 149 F2:3 families) we established a two location field trial using a complete randomized block design. Correlations and heritabilities for several ear fasciation-related traits and yield were determined. Quantitative Trait Loci (QTL) involved in the inheritance of those traits were identified and candidate genes for these QTL proposed. Results and Discussion Ear fasciation broad-sense heritability was 0.73. Highly significant correlations were found between ear fasciation and some ear and cob diameters and row number traits. For the 23 yield and ear fasciation-related traits, 65 QTL were identified, out of which 11 were detected in both environments, while for the three principal components, five to six QTL were detected per environment. Detected QTL were distributed across 17 genomic regions and explained individually, 8.7% to 22.4% of the individual traits or principal components phenotypic variance. Several candidate genes for these QTL regions were proposed, such as bearded-ear1, branched silkless1, compact plant1, ramosa2, ramosa3, tasselseed4 and terminal ear1. However, many QTL mapped to regions without known candidate genes, indicating potential chromosomal regions not yet targeted for maize ear traits selection. Conclusions Portuguese maize germplasm represents a valuable source of genes or allelic variants for yield improvement and elucidation of the genetic basis of ear fasciation traits. Future studies should focus on fine mapping of the identified genomic regions with the aim of map-based cloning. PMID:25923975

  15. Promise and issues of genetically modified crops.

    PubMed

    Chen, Hao; Lin, Yongjun

    2013-05-01

    The growing area of genetically modified (GM) crops has substantially expanded since they were first commercialized in 1996. Correspondingly, the adoption of GM crops has brought huge economic and environmental benefits. All these achievements have been primarily supported by two simple traits of herbicide tolerance and insect resistance in the past 17 years. However, this situation will change soon. Recently, the advance of new products, technologies and safety assessment approaches has provided new opportunities for development of GM crops. In this review, we focus on the developmental trend in various aspects of GM crops including new products, technical innovation and risk assessment approaches, as well as potential challenges that GM crops are currently encountering.

  16. [Genetic potentiality of utilizing Yugoslavia maize inbred lines to improve Chinese elite hybrids].

    PubMed

    Li, Yu-Ling; Wang, Chang

    2005-07-01

    In this study, 107 crosses were made using 9 Yugoslavia maize inbred line as female and 13 parent lines of 8 Chinese elite hybrids, belonging to different heterotic groups, as male. Though Dudley's method the genetic potentiality of 9 Yugoslavia maize inbred lines were analyzed for the improvement in the yield of 8 Chinese elite hybrids and main ear -kernel characters, and for their proper applications. The results showed that the introduced Yugoslavia inbreds had broad genetic basis and high breeding value in indirect utilization. Almost all Yugoslavia inbreds, including 9801, 9802, 9803, 9805, 9807, 9808, and 9809, could improve the yield of Yuyu15, GailiangYuyu20, Yuyu22, Yuyu23, Yuyu24, Shendn10 and Nongda 108 through different parents and ear-kernel characters, while the real improving effects should be proved in further practical breeding.

  17. Chinese newspaper coverage of genetically modified organisms

    PubMed Central

    2012-01-01

    Background Debates persist around the world over the development and use of genetically modified organisms (GMO). News media has been shown to both reflect and influence public perceptions of health and science related debates, as well as policy development. To better understand the news coverage of GMOs in China, we analyzed the content of articles in two Chinese newspapers that relate to the development and promotion of genetically modified technologies and GMOs. Methods Searching in the Chinese National Knowledge Infrastructure Core Newspaper Database (CNKI-CND), we collected 77 articles, including news reports, comments and notes, published between January 2002 and August 2011 in two of the major Chinese newspapers: People’s Daily and Guangming Daily. We examined articles for perspectives that were discussed and/or mentioned regarding GMOs, the risks and benefits of GMOs, and the tone of news articles. Results The newspaper articles reported on 29 different kinds of GMOs. Compared with the possible risks, the benefits of GMOs were much more frequently discussed in the articles. 48.1% of articles were largely supportive of the GM technology research and development programs and the adoption of GM cottons, while 51.9% of articles were neutral on the subject of GMOs. Risks associated with GMOs were mentioned in the newspaper articles, but none of the articles expressed negative tones in regards to GMOs. Conclusion This study demonstrates that the Chinese print media is largely supportive of GMOs. It also indicates that the print media describes the Chinese government as actively pursuing national GMO research and development programs and the promotion of GM cotton usage. So far, discussion of the risks associated with GMOs is minimal in the news reports. The media, scientists, and the government should work together to ensure that science communication is accurate and balanced. PMID:22551150

  18. Will genetically modified foods be allergenic?

    PubMed

    Taylor, S L; Hefle, S L

    2001-05-01

    Foods produced through agricultural biotechnology, including such staples as corn, soybeans, canola, and potatoes, are already reaching the consumer marketplace. Agricultural biotechnology offers the promise to produce crops with improved agronomic characteristics (eg, insect resistance, herbicide tolerance, disease resistance, and climatic tolerance) and enhanced consumer benefits (eg, better taste and texture, longer shelf life, and more nutritious). Certainly, the products of agricultural biotechnology should be subjected to a careful and complete safety assessment before commercialization. Because the genetic modification ultimately results in the introduction of new proteins into the food plant, the safety, including the potential allergenicity, of the newly introduced proteins must be assessed. Although most allergens are proteins, only a few of the many proteins found in foods are allergenic under the typical circumstances of exposure. The potential allergenicity of the introduced proteins can be evaluated by focusing on the source of the gene, the sequence homology of the newly introduced protein to known allergens, the expression level of the novel protein in the modified crop, the functional classification of the novel protein, the reactivity of the novel protein with IgE from the serum of individuals with known allergies to the source of the transferred genetic material, and various physicochemical properties of the newly introduced protein, such as heat stability and digestive stability. Few products of agricultural biotechnology (and none of the current products) will involve the transfer of genes from known allergenic sources. Applying such criteria provides reasonable assurance that the newly introduced protein has limited capability to become an allergen.

  19. Quantitative genetic analysis of chlorophyll a fluorescence parameters in maize in the field environments.

    PubMed

    Šimić, Domagoj; Lepeduš, Hrvoje; Jurković, Vlatka; Antunović, Jasenka; Cesar, Vera

    2014-07-01

    Chlorophyll fluorescence transient from initial to maximum fluorescence ("P" step) throughout two intermediate steps ("J" and "I") (JIP-test) is considered a reliable early quantitative indicator of stress in plants. The JIP-test is particularly useful for crop plants when applied in variable field environments. The aim of the present study was to conduct a quantitative trait loci (QTL) analysis for nine JIP-test parameters in maize during flowering in four field environments differing in weather conditions. QTL analysis and identification of putative candidate genes might help to explain the genetic relationship between photosynthesis and different field scenarios in maize plants. The JIP-test parameters were analyzed in the intermated B73 × Mo17 (IBM) maize population of 205 recombinant inbred lines. A set of 2,178 molecular markers across the whole maize genome was used for QTL analysis revealing 10 significant QTLs for seven JIP-test parameters, of which five were co-localized when combined over the four environments indicating polygenic inheritance and pleiotropy. Our results demonstrate that QTL analysis of chlorophyll fluorescence parameters was capable of detecting one pleiotropic locus on chromosome 7, coinciding with the gene gst23 that may be associated with efficient photosynthesis under different field scenarios.

  20. Genetic Diversity and Molecular Evolution of a Violaxanthin De-epoxidase Gene in Maize

    PubMed Central

    Xu, Jing; Li, Zhigang; Yang, Haorui; Yang, Xiaohong; Chen, Cuixia; Li, Hui

    2016-01-01

    Violaxanthin de-epoxidase (VDE) has a critical role in the carotenoid biosynthesis pathway, which is involved in protecting the photosynthesis apparatus from damage caused by excessive light. Here, a VDE gene in maize, ZmVDE1, was cloned and shown to have functional domains in common with the gramineous VDE protein. Candidate gene association analysis indicated that no polymorphic sites in ZmVDE1 were significant association with any of the examined carotenoid-related traits at P = 0.05 in an association panel containing 155 maize inbred lines. Nucleotide diversity analysis of VDE1 in maize and teosinte indicated that its exon had less genetic variation, consistent with the conserved function of VDE1 in plants. In addition, dramatically reduced nucleotide diversity, fewer haplotypes and a significantly negative parameter deviation for Tajima’s D test of ZmVDE1 in maize and teosinte suggested that a potential selective force had acted across the ZmVDE1 locus. We further identified a 4.2 Mb selective sweep with low recombination surrounding the ZmVDE1 locus that resulted in severely reduced nucleotide diversity on chromosome 2. Collectively, natural selection and the conserved domains of ZmVDE1 might show an important role in the xanthophyll cycle of the carotenoid biosynthesis pathway. PMID:27507987

  1. The maize milkweed pod1 mutant reveals a mechanism to modify organ morphology.

    PubMed

    Johnston, Robyn; Candela, Héctor; Hake, Sarah; Foster, Toshi

    2010-07-01

    Plant lateral organs, such as leaves, have three primary axes of growth-proximal-distal, medial--lateral and adaxial-abaxial (dorsal-ventral). Although most leaves are planar, modified leaf forms, such as the bikeeled grass prophyll, can be found in nature. A detailed examination of normal prophyll development indicates that polarity is established differently in the keels than in other parts of the prophyll. Analysis of the maize HD-ZIPIII gene rolled leaf1 (rld1) suggests that altered expression patterns are responsible for keel outgrowth. Recessive mutations in the maize (Zea mays) KANADI (KAN) gene milkweed pod1 (mwp1), which promotes abaxial cell identity, strongly affect development of the prophyll and silks (fused carpels). The prophyll is reduced to two unfused midribs and the silks are narrow and misshapen. Our data indicate that the prophyll and other fused organs are particularly sensitive to disruptions in adaxial-abaxial polarity. In addition, lateral and proximal-distal growth of most lateral organs is reduced in the mwp1-R mutant, supporting a role for the adaxial-abaxial boundary in promoting growth along both axes. We propose that the adaxial-abaxial patterning mechanism has been co-opted during evolution to generate diverse organ morphologies.

  2. Production of resistant starch by extrusion cooking of acid-modified normal-maize starch.

    PubMed

    Hasjim, Jovin; Jane, Jay-Lin

    2009-09-01

    The objective of this study was to utilize extrusion cooking and hydrothermal treatment to produce resistant starch (RS) as an economical alternative to a batch-cooking process. A hydrothermal treatment (110 degrees C, 3 d) of batch-cooked and extruded starch samples facilitated propagation of heat-stable starch crystallites and increased the RS contents from 2.1% to 7.7% up to 17.4% determined using AOAC Method 991.43 for total dietary fiber. When starch samples were batch cooked and hydrothermally treated at a moisture content below 70%, acid-modified normal-maize starch (AMMS) produced a greater RS content than did native normal-maize starch (NMS). This was attributed to the partially hydrolyzed, smaller molecules in the AMMS, which had greater mobility and freedom than the larger molecules in the NMS. The RS contents of the batch-cooked and extruded AMMS products after the hydrothermal treatment were similar. A freezing treatment of the AMMS samples at -20 degrees C prior to the hydrothermal treatment did not increase the RS content. The DSC thermograms and the X-ray diffractograms showed that retrograded amylose and crystalline starch-lipid complex, which had melting temperatures above 100 degrees C, accounted for the RS contents.

  3. Model studies on the detectability of genetically modified feeds in milk.

    PubMed

    Poms, R E; Hochsteiner, W; Luger, K; Glössl, J; Foissy, H

    2003-02-01

    Detecting the use of genetically modified feeds in milk has become important, because the voluntary labeling of milk and dairy products as "GMO free" or as "organically grown" prohibits the employment of genetically modified organisms (GMOs). The aim of this work was to investigate whether a DNA transfer from foodstuffs like soya and maize was analytically detectable in cow's milk after digestion and transportation via the bloodstream of dairy cows and, thus, whether milk could report for the employment of transgene feeds. Blood, milk, urine, and feces of dairy cows were examined, and foreign DNA was detected by polymerase chain reaction by specifically amplifying a 226-bp fragment of the maize invertase gene and a 118-bp fragment of the soya lectin gene. An intravenous application of purified plant DNA showed a fast elimination of marker DNA in blood or its reduction below the detection limit. With feeding experiments, it could be demonstrated that a specific DNA transfer from feeds into milk was not detectable. Therefore, foreign DNA in milk cannot serve as an indicator for the employment of transgene feeds unless milk is directly contaminated with feed components or airborne feed particles.

  4. Genetic control of the number of leaves above the ear in maize.

    PubMed

    Freire, A I; Dias, K O G; Oliveira, L B V; Nalin, R S; Guedes, F L; Souza, J C

    2015-02-13

    In this study, we examined the genetic control of the number of leaves above the first ear in maize. The F₂ generations and the backcrosses were obtained from 2 contrasting lines for this trait. All generations were assessed in a completely randomized block design with 2 replications. The number of leaves above the ear was counted when the plants were in the tasseling stage at the level of plants per plot. Mean and variance components were estimated using the weighted least square method. We observed a predominance of non-additive effects in the genetic control of number of leaves above the ear. These results indicate that this trait shows high heritability.

  5. Genetic studies on cytoplasmic male sterility in maize

    SciTech Connect

    Laughnan, J.R.

    1992-01-01

    Our research concerns the basic mechanisms of cytoplasmic male sterility (CMS) and fertility restoration in maize. The molecular determination of CMS is in the DNA of the mitochondria (mtDNA) but specific nuclear restorer-of-fertility (Rf) genes can overrule the male-sterile effect of the cytoplasm. Our approach to the study of the Rf genes is threefold. We are attempting to tag the cms-S Rf genes and the cms-T Rf2 gene with controlling elements (CEs). Since we have identified a number of spontaneous Rf genes for cms-S and have demonstrated that they are themselves transposable, we are also searching for cases in which an Rf gene is inserted into a wild-type gene. The other aspect of our research involves the nuclear control over the organization of the mitochondrial genome. We found that the changes in mtDNA organization upon cytoplasmic reversion to fertility were characteristic of the nuclear background in which the reversion event occurred. We have investigated whether these differences are a reflection of differences in the organization of the mtDNA genome before reversion.

  6. Production of certified reference materials for the detection of genetically modified organisms.

    PubMed

    Trapmann, Stefanie; Schimmel, Heinz; Kramer, Gerard Nico; Van den Eede, Guy; Pauwels, Jean

    2002-01-01

    Certified reference materials (CRMs) are an essenIial tool in the quality assurance of analytical measurements. They are produced, certified, and used in accordance with relevant ISO (International Organization for Standardization) and BCR (Community Bureau of Reference) guidelines. The Institute for Reference Materials and Measurements (IRMM; Geel, Belgium) has produced the first powdery genetically modified organism (GMO) CRMs in cooperation with the Institute for Health and Consumer Protection (Ispra, Italy). Until now, different weight percentages in the range of 0-5% for 4 GMOs in Europe were produced and certified: Bt (Bacillus thuringiensis)-11 and Bt-176 maize, Roundup Ready soybean, and MON810 maize. Bt-11 and Bt-176 maize and Roundup Ready soybean were produced by IRMM on behalf of Fluka Chemie AG (Buchs, Switzerland). Characterization of used base material is the first step in production and is especially important for GMO CRMs. The production of powdery GMO CRMs and methods used for production control are described. Thorough control of homogeneity and stability are essential for certification of reference materials and ensure validity of the certificate for each bottle of a batch throughout a defined shelf-life. Because production of reference materials and their maintenance are very labor- and cost-intensive tasks, the usefulness of new types of GMO CRMs must be estimated carefully.

  7. Genetic Analysis of Kernel Traits in Maize-Teosinte Introgression Populations.

    PubMed

    Liu, Zhengbin; Garcia, Arturo; McMullen, Michael D; Flint-Garcia, Sherry A

    2016-08-09

    Seed traits have been targeted by human selection during the domestication of crop species as a way to increase the caloric and nutritional content of food during the transition from hunter-gather to early farming societies. The primary seed trait under selection was likely seed size/weight as it is most directly related to overall grain yield. Additional seed traits involved in seed shape may have also contributed to larger grain. Maize (Zea mays ssp. mays) kernel weight has increased more than 10-fold in the 9000 years since domestication from its wild ancestor, teosinte (Z. mays ssp. parviglumis). In order to study how size and shape affect kernel weight, we analyzed kernel morphometric traits in a set of 10 maize-teosinte introgression populations using digital imaging software. We identified quantitative trait loci (QTL) for kernel area and length with moderate allelic effects that colocalize with kernel weight QTL. Several genomic regions with strong effects during maize domestication were detected, and a genetic framework for kernel traits was characterized by complex pleiotropic interactions. Our results both confirm prior reports of kernel domestication loci and identify previously uncharacterized QTL with a range of allelic effects, enabling future research into the genetic basis of these traits.

  8. Genetic Analysis of Kernel Traits in Maize-Teosinte Introgression Populations

    PubMed Central

    Liu, Zhengbin; Garcia, Arturo; McMullen, Michael D.; Flint-Garcia, Sherry A.

    2016-01-01

    Seed traits have been targeted by human selection during the domestication of crop species as a way to increase the caloric and nutritional content of food during the transition from hunter-gather to early farming societies. The primary seed trait under selection was likely seed size/weight as it is most directly related to overall grain yield. Additional seed traits involved in seed shape may have also contributed to larger grain. Maize (Zea mays ssp. mays) kernel weight has increased more than 10-fold in the 9000 years since domestication from its wild ancestor, teosinte (Z. mays ssp. parviglumis). In order to study how size and shape affect kernel weight, we analyzed kernel morphometric traits in a set of 10 maize-teosinte introgression populations using digital imaging software. We identified quantitative trait loci (QTL) for kernel area and length with moderate allelic effects that colocalize with kernel weight QTL. Several genomic regions with strong effects during maize domestication were detected, and a genetic framework for kernel traits was characterized by complex pleiotropic interactions. Our results both confirm prior reports of kernel domestication loci and identify previously uncharacterized QTL with a range of allelic effects, enabling future research into the genetic basis of these traits. PMID:27317774

  9. Genetically modified organisms and visceral leishmaniasis.

    PubMed

    Chhajer, Rudra; Ali, Nahid

    2014-01-01

    Vaccination is the most effective method of preventing infectious diseases. Since the eradication of small pox in 1976, many other potentially life compromising if not threatening diseases have been dealt with subsequently. This event was a major leap not only in the scientific world already burdened with many diseases but also in the mindset of the common man who became more receptive to novel treatment options. Among the many protozoan diseases, the leishmaniases have emerged as one of the largest parasite killers of the world, second only to malaria. There are three types of leishmaniasis namely cutaneous (CL), mucocutaneous (ML), and visceral (VL), caused by a group of more than 20 species of Leishmania parasites. Visceral leishmaniasis, also known as kala-azar is the most severe form and almost fatal if untreated. Since the first attempts at leishmanization, we have killed parasite vaccines, subunit protein, or DNA vaccines, and now we have live recombinant carrier vaccines and live attenuated parasite vaccines under various stages of development. Although some research has shown promising results, many more potential genes need to be evaluated as live attenuated vaccine candidates. This mini-review attempts to summarize the success and failures of genetically modified organisms used in vaccination against some of major parasitic diseases for their application in leishmaniasis.

  10. Genetically modified crops and food security.

    PubMed

    Qaim, Matin; Kouser, Shahzad

    2013-01-01

    The role of genetically modified (GM) crops for food security is the subject of public controversy. GM crops could contribute to food production increases and higher food availability. There may also be impacts on food quality and nutrient composition. Finally, growing GM crops may influence farmers' income and thus their economic access to food. Smallholder farmers make up a large proportion of the undernourished people worldwide. Our study focuses on this latter aspect and provides the first ex post analysis of food security impacts of GM crops at the micro level. We use comprehensive panel data collected over several years from farm households in India, where insect-resistant GM cotton has been widely adopted. Controlling for other factors, the adoption of GM cotton has significantly improved calorie consumption and dietary quality, resulting from increased family incomes. This technology has reduced food insecurity by 15-20% among cotton-producing households. GM crops alone will not solve the hunger problem, but they can be an important component in a broader food security strategy.

  11. Health risks of genetically modified foods.

    PubMed

    Dona, Artemis; Arvanitoyannis, Ioannis S

    2009-02-01

    As genetically modified (GM) foods are starting to intrude in our diet concerns have been expressed regarding GM food safety. These concerns as well as the limitations of the procedures followed in the evaluation of their safety are presented. Animal toxicity studies with certain GM foods have shown that they may toxically affect several organs and systems. The review of these studies should not be conducted separately for each GM food, but according to the effects exerted on certain organs it may help us create a better picture of the possible health effects on human beings. The results of most studies with GM foods indicate that they may cause some common toxic effects such as hepatic, pancreatic, renal, or reproductive effects and may alter the hematological, biochemical, and immunologic parameters. However, many years of research with animals and clinical trials are required for this assessment. The use of recombinant GH or its expression in animals should be re-examined since it has been shown that it increases IGF-1 which may promote cancer.

  12. Genetically modified plants and human health

    PubMed Central

    Key, Suzie; Ma, Julian K-C; Drake, Pascal MW

    2008-01-01

    Summary Genetically modified (or GM) plants have attracted a large amount of media attention in recent years and continue to do so. Despite this, the general public remains largely unaware of what a GM plant actually is or what advantages and disadvantages the technology has to offer, particularly with regard to the range of applications for which they can be used. From the first generation of GM crops, two main areas of concern have emerged, namely risk to the environment and risk to human health. As GM plants are gradually being introduced into the European Union there is likely to be increasing public concern regarding potential health issues. Although it is now commonplace for the press to adopt ‘health campaigns’, the information they publish is often unreliable and unrepresentative of the available scientific evidence. We consider it important that the medical profession should be aware of the state of the art, and, as they are often the first port of call for a concerned patient, be in a position to provide an informed opinion. This review will examine how GM plants may impact on human health both directly – through applications targeted at nutrition and enhancement of recombinant medicine production – but also indirectly, through potential effects on the environment. Finally, it will examine the most important opposition currently facing the worldwide adoption of this technology: public opinion. PMID:18515776

  13. Independent genetic control of maize (Zea mays L.) kernel weight determination and its phenotypic plasticity.

    PubMed

    Alvarez Prado, Santiago; Sadras, Víctor O; Borrás, Lucas

    2014-08-01

    Maize kernel weight (KW) is associated with the duration of the grain-filling period (GFD) and the rate of kernel biomass accumulation (KGR). It is also related to the dynamics of water and hence is physiologically linked to the maximum kernel water content (MWC), kernel desiccation rate (KDR), and moisture concentration at physiological maturity (MCPM). This work proposed that principles of phenotypic plasticity can help to consolidated the understanding of the environmental modulation and genetic control of these traits. For that purpose, a maize population of 245 recombinant inbred lines (RILs) was grown under different environmental conditions. Trait plasticity was calculated as the ratio of the variance of each RIL to the overall phenotypic variance of the population of RILs. This work found a hierarchy of plasticities: KDR ≈ GFD > MCPM > KGR > KW > MWC. There was no phenotypic and genetic correlation between traits per se and trait plasticities. MWC, the trait with the lowest plasticity, was the exception because common quantitative trait loci were found for the trait and its plasticity. Independent genetic control of a trait per se and genetic control of its plasticity is a condition for the independent evolution of traits and their plasticities. This allows breeders potentially to select for high or low plasticity in combination with high or low values of economically relevant traits.

  14. Genetically modified crops: Brazilian law and overview.

    PubMed

    Marinho, C D; Martins, F J O; Amaral Júnior, A T; Gonçalves, L S A; dos Santos, O J A P; Alves, D P; Brasileiro, B P; Peternelli, L A

    2014-07-07

    In Brazil, the first genetically modified (GM) crop was released in 1998, and it is estimated that 84, 78, and 50% of crop areas containing soybean, corn, and cotton, respectively, were transgenic in 2012. This intense and rapid adoption rate confirms that the choice to use technology has been the main factor in developing national agriculture. Thus, this review focuses on understanding these dynamics in the context of farmers, trade relations, and legislation. To accomplish this goal, a survey was conducted using the database of the National Cultivar Registry and the National Service for Plant Variety Protection of the Ministry of Agriculture, Livestock and Supply [Ministério da Agricultura, Pecuária e Abastecimento (MAPA)] between 1998 and October 13, 2013. To date, 36 events have been released: five for soybeans, 18 for corn, 12 for cotton, and one for beans. From these events, 1395 cultivars have been developed and registered: 582 for soybean, 783 for corn and 30 for cotton. Monsanto owns 73.05% of the technologies used to develop these cultivars, while the Dow AgroScience - DuPont partnership and Syngenta have 16.34 and 4.37% ownership, respectively. Thus, the provision of transgenic seeds by these companies is an oligopoly supported by legislation. Moreover, there has been a rapid replacement of conventional crops by GM crops, whose technologies belong almost exclusively to four multinational companies, with the major ownership by Monsanto. These results reflect a warning to the government of the increased dependence on multinational corporations for key agricultural commodities.

  15. Glucose and sucrose differentially modify cell proliferation in maize during germination.

    PubMed

    Lara-Núñez, Aurora; García-Ayala, Brendy B; Garza-Aguilar, Sara M; Flores-Sánchez, Jesús; Sánchez-Camargo, Victor A; Bravo-Alberto, Carlos E; Vázquez-Santana, Sonia; Vázquez-Ramos, Jorge M

    2017-04-01

    Glucose and sucrose play a dual role: as carbon and energy sources and as signaling molecules. In order to address the impact that sugars may have on maize seeds during germination, embryo axes were incubated with or without either of the two sugars. Expression of key cell cycle markers and protein abundance, cell patterning and de novo DNA synthesis in root meristem zones were analyzed. Embryo axes without added sugars in imbibition medium were unable to grow after 7 days; in sucrose, embryo axes developed seminal and primary roots with numerous root hairs, whereas in glucose axes showed a twisted morphology, no root hair formation but callus-like structures on adventitious and primary seminal roots. More and smaller cells were observed with glucose treatment in root apical meristems. de novo DNA synthesis was stimulated more by glucose than by sucrose. At 24 h of imbibition, expression of ZmCycD2;2a and ZmCycD4;2 was increased by sucrose and reduced by glucose. CDKA1;1 and CDKA2;1 expression was stimulated equally by both sugars. Protein abundance patterns were modified by sugars: ZmCycD2 showed peaks on glucose at 12 and 36 h of imbibition whereas sucrose promoted ZmCycD3 protein accumulation. In presence of glucose ZmCycD3, ZmCycD4 and ZmCycD6 protein abundance was reduced after 24 h. Finally, both sugars stimulated ZmCDKA protein accumulation but at different times. Overall, even though glucose appears to act as a stronger mitogen stimulator, sucrose stimulated the expression of more cell cycle markers during germination. This work provides evidence of a differential response of cell cycle markers to sucrose and glucose during maize germination that may affect the developmental program during plantlet establishment.

  16. Use of Genetic Effects and Genotype by Environmental Interactions for the Classification of Mexican Races of Maize

    PubMed Central

    Cervantes, Tarcicio S.; Goodman, Major M.; Casas, Eduardo D.; Rawlings, John O.

    1978-01-01

    To examine the questions of whether the additive and dominance effects present for morphological characters in racial crosses are of sufficient consistency and magnitude to allow such genetic effects to be used for racial classification, we used a diallel experiment among the 25 well-defined Mexican races of maize, which include the ancestral stocks of most commercial and genetic maize types. With such an experiment, genetic effects and genotype by environmental interactions for one or more characters can be used to measure genetic and adaptational or environmental similarity. We used average parental effects (general combining abilities), specific effects, and genotype by environmental effects of 21 characters from the diallel (grown at three locations) to group the Mexican races of maize. The groupings based upon average genetic effects and upon genotype by environmental interactions are more satisfactory than groupings based upon specific effects. The standard errors for genetic distances based upon specific (largely dominance) effects seem to be too high for practical use. Principal components analyses of the same data suggest a similar conclusion.—The groupings based upon average genetic effects are in general agreement with previous studies, with the exception of Maíz Dulce, which is grouped with the Cónicos, rather than being isolated from the other Mexican races of maize. PMID:17248866

  17. Morphological and genetic characterization of endophytic bacteria isolated from roots of different maize genotypes.

    PubMed

    Ikeda, Angela Cristina; Bassani, Luciana Lange; Adamoski, Douglas; Stringari, Danyelle; Cordeiro, Vanessa Kava; Glienke, Chirlei; Steffens, Maria Berenice Reynaud; Hungria, Mariangela; Galli-Terasawa, Lygia Vitoria

    2013-01-01

    Maize is one of the most important crops worldwide, and in Brazil, the state of Paraná stands as its largest producer. The crop demands high inputs of N fertilizers, therefore all strategies aiming to optimize the grain production with lower inputs are very relevant. Endophytic bacteria have a high potential to increment maize grain yield by means of input via biological nitrogen fixation and/or plant growth promotion, in this last case increasing the absorption of water and nutrients by the plants. In this study, we established a collection of 217 endophytic bacteria, isolated from roots of four lineages and three hybrid genotypes of maize, and isolated in four different N-free culture media. Biochemical-comprising growth in different carbon sources, intrinsic tolerance to antibiotics, and biochemical tests for catalase, nitrate reductase, urease, and growth in N-free media in vitro-and genetic characterization by BOX-PCR revealed great variability among the isolates. Both commercial hybrids and homozygous lineages were broadly colonized by endophytes, and sequencing of the 16S rRNA gene revealed the presence of bacteria belonging to the genera Pantoea, Bacillus, Burkholderia, and Klebsiella. Qualitative differences in endophytic colonization were detected between lineages and hybrid genotypes.

  18. Potential adverse health effects of genetically modified crops.

    PubMed

    Bakshi, Anita

    2003-01-01

    Genetically modified crops have the potential to eliminate hunger and starvation in millions of people, especially in developing countries because the genetic modification can produce large amounts of foods that are more nutritious. Large quantities are produced because genetically modified crops are more resistant to pests and drought. They also contain greater amounts of nutrients, such as proteins and vitamins. However, there are concerns about the safety of genetically modified crops. The concerns are that they may contain allergenic substances due to introduction of new genes into crops. Another concern is that genetic engineering often involves the use of antibiotic-resistance genes as "selectable markers" and this could lead to production of antibiotic-resistant bacterial strains that are resistant to available antibiotics. This would create a serious public health problem. The genetically modified crops might contain other toxic substances (such as enhanced amounts of heavy metals) and the crops might not be "substantially equivalent" in genome, proteome, and metabolome compared with unmodified crops. Another concern is that genetically modified crops may be less nutritious; for example, they might contain lower amounts of phytoestrogens, which protect against heart disease and cancer. The review of available literature indicates that the genetically modified crops available in the market that are intended for human consumption are generally safe; their consumption is not associated with serious health problems. However, because of potential for exposure of a large segment of human population to genetically modified foods, more research is needed to ensure that the genetically modified foods are safe for human consumption.

  19. High-Throughput Phenotyping and QTL Mapping Reveals the Genetic Architecture of Maize Plant Growth1[OPEN

    PubMed Central

    Huang, Chenglong; Wu, Di; Qiao, Feng; Li, Wenqiang; Duan, Lingfeng; Wang, Ke; Xiao, Yingjie; Chen, Guoxing; Liu, Qian; Yang, Wanneng

    2017-01-01

    With increasing demand for novel traits in crop breeding, the plant research community faces the challenge of quantitatively analyzing the structure and function of large numbers of plants. A clear goal of high-throughput phenotyping is to bridge the gap between genomics and phenomics. In this study, we quantified 106 traits from a maize (Zea mays) recombinant inbred line population (n = 167) across 16 developmental stages using the automatic phenotyping platform. Quantitative trait locus (QTL) mapping with a high-density genetic linkage map, including 2,496 recombinant bins, was used to uncover the genetic basis of these complex agronomic traits, and 988 QTLs have been identified for all investigated traits, including three QTL hotspots. Biomass accumulation and final yield were predicted using a combination of dissected traits in the early growth stage. These results reveal the dynamic genetic architecture of maize plant growth and enhance ideotype-based maize breeding and prediction. PMID:28153923

  20. Assessment of genetic diversity in quality protein maize(QPM) inbreds using ISSR markers.

    PubMed

    Lenka, Devraj; Tripathy, Swapan K; Kumar, Ramesh; Behera, Meenakshi; Ranjan, Rajesh

    2015-07-01

    Genetic diversity of 49 maize inbreds was assessed using twelve ISSR primers. A wide variation in PCR products was revealed in terms of size (280 to 3000 bp), extent of polymorphism (94.87%) and number of bands (4-9). As a whole, 78 ISSR bands were produced (including four monomorphic bands) with an average of 6.5 bands per primer and the maximum number of bands (9) being produced by primer OUAT-8. Five ISSR primers (OUAT-8, OUAT-9, OUAT-15, OUAT 17 and OUAT-18) revealed higher PIC value (around 0.70) along with 100% polymorphism indicating better allelic diversity. While, ISSR primer OUAT-15 revealed higher number of polymorphic bands (8) with 100% polymorphism as well as considerably high PIC and Rp values. Thus, such an informative and discriminative primer is of immense value for the study of genetic diversity in a set of maize genotypes. The similarity index values ranged from 0.3 to 0.9 with an average of 0.522 and BQPM-1-14 maintained the highest genetic distance as revealed from its lowest average similarity coefficient value (0.393) with rest of the genotypes. BQPM 1-14, BQPM 1-8, BQPM 3-10, BQPM 6-8 and B 1110-7-2 were identified to be highly divergent among the test inbreds which could be sorted out as valuable materials for heterosis breeding for production of single cross hybrids.

  1. [Assessment of allergenicity of genetically modified food crops].

    PubMed

    Schauzu, M; Pöting, A; Rubin, D; Lampen, A

    2012-03-01

    The placing on the European Union's market of genetically modified crops requires authorization by the European Commission which is based on the proof that the derived foods are as safe as their conventional counterparts. The assessment of potential allergenicity is part of the necessary investigations recommended in the updated Guidance Document of the Scientific Panel on Genetically Modified Organisms (GMO) of the European Food Safety Authority (EFSA), which is based on internationally agreed recommendations. All genetically modified crops which so far have been authorized in the European Union were evaluated by the EFSA GMO Panel which considered it unlikely that their overall allergenicity has been altered.

  2. Genetic Determinants for Enzymatic Digestion of Lignocellulosic Biomass Are Independent of Those for Lignin Abundance in a Maize Recombinant Inbred Population

    SciTech Connect

    Penning, Bryan W.; Sykes, Robert W.; Babcock, Nicholas C.; Dugard, Christopher K.; Held, Michael A.; Klimek, John F.; Shreve, Jacob T.; Fowler, Matthew; Ziebell, Angela; Davis, Mark F.; Decker, Stephen R.; Turner, Geoffrey B.; Mosier, Nathan S.; Springer, Nathan M.; Thimmapuram, Jyothi; Weil, Clifford F.; McCann, Maureen C.; Carpita, Nicholas C.

    2014-06-27

    Biotechnological approaches to reduce or modify lignin in biomass crops are predicated on the assumption that it is the principal determinant of the recalcitrance of biomass to enzymatic digestion for biofuels production. We defined quantitative trait loci (QTL) in the Intermated B73 x 3 Mo17 recombinant inbred maize (Zea mays) population using pyrolysis molecular-beam mass spectrometry to establish stem lignin content and an enzymatic hydrolysis assay to measure glucose and xylose yield. Among five multiyear QTL for lignin abundance, two for 4-vinylphenol abundance, and four for glucose and/or xylose yield, not a single QTL for aromatic abundance and sugar yield was shared. A genome-wide association study for lignin abundance and sugar yield of the 282- member maize association panel provided candidate genes in the 11 QTL of the B73 and Mo17 parents but showed that many other alleles impacting these traits exist among this broader pool of maize genetic diversity. B73 and Mo17 genotypes exhibited large differences in gene expression in developing stem tissues independent of allelic variation. Combining these complementary genetic approaches provides a narrowed list of candidate genes. A cluster of SCARECROW-LIKE9 and SCARECROW-LIKE14 transcription factor genes provides exceptionally strong candidate genes emerging from the genome-wide association study. In addition to these and genes associated with cell wall metabolism, candidates include several other transcription factors associated with vascularization and fiber formation and components of cellular signaling pathways. Finally, these results provide new insights and strategies beyond the modification of lignin to enhance yields of biofuels from genetically modified biomass.

  3. Genetic Determinants for Enzymatic Digestion of Lignocellulosic Biomass Are Independent of Those for Lignin Abundance in a Maize Recombinant Inbred Population

    DOE PAGES

    Penning, Bryan W.; Sykes, Robert W.; Babcock, Nicholas C.; ...

    2014-06-27

    Biotechnological approaches to reduce or modify lignin in biomass crops are predicated on the assumption that it is the principal determinant of the recalcitrance of biomass to enzymatic digestion for biofuels production. We defined quantitative trait loci (QTL) in the Intermated B73 x 3 Mo17 recombinant inbred maize (Zea mays) population using pyrolysis molecular-beam mass spectrometry to establish stem lignin content and an enzymatic hydrolysis assay to measure glucose and xylose yield. Among five multiyear QTL for lignin abundance, two for 4-vinylphenol abundance, and four for glucose and/or xylose yield, not a single QTL for aromatic abundance and sugar yieldmore » was shared. A genome-wide association study for lignin abundance and sugar yield of the 282- member maize association panel provided candidate genes in the 11 QTL of the B73 and Mo17 parents but showed that many other alleles impacting these traits exist among this broader pool of maize genetic diversity. B73 and Mo17 genotypes exhibited large differences in gene expression in developing stem tissues independent of allelic variation. Combining these complementary genetic approaches provides a narrowed list of candidate genes. A cluster of SCARECROW-LIKE9 and SCARECROW-LIKE14 transcription factor genes provides exceptionally strong candidate genes emerging from the genome-wide association study. In addition to these and genes associated with cell wall metabolism, candidates include several other transcription factors associated with vascularization and fiber formation and components of cellular signaling pathways. Finally, these results provide new insights and strategies beyond the modification of lignin to enhance yields of biofuels from genetically modified biomass.« less

  4. Elucidation of substituted ester group position in octenylsuccinic anhydride modified sugary maize soluble starch.

    PubMed

    Ye, Fan; Miao, Ming; Huang, Chao; Lu, Keyu; Jiang, Bo; Zhang, Tao

    2014-12-03

    The octenylsuccinic groups in esterification-modified sugary maize soluble starches with a low (0.0191) or high (0.0504) degree of substitution (DS) were investigated by amyloglucosidase hydrolysis followed by a combination of chemical and physical analysis. The results showed the zeta-potential remained at approximately the same value regardless of excessive hydrolysis. The weight-average molecular weight decreased rapidly and reached 1.22 × 10(7) and 1.60 × 10(7) g/mol after 120 min for low-DS and high-DS octenylsuccinic anhydride (OSA) modified starch, respectively. The pattern of z-average radius of gyration as well as particle size change was similar to that of Mw, and z-average radius of gyration decreased much more slowly, especially for high-DS OSA starch. Compared to native starch, two characteristic absorption peaks at 1726.76 and 1571.83 cm(-1) were observed in FT-IR spectra, and the intensity of absorption peaks increased with increasing DS. The NMR results showed that OSA starch had several additional peaks at 0.8-3.0 ppm and a shoulder at 5.56 ppm for OSA substituents, which were grafted at O-2 and O-3 positions in soluble starch. The even distribution of OSA groups in the center area of soluble starch particle has been directly shown under CLSM. Most substitutions were located near branching points of soluble starch particles for a low-DS modified starch, whereas the substituted ester groups were located near branching points as well as at the nonreducing ends in OSA starch with a high DS.

  5. Detection of genetically modified organisms in foods by protein- and DNA-based techniques: bridging the methods.

    PubMed

    van Duijn, Gert J; van Biert, Ria; Bleeker-Marcelis, Henriette; Van Boeijen, Ineke; Adan, Abdi Jama; Jhakrie, Soeniei; Hessing, Martin

    2002-01-01

    According to European Commission (EC) Regulation 1139/98, foods and food ingredients that are to be delivered to the final consumer in which either protein or DNA resulting from genetic modification is present, shall be subject to additional specific labeling requirements. Since 1994, genetically altered tomatoes, squash, potatoes, canola, cotton, and soy have been on the market. Recently, insect-resistant and herbicide-tolerant maize varieties have been introduced. Soy and maize are 2 of the most important vegetable crops in the world. During the past 4 years, both protein- and DNA-based methods have been developed and applied for detection of transgenic soy and maize, and their derivatives. For protein-based detection, specific monoclonal and polyclonal antibodies have been developed; for immunochemical detection, Western blot analysis and enzyme-linked immunosorbent assays are the most prominent examples. For detection of genetically modified organisms (GMOs) at the level of DNA, polymerase chain reaction-based methods are mainly used. For these reactions, highly specific primer sets are needed. This study compares the principally different methods. Specificity of methods and the possible risks of false-positive or false-negative results are considered in relation to sampling, matrix effects, and food processing procedures. In addition, quantitative aspects of protein- and DNA-based GM detection methods are presented and discussed. This is especially relevant as EC regulation 49/2000, which defines a threshold for an unintentional comingling of 1%, came into force on April 10, 2000.

  6. [Hygienic characteristics of foodstuffs containing genetically modified components].

    PubMed

    Beliaev, E N; Ivanov, A A; Fokin, M V

    2006-01-01

    The paper analyzes the results of the investigations of raw foods, foodstuffs for genetically modified components, conducted by the state sanitary and epidemiological service of the Russian Federation during its current sanitary inspection. The presented materials cover 2003-2004. The findings suggest that there is a great deal of foods containing genetically modified sources on the market and show the priority groups of foodstuffs and the distribution of these foods on the territory of the Russian Federation.

  7. Genetically modified crops and aquatic ecosystems: considerations for environmental risk assessment and non-target organism testing.

    PubMed

    Carstens, Keri; Anderson, Jennifer; Bachman, Pamela; De Schrijver, Adinda; Dively, Galen; Federici, Brian; Hamer, Mick; Gielkens, Marco; Jensen, Peter; Lamp, William; Rauschen, Stefan; Ridley, Geoff; Romeis, Jörg; Waggoner, Annabel

    2012-08-01

    Environmental risk assessments (ERA) support regulatory decisions for the commercial cultivation of genetically modified (GM) crops. The ERA for terrestrial agroecosystems is well-developed, whereas guidance for ERA of GM crops in aquatic ecosystems is not as well-defined. The purpose of this document is to demonstrate how comprehensive problem formulation can be used to develop a conceptual model and to identify potential exposure pathways, using Bacillus thuringiensis (Bt) maize as a case study. Within problem formulation, the insecticidal trait, the crop, the receiving environment, and protection goals were characterized, and a conceptual model was developed to identify routes through which aquatic organisms may be exposed to insecticidal proteins in maize tissue. Following a tiered approach for exposure assessment, worst-case exposures were estimated using standardized models, and factors mitigating exposure were described. Based on exposure estimates, shredders were identified as the functional group most likely to be exposed to insecticidal proteins. However, even using worst-case assumptions, the exposure of shredders to Bt maize was low and studies supporting the current risk assessments were deemed adequate. Determining if early tier toxicity studies are necessary to inform the risk assessment for a specific GM crop should be done on a case by case basis, and should be guided by thorough problem formulation and exposure assessment. The processes used to develop the Bt maize case study are intended to serve as a model for performing risk assessments on future traits and crops.

  8. Crop management and agronomic context of the Farm Scale Evaluations of genetically modified herbicide-tolerant crops.

    PubMed Central

    Champion, G T; May, M J; Bennett, S; Brooks, D R; Clark, S J; Daniels, R E; Firbank, L G; Haughton, A J; Hawes, C; Heard, M S; Perry, J N; Randle, Z; Rossall, M J; Rothery, P; Skellern, M P; Scott, R J; Squire, G R; Thomas, M R

    2003-01-01

    The Farm Scale Evaluations of genetically modified herbicide-tolerant crops (GMHT) were conducted in the UK from 2000 to 2002 on beet (sugar and fodder), spring oilseed rape and forage maize. The management of the crops studied is described and compared with current conventional commercial practice. The distribution of field sites adequately represented the areas currently growing these crops, and the sample contained sites operated at a range of management intensities, including low intensity. Herbicide inputs were audited, and the active ingredients used and the rates and the timings of applications compared well with current practice for both GMHT and conventional crops. Inputs on sugar beet were lower than, and inputs on spring oilseed rape and forage maize were consistent with, national averages. Regression analysis of herbicide-application strategies and weed emergence showed that inputs applied by farmers increased with weed densities in beet and forage maize. GMHT crops generally received only one herbicide active ingredient per crop, later and fewer herbicide sprays and less active ingredient (for beet and maize) than the conventional treatments. The audit of inputs found no evidence of bias. PMID:14561315

  9. Sampling Strategies for Evaluating the Rate of Adventitious Transgene Presence in Non-Genetically Modified Crop Fields.

    PubMed

    Makowski, David; Bancal, Rémi; Bensadoun, Arnaud; Monod, Hervé; Messéan, Antoine

    2017-02-23

    According to E.U. regulations, the maximum allowable rate of adventitious transgene presence in non-genetically modified (GM) crops is 0.9%. We compared four sampling methods for the detection of transgenic material in agricultural non-GM maize fields: random sampling, stratified sampling, random sampling + ratio reweighting, random sampling + regression reweighting. Random sampling involves simply sampling maize grains from different locations selected at random from the field concerned. The stratified and reweighting sampling methods make use of an auxiliary variable corresponding to the output of a gene-flow model (a zero-inflated Poisson model) simulating cross-pollination as a function of wind speed, wind direction, and distance to the closest GM maize field. With the stratified sampling method, an auxiliary variable is used to define several strata with contrasting transgene presence rates, and grains are then sampled at random from each stratum. With the two methods involving reweighting, grains are first sampled at random from various locations within the field, and the observations are then reweighted according to the auxiliary variable. Data collected from three maize fields were used to compare the four sampling methods, and the results were used to determine the extent to which transgene presence rate estimation was improved by the use of stratified and reweighting sampling methods. We found that transgene rate estimates were more accurate and that substantially smaller samples could be used with sampling strategies based on an auxiliary variable derived from a gene-flow model.

  10. Discovery and purification of a fungal protease secreted by Bipolaris zeicola that modifies maize seed endochitinase

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Healthy maize seeds have two basic endochitinases, chitA and chitB, with antifungal properties. A comparison of the isoenzyme profiles of symptomatic fungal-infested maize seeds, removed at harvest from ears that we wound inoculated in the late milk stage of maturity with one of several common ear-...

  11. Recombination in diverse maize is stable, predictable, and associated with genetic load.

    PubMed

    Rodgers-Melnick, Eli; Bradbury, Peter J; Elshire, Robert J; Glaubitz, Jeffrey C; Acharya, Charlotte B; Mitchell, Sharon E; Li, Chunhui; Li, Yongxiang; Buckler, Edward S

    2015-03-24

    Among the fundamental evolutionary forces, recombination arguably has the largest impact on the practical work of plant breeders. Varying over 1,000-fold across the maize genome, the local meiotic recombination rate limits the resolving power of quantitative trait mapping and the precision of favorable allele introgression. The consequences of low recombination also theoretically extend to the species-wide scale by decreasing the power of selection relative to genetic drift, and thereby hindering the purging of deleterious mutations. In this study, we used genotyping-by-sequencing (GBS) to identify 136,000 recombination breakpoints at high resolution within US and Chinese maize nested association mapping populations. We find that the pattern of cross-overs is highly predictable on the broad scale, following the distribution of gene density and CpG methylation. Several large inversions also suppress recombination in distinct regions of several families. We also identify recombination hotspots ranging in size from 1 kb to 30 kb. We find these hotspots to be historically stable and, compared with similar regions with low recombination, to have strongly differentiated patterns of DNA methylation and GC content. We also provide evidence for the historical action of GC-biased gene conversion in recombination hotspots. Finally, using genomic evolutionary rate profiling (GERP) to identify putative deleterious polymorphisms, we find evidence for reduced genetic load in hotspot regions, a phenomenon that may have considerable practical importance for breeding programs worldwide.

  12. Stable Patterns of CENH3 Occupancy Through Maize Lineages Containing Genetically Similar Centromeres

    PubMed Central

    Gent, Jonathan I.; Wang, Kai; Jiang, Jiming; Dawe, R. Kelly

    2015-01-01

    While the approximate chromosomal position of centromeres has been identified in many species, little is known about the dynamics and diversity of centromere positions within species. Multiple lines of evidence indicate that DNA sequence has little or no impact in specifying centromeres in maize and in most multicellular organisms. Given that epigenetically defined boundaries are expected to be dynamic, we hypothesized that centromere positions would change rapidly over time, which would result in a diversity of centromere positions in isolated populations. To test this hypothesis, we used CENP-A/cenH3 (CENH3 in maize) chromatin immunoprecipitation to define centromeres in breeding pedigrees that included the B73 inbred as a common parent. While we found a diversity of CENH3 profiles for centromeres with divergent sequences that were not inherited from B73, the CENH3 profiles from centromeres that were inherited from B73 were indistinguishable from each other. We propose that specific genetic elements in centromeric regions favor or inhibit CENH3 accumulation, leading to reproducible patterns of CENH3 occupancy. These data also indicate that dramatic shifts in centromere position normally originate from accumulated or large-scale genetic changes rather than from epigenetic positional drift. PMID:26063660

  13. Influence of galactooligosaccharides and modified waxy maize starch on some attributes of yogurt.

    PubMed

    Prasad, Laxmi N; Sherkat, Frank; Shah, Nagendra P

    2013-01-01

    This study examined the influence of galactooligosaccharides (GOS) and modified waxy maize starch (MWMS) addition on the growth of starter cultures, and syneresis and firmness of low-fat yogurt during storage for 28 d at 4 °C. The control yogurt (CY) was prepared without any prebiotics. Incorporation of 2.0% (w/v) GOS improved the growth of L. delbrueckii ssp. bulgaricus ATCC 11842 resulting in a shorter fermentation time. There was a significant (P < 0.05) increase in proteolysis in yogurt made with GOS (GOSY) as measured by absorbance value (0.728). Addition of GOS resulted in higher (P < 0.05) concentration of lactic and acetic acids in comparison with that of MWMSY and the CY up to day 14, thereafter, the product showed a decrease in lactic acid content in all 3 batches until the end of storage. The level of syneresis was the lowest (2.14%) in MWMSY as compared with that of GOSY (2.35%) and CY (2.53%). There was no statistically significant (P > 0.05) difference in the firmness among the 3 types of yogurt.

  14. Genetic architecture of rind penetrometer resistance in two maize recombinant inbred line populations

    PubMed Central

    2014-01-01

    Background Maize (Zea Mays L.) is one of the most important cereal crops worldwide and provides food for billions of people. Stalk lodging can greatly undermine the standability of maize plants and therefore decrease crop yields. Rind penetrometer resistance is an effective and reliable method for evaluating maize stalk strength, which is highly correlated with stalk lodging resistance. In this study, two recombinant inbred line populations were constructed from crosses between the H127R and Chang7-2 lines, and between the B73 and By804 lines. We genotyped these two populations and their parents using 3,072 single nucleotide polymorphism markers and performed phenotypic assessment of rind penetrometer resistance in multiple environments to dissect the genetic architecture of rind penetrometer resistance in maize. Results Based on two linkage maps of 1,397.1 and 1,600.4 cM with average interval of 1.7 and 2.1 cM between adjacent makers, respectively, seven quantitative trait loci (QTL) for rind penetrometer resistance were detected in the two recombinant inbred line populations. These QTL were distributed in seven genomic regions, and each accounted for 4.4–18.9% of the rind penetrometer resistance variation. The QTL with the largest effect on rind penetrometer resistance, qRPR3-1, was located on chromosome 3 with the flanking markers PZE-103123325 and SYN23245. This locus was further narrowed down to a 3.1-Mb interval by haplotype analysis using high-density markers in the target region. Within this interval, four genes associated with the biosynthesis of cell wall components were considered as potential candidate genes for the rind penetrometer resistance effect. Conclusions The inheritance of rind penetrometer resistance is rather complex. A few large-effect quantitative trait loci, together with a several minor-effect QTL, contributed to the phenotypic variation in rind penetrometer resistance in the two recombinant inbred line populations that were examined

  15. Biophysical and genetic aspects of light-potentiated gravitropic curvature in the maize primary root

    SciTech Connect

    Fantin, D.M.

    1991-04-01

    This thesis explores issues related to light-induced gravitotropic curvature in maize primary roots, such as the root cap as the potential photosensor, entrainment by light of curvature in the gravistimulated root, and the possibility of genetic control of bending response variation. Central to this thesis is a mathematical model, emphasizing physical forces and molecular flows, linking the stages of light-stimulated gravitropic curvature. The model assumes a growth inhibitor is produced in the root cap, transported by diffusion to the extension zone, transported by convection around the extension zone where it retards growth at a rate proportional to its concentration. Model predictions were compared to experimental data to evaluate these assumptions. The root cap is shown to be the photosensor, and genetic crosses show that more than two genes must control the bending response. 140 refs., 31 figs., 11 tabs.

  16. Fine scale genetic structure in the wild ancestor of maize (Zea mays ssp. parviglumis).

    PubMed

    Van Heerwaarden, Joost; Ross-Ibarra, Jeffrey; Doebley, John; Glaubitz, Jeffrey C; González, Jose De Jesús Sánchez; Gaut, Brandon S; Eguiarte, Luis E

    2010-03-01

    Analysis of fine scale genetic structure in continuous populations of outcrossing plant species has traditionally been limited by the availability of sufficient markers. We used a set of 468 SNPs to characterize fine-scale genetic structure within and between two dense stands of the wild ancestor of maize, teosinte (Zea mays ssp. parviglumis). Our analyses confirmed that teosinte is highly outcrossing and showed little population structure over short distances. We found that the two populations were clearly genetically differentiated, although the actual level of differentiation was low. Spatial autocorrelation of relatedness was observed within both sites but was somewhat stronger in one of the populations. Using principal component analysis, we found evidence for significant local differentiation in the population with stronger spatial autocorrelation. This differentiation was associated with pronounced shifts in the first two principal components along the field. These shifts corresponded to changes in allele frequencies, potentially due to local topographical features. There was little evidence for selection at individual loci as a contributing factor to differentiation. Our results demonstrate that significant local differentiation may, but need not, co-occur with spatial autocorrelation of relatedness. The present study represents one of the most detailed analyses of local genetic structure to date and provides a benchmark for future studies dealing with fine scale patterns of genetic diversity in natural plant populations.

  17. [Safety assessment of foods derived from genetically modified plants].

    PubMed

    Pöting, A; Schauzu, M

    2010-06-01

    The placing of genetically modified plants and derived food on the market falls under Regulation (EC) No. 1829/2003. According to this regulation, applicants need to perform a safety assessment according to the Guidance Document of the Scientific Panel on Genetically Modified Organisms of the European Food Safety Authority (EFSA), which is based on internationally agreed recommendations. This article gives an overview of the underlying legislation as well as the strategy and scientific criteria for the safety assessment, which should generally be based on the concept of substantial equivalence and carried out in relation to an unmodified conventional counterpart. Besides the intended genetic modification, potential unintended changes also have to be assessed with regard to potential adverse effects for the consumer. All genetically modified plants and derived food products, which have been evaluated by EFSA so far, were considered to be as safe as products derived from the respective conventional plants.

  18. New multiplex PCR methods for rapid screening of genetically modified organisms in foods.

    PubMed

    Datukishvili, Nelly; Kutateladze, Tamara; Gabriadze, Inga; Bitskinashvili, Kakha; Vishnepolsky, Boris

    2015-01-01

    We present novel multiplex PCR methods for rapid and reliable screening of genetically modified organisms (GMOs). New designed PCR primers targeting four frequently used GMO specific sequences permitted identification of new DNA markers, in particular 141 bp fragment of cauliflower mosaic virus (CaMV) 35S promoter, 224 bp fragment of Agrobacterium tumefaciens nopaline synthase (NOS) terminator, 256 bp fragment of 5-enolppyruvylshikimate-phosphate synthase (epsps) gene and 258 bp fragment of Cry1Ab delta-endotoxin (cry1Ab) gene for GMO screening. The certified reference materials containing Roundup Ready soybean (RRS) and maize MON 810 were applied for the development and optimization of uniplex and multiplex PCR systems. Evaluation of amplification products by agarose gel electrophoresis using negative and positive controls confirmed high specificity and sensitivity at 0.1% GMO for both RRS and MON 810. The fourplex PCR was developed and optimized that allows simultaneous detection of three common transgenic elements, such as: CaMV 35S promoter, NOS terminator, epsps gene together with soybean-specific lectin gene. The triplex PCR developed enables simultaneous identification of transgenic elements, such as: 35S promoter and cry1Ab gene together with maize zein gene. The analysis of different processed foods demonstrated that multiplex PCR methods developed in this study are useful for accurate and fast screening of GM food products.

  19. Use of Carabids for the Post-Market Environmental Monitoring of Genetically Modified Crops.

    PubMed

    Skoková Habuštová, Oxana; Svobodová, Zdeňka; Cagáň, Ľudovít; Sehnal, František

    2017-03-29

    Post-market environmental monitoring (PMEM) of genetically modified (GM) crops is required by EU legislation and has been a subject of debate for many years; however, no consensus on the methodology to be used has been reached. We explored the suitability of carabid beetles as surrogates for the detection of unintended effects of GM crops in general PMEM surveillance. Our study combines data on carabid communities from five maize field trials in Central Europe. Altogether, 86 species and 58,304 individuals were collected. Modeling based on the gradual elimination of the least abundant species, or of the fewest categories of functional traits, showed that a trait-based analysis of the most common species may be suitable for PMEM. Species represented by fewer than 230 individuals (all localities combined) should be excluded and species with an abundance higher than 600 should be preserved for statistical analyses. Sixteen species, representing 15 categories of functional traits fulfill these criteria, are typical dominant inhabitants of agroecocoenoses in Central Europe, are easy to determine, and their functional classification is well known. The effect of sampling year is negligible when at least four samples are collected during maize development beginning from 1 April. The recommended methodology fulfills PMEM requirements, including applicability to large-scale use. However, suggested thresholds of carabid comparability should be verified before definitive conclusions are drawn.

  20. [Identification of genetically modified vegetable sources in food and feed using hydrogel oligonucleotide microchip].

    PubMed

    Griadunov, D A; Getman, I A; Chizhova, S I; Mikhaĭlovich, V M; Zasedatelev, A S; Romanov, G A

    2011-01-01

    A method of multiplex polymerase chain reaction (PCR) followed by the hybridization on a hydrogel oligonucleotide biochip was developed for simultaneous identification of ten different transgenic elements of plant DNA in feed and food products. The biochip contained 22 immobilized probes intended for (i) detection of plant DNA; (ii) plant species determination (soybean, maize, potato, rice); (iii) identification of transgenic elements, including 35S CaMV, 35S FMV, rice actine gene promoters, nos, 35S CaMV, ocs, pea rbcS1 gene terminators, and bar, gus, nptII marker genes. The limit of detection was 0.5% of genetically modified (GM) soybean and maize in analyzed samples. Identification of transgenic DNA in food and feed products using either the developed approach or real-time PCR led to virtually identical results. The assay can be used for selection of GM samples by screening food and feed products for subsequent quantitative determination of the GM component based on the identified transgene.

  1. Detection limits of the strip test and PCR for genetically modified corn in Brazil.

    PubMed

    Nascimento, V E; Von Pinho, É V R; Von Pinho, R G; do Nascimento, A D

    2012-08-16

    Brazilian legislation establishes a labeling limit for products that contain more than 1% material from genetically modified organisms (GMOs). We assessed the sensitivity of the lateral flow strip test in detection of the GMO corn varieties Bt11 and MON810 and the specificity and sensitivity of PCR techniques for their detection. For the strip test, the GMO seeds were mixed with conventional seeds at levels of 0.2, 0.4 and 0.8% for Bt11, and 0.4, 0.8 and 1.6% for MON810. Three different methodologies were assessed and whole seeds, their endosperm and embryonic axis were used. For the PCR technique, the GMO seeds of each of the two varieties were mixed with conventional seeds at levels of 20, 10, 5, 2, 1, and 0.5%. The seeds were ground and the DNA extracted. For detection of the GMO material, specific primers were used for MON810 and Bt11 and maize zein as an endogenous control. The sensitivity of the strip test varied for both maize varieties and methodologies. The test was positive for Bt11 only at 0.8%, in contrast with the detection limit of 0.4% indicated by the manufacturer. In the multiplex PCR, the primers proved to be specific for the different varieties. These varieties were detected in samples with one GMO seed in 100. Thus, this technique proved to be efficient in detecting contaminations equal to or greater than 1%.

  2. New multiplex PCR methods for rapid screening of genetically modified organisms in foods

    PubMed Central

    Datukishvili, Nelly; Kutateladze, Tamara; Gabriadze, Inga; Bitskinashvili, Kakha; Vishnepolsky, Boris

    2015-01-01

    We present novel multiplex PCR methods for rapid and reliable screening of genetically modified organisms (GMOs). New designed PCR primers targeting four frequently used GMO specific sequences permitted identification of new DNA markers, in particular 141 bp fragment of cauliflower mosaic virus (CaMV) 35S promoter, 224 bp fragment of Agrobacterium tumefaciens nopaline synthase (NOS) terminator, 256 bp fragment of 5-enolppyruvylshikimate-phosphate synthase (epsps) gene and 258 bp fragment of Cry1Ab delta-endotoxin (cry1Ab) gene for GMO screening. The certified reference materials containing Roundup Ready soybean (RRS) and maize MON 810 were applied for the development and optimization of uniplex and multiplex PCR systems. Evaluation of amplification products by agarose gel electrophoresis using negative and positive controls confirmed high specificity and sensitivity at 0.1% GMO for both RRS and MON 810. The fourplex PCR was developed and optimized that allows simultaneous detection of three common transgenic elements, such as: CaMV 35S promoter, NOS terminator, epsps gene together with soybean-specific lectin gene. The triplex PCR developed enables simultaneous identification of transgenic elements, such as: 35S promoter and cry1Ab gene together with maize zein gene. The analysis of different processed foods demonstrated that multiplex PCR methods developed in this study are useful for accurate and fast screening of GM food products. PMID:26257724

  3. Detection of genetically modified organisms in foreign-made processed foods containing corn and potato.

    PubMed

    Monma, Kimio; Araki, Rie; Sagi, Naoki; Satoh, Masaki; Ichikawa, Hisatsugu; Satoh, Kazue; Tobe, Takashi; Kamata, Kunihiro; Hino, Akihiro; Saito, Kazuo

    2005-06-01

    Investigations of the validity of labeling regarding genetically modified (GM) products were conducted using polymerase chain reaction (PCR) methods for foreign-made processed foods made from corn and potato purchased in the Tokyo area and in the USA. Several kinds of GM crops were detected in 12 of 32 samples of processed corn samples. More than two GM events for which safety reviews have been completed in Japan were simultaneously detected in 10 samples. GM events MON810 and Bt11 were most frequently detected in the samples by qualitative PCR methods. MON810 was detected in 11 of the 12 samples, and Bt11 was detected in 6 of the 12 samples. In addition, Roundup Ready soy was detected in one of the 12 samples. On the other hand, CBH351, for which the safety assessment was withdrawn in Japan, was not detected in any of the 12 samples. A trial quantitative analysis was performed on six of the GM maize qualitatively positive samples. The estimated amounts of GM maize in these samples ranged from 0.2 to 2.8%, except for one sample, which contained 24.1%. For this sample, the total amount found by event-specific quantitative analysis was 23.8%. Additionally, Roundup Ready soy was detected in one sample of 21 potato-processed foods, although GM potatoes were not detected in any sample.

  4. Genetic control of morphometric diversity in the maize shoot apical meristem

    PubMed Central

    Leiboff, Samuel; Li, Xianran; Hu, Heng-Cheng; Todt, Natalie; Yang, Jinliang; Li, Xiao; Yu, Xiaoqing; Muehlbauer, Gary J.; Timmermans, Marja C. P.; Yu, Jianming; Schnable, Patrick S.; Scanlon, Michael J.

    2015-01-01

    The maize shoot apical meristem (SAM) comprises a small pool of stem cells that generate all above-ground organs. Although mutational studies have identified genetic networks regulating SAM function, little is known about SAM morphological variation in natural populations. Here we report the use of high-throughput image processing to capture rich SAM size variation within a diverse maize inbred panel. We demonstrate correlations between seedling SAM size and agronomically important adult traits such as flowering time, stem size and leaf node number. Combining SAM phenotypes with 1.2 million single nucleotide polymorphisms (SNPs) via genome-wide association study reveals unexpected SAM morphology candidate genes. Analyses of candidate genes implicated in hormone transport, cell division and cell size confirm correlations between SAM morphology and trait-associated SNP alleles. Our data illustrate that the microscopic seedling SAM is predictive of adult phenotypes and that SAM morphometric variation is associated with genes not previously predicted to regulate SAM size. PMID:26584889

  5. Genome-Wide Association Study Reveals the Genetic Basis of Stalk Cell Wall Components in Maize

    PubMed Central

    Hu, Xiaojiao; Liu, Zhifang; Wu, Yujin; Huang, Changling

    2016-01-01

    Lignin, cellulose and hemicellulose are the three main components of the plant cell wall and can impact stalk quality by affecting cell wall structure and strength. In this study, we evaluated the lignin (LIG), cellulose (CEL) and hemicellulose (HC) contents in maize using an association mapping panel that included 368 inbred lines in seven environments. A genome-wide association study using approximately 0.56 million SNPs with a minor allele frequency of 0.05 identified 22, 18 and 24 loci significantly associated with LIG, CEL and HC at P < 1.0×10−4, respectively. The allelic variation of each significant association contributed 4 to 7% of the phenotypic variation. Candidate genes identified by GWAS mainly encode enzymes involved in cell wall metabolism, transcription factors, protein kinase and protein related to other biological processes. Among the association signals, six candidate genes had pleiotropic effects on lignin and cellulose content. These results provide valuable information for better understanding the genetic basis of stalk cell wall components in maize. PMID:27479588

  6. Genetic modifiers of obesity and bariatric surgery outcomes.

    PubMed

    Sevilla, Samantha; Hubal, Monica J

    2014-02-01

    Obesity is a highly heritable trait. While acute and chronic changes in body weight or obesity-related comorbidities are heavily influenced by environmental factors, there are still strong genomic modifiers that help account for inter-subject variability in baseline traits and in response to interventions. This review is intended to provide an up-to-date overview of our current understanding of genetic influences on obesity, with emphasis on genetic modifiers of baseline traits and responses to intervention. We begin by reviewing how genetic variants can influence obesity. We then examine genetic modifiers of weight loss via different intervention strategies, focusing on known and potential modifiers of surgical weight loss outcomes. We will pay particular attention to the effects of patient age on outcomes, addressing the risks and benefits of adopting early intervention strategies. Finally, we will discuss how the field of bariatric surgery can leverage knowledge of genetic modifiers to adopt a personalized medicine approach for optimal outcomes across this widespread and diverse patient population.

  7. [A Study of the Relationship Among Genetic Distances, NIR Spectra Distances, and NIR-Based Identification Model Performance of the Seeds of Maize Iinbred Lines].

    PubMed

    Liu, Xu; Jia, Shi-qiang; Wang, Chun-ying; Liu, Zhe; Gu, Jian-cheng; Zhai, Wei; Li, Shao-ming; Zhang, Xiao-dong; Zhu, De-hai; Huang, Hua-jun; An, Dong

    2015-09-01

    This paper explored the relationship among genetic distances, NIR spectra distances and NIR-based identification model performance of the seeds of maize inbred lines. Using 3 groups (total 15 pairs) of maize inbred lines whose genetic distaches are different as experimental materials, we calculates the genetic distance between these seeds with SSR markers and uses Euclidean distance between distributed center points of maize NIR spectrum in the PCA space as the distances of NIR spectrum. BPR method is used to build identification model of inbred lines and the identification accuracy is used as a measure of model identification performance. The results showed that, the correlation of genetic distance and spectra distancesis 0.9868, and it has a correlation of 0.9110 with the identification accuracy, which is highly correlated. This means near-Infrared spectrum of seedscan reflect genetic relationship of maize inbred lines. The smaller the genetic distance, the smaller the distance of spectrum, the poorer ability of model to identify. In practical application, near infrared spectrum analysis technology has the potential to be used to analyze maize inbred genetic relations, contributing much to genetic breeding, identification of species, purity sorting and so on. What's more, when creating a NIR-based identification model, the impact of the maize inbred lines which have closer genetic relationship should be fully considered.

  8. The relationship between parental genetic or phenotypic divergence and progeny variation in the maize nested association mapping population.

    PubMed

    Hung, H-Y; Browne, C; Guill, K; Coles, N; Eller, M; Garcia, A; Lepak, N; Melia-Hancock, S; Oropeza-Rosas, M; Salvo, S; Upadyayula, N; Buckler, E S; Flint-Garcia, S; McMullen, M D; Rocheford, T R; Holland, J B

    2012-05-01

    Appropriate selection of parents for the development of mapping populations is pivotal to maximizing the power of quantitative trait loci detection. Trait genotypic variation within a family is indicative of the family's informativeness for genetic studies. Accurate prediction of the most useful parental combinations within a species would help guide quantitative genetics studies. We tested the reliability of genotypic and phenotypic distance estimators between pairs of maize inbred lines to predict genotypic variation for quantitative traits within families derived from biparental crosses. We developed 25 families composed of ~200 random recombinant inbred lines each from crosses between a common reference parent inbred, B73, and 25 diverse maize inbreds. Parents and families were evaluated for 19 quantitative traits across up to 11 environments. Genetic distances (GDs) among parents were estimated with 44 simple sequence repeat and 2303 single-nucleotide polymorphism markers. GDs among parents had no predictive value for progeny variation, which is most likely due to the choice of neutral markers. In contrast, we observed for about half of the traits measured a positive correlation between phenotypic parental distances and within-family genetic variance estimates. Consequently, the choice of promising segregating populations can be based on selecting phenotypically diverse parents. These results are congruent with models of genetic architecture that posit numerous genes affecting quantitative traits, each segregating for allelic series, with dispersal of allelic effects across diverse genetic material. This architecture, common to many quantitative traits in maize, limits the predictive value of parental genotypic or phenotypic values on progeny variance.

  9. Silicon modifies root anatomy, and uptake and subcellular distribution of cadmium in young maize plants

    PubMed Central

    Vaculík, Marek; Landberg, Tommy; Greger, Maria; Luxová, Miroslava; Stoláriková, Miroslava; Lux, Alexander

    2012-01-01

    Background and Aims Silicon (Si) has been shown to ameliorate the negative influence of cadmium (Cd) on plant growth and development. However, the mechanism of this phenomenon is not fully understood. Here we describe the effect of Si on growth, and uptake and subcellular distribution of Cd in maize plants in relation to the development of root tissues. Methods Young maize plants (Zea mays) were cultivated for 10 d hydroponically with 5 or 50 µm Cd and/or 5 mm Si. Growth parameters and the concentrations of Cd and Si were determined in root and shoot by atomic absorption spectrometry or inductively coupled plasma mass spectroscopy. The development of apoplasmic barriers (Casparian bands and suberin lamellae) and vascular tissues in roots were analysed, and the influence of Si on apoplasmic and symplasmic distribution of 109Cd applied at 34 nm was investigated between root and shoot. Key Results Si stimulated the growth of young maize plants exposed to Cd and influenced the development of Casparian bands and suberin lamellae as well as vascular tissues in root. Si did not affect the distribution of apoplasmic and symplasmic Cd in maize roots, but considerably decreased symplasmic and increased apoplasmic concentration of Cd in maize shoots. Conclusions Differences in Cd uptake of roots and shoots are probably related to the development of apoplasmic barriers and maturation of vascular tissues in roots. Alleviation of Cd toxicity by Si might be attributed to enhanced binding of Cd to the apoplasmic fraction in maize shoots. PMID:22455991

  10. Environmental distribution and genetic diversity of vegetative compatibility groups determine biocontrol strategies to mitigate aflatoxin contamination of maize by Aspergillus flavus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize infected by aflatoxin-producing Aspergillus flavus may become contaminated with aflatoxins and as a result, threaten human health, food security, and farmers’ income in developing countries where maize is a staple. Environmental distribution and genetic diversity of A. flavus can influence the...

  11. The Germplasm Enhancement of Maize (GEM) project: A Public-Private Partnership (PPP) to increase genetic diversity in US maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Germplasm Enhancement of Maize (GEM) Project is a mission-oriented, cooperative research effort of the United States Department of Agriculture – Agricultural Research Service (USDA-ARS), land grant universities, private industry, and international agricultural research centers to broaden the ger...

  12. Allelopathic effect of methanolic extracts of genetically modified and non-genetically modified canola on soybean.

    PubMed

    Syed, Kashmala; Shinwari, Zabta Khan

    2016-03-01

    This study on the effect of genetically modified (GM) and non-GM canola on soybean was carried out for physiological and biochemical biosafety assessment of GM canola. Methanolic extracts of GM and non-GM canola were assessed on seed germination and growth of soybean (Glycine max L.) under sterilized conditions. The extracts applied were of 3, 5, and 10% concentrations. The results showed that methanolic extracts of both GM and non-GM canola improved the germination percentage. However, germination rate index was significantly decreased with concomitant increase in mean germination time of soybean. A significant rate of decrease was observed in root fresh weight while increase in shoot length took place; when treatment of GM canola extracts were applied, however, no effect was observed in shoot fresh weight. A significant increase in protein contents, as well as phenolic, carotenoids, proline, and chlorophyll a content, was observed when different GM canola treatments (3, 5, and 10%) were applied to soybean; however, a significant rate of reduction in chlorophyll b content was observed by the application of GM canola treatment. Similar results were observed for superoxide dismutase, peroxidase, and catalase activities. A significant increase in the sugar content levels was observed when GM canola treatments (3, 5, and 10%) were applied to soybean.

  13. Genetically Modified T Cells to Target Glioblastoma

    PubMed Central

    Krebs, Simone; Rodríguez-Cruz, Tania G.; DeRenzo, Christopher; Gottschalk, Stephen

    2013-01-01

    Despite advances in surgical procedures, radiation, and chemotherapy the outcome for patients with glioblastoma (GBM) remains poor. While GBM cells express antigens that are potentially recognized by T cells, GBMs prevent the induction of GBM-specific immune responses by creating an immunosuppressive microenvironment. The advent of gene transfer has allowed the rapid generation of antigen-specific T cells as well as T cells with enhanced effector function. Here we review recent advances in the field of cell therapy with genetically modified T cells and how these advances might improve outcomes for patients with GBM in the future. PMID:24427741

  14. MaizeGDB - Past, present, and future

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Maize Genetics and Genomics Database (MaizeGDB) turns 20 this year. This editorial outlines MaizeGDB's history and connection to the Maize Genetics Cooperation, describes key components of how the MaizeGDB interface will be completely redesigned over the course of the next two years to meet cur...

  15. Broadening Our Portfolio in the Genetic Improvement of Maize Chemical Composition.

    PubMed

    Wen, Weiwei; Brotman, Yariv; Willmitzer, Lothar; Yan, Jianbing; Fernie, Alisdair R

    2016-08-01

    The adoption of recombinant inbred line and introgression line populations, as well as the study of association mapping panels, has greatly accelerated our ability to identify the genes underlying plant phenotypic variance. In tandem, the development of metabolomics approaches has greatly enhanced our ability to comprehensively define cellular chemical composition. As a consequence, breeding for chemical composition is being extended beyond our traditional targets of oil and protein to include components such as essential amino acids, vitamins, and antioxidant secondary metabolites with considerable purported consequences for human health. Here, we review the above-mentioned developments paying particular attention to the genetic architecture of metabolic traits as well as updating the perspective for utilizing metabolomics in maize improvement.

  16. Is genetically modified crop the answer for the next green revolution?

    PubMed

    Basu, Saikat Kumar; Dutta, Madhuleema; Goyal, Aakash; Bhowmik, Pankaj Kumar; Kumar, Jitendra; Nandy, Sanjib; Scagliusi, Sandra Mansun; Prasad, Rajib

    2010-01-01

    Post-green revolution advances made in biotechnology paved the way of cultivating the high-yielding, stress and disease resistant genetically modified (GM) varieties of wheat, rice, maize cotton and several other crops. The recent rapid commercialization of the genetically modified crops in Asia, Americas and Australia indicates the potentiality of this new technology. GM crops give higher yields and are rich in nutritional values containing vitamins and minerals and can thus can help to alleviate hunger and malnutrition of the growing population in the under developed and developing countries. It could also be possible to develop more biotic and abiotic stress resistant genotypes in these crops where it was difficult to develop due to the unavailability of genes of resistance in the crossing germplasms. However, further research and investigations are needed to popularize the cultivation of these crops in different parts of the world. This review provides an insight of the impact of GM crops on contemporary agriculture across the past few decades, traces its' history across time, highlights new achievements and breakthroughs and discusses the future implication of this powerful technology in the coming few decades.

  17. Transcriptional silencing of heterologous anther promoters in maize: a genetic method to replace detasseling for seed production.

    PubMed

    Cigan, A Mark; Haug-Collet, Kristin; Clapp, Joshua

    2014-09-01

    The promoter of the maize male fertility gene ZmMs45, and other anther-specific maize promoters, was previously shown to be transcriptionally silenced by constitutively expressed promoter-inverted repeat RNAs (pIRs). In addition, ZmMS45pIR-mediated male sterility was reversed by co-expression of Ms45 transcribed by promoters not targeted by pIR RNA silencing. In this report, male fertility was restored to ms45 maize by fusing non-maize inflorescence promoters to the ZmMS45 coding region. This complementation assay also established that these rice or Arabidopsis promoters, when expressed as pIRs, functioned to silence sequence identical promoters. These observations were exploited to develop a genetic method to replace maize detasseling during hybrid seed production. In this system, the ZmMS45 coding region was fused to one of two dissimilar non-maize promoters to generate paired sets of ms45 recessive inbred parents which could be self-pollinated and maintained independently. Linked to each unique Ms45 gene was a non-maize pIR which targeted the promoter transcribing the Ms45 copy contained in the paired inbred parent plant. A cross of these pairs brings the dissimilar pIR cassettes together and resulted in silencing both transformed copies of Ms45. The net result uncovers the ms45 allele carried by the inbreds yielding male sterile progeny. The application of heterologous promoters and transcriptional silencing in plants provides an alternative to post-transcriptional gene silencing as a means to restore and silence gene function in plants.

  18. Genetically engineered maize plants reveal distinct costs and benefits of constitutive volatile emissions in the field.

    PubMed

    Robert, Christelle Aurélie Maud; Erb, Matthias; Hiltpold, Ivan; Hibbard, Bruce Elliott; Gaillard, Mickaël David Philippe; Bilat, Julia; Degenhardt, Jörg; Cambet-Petit-Jean, Xavier; Turlings, Ted Christiaan Joannes; Zwahlen, Claudia

    2013-06-01

    Genetic manipulation of plant volatile emissions is a promising tool to enhance plant defences against herbivores. However, the potential costs associated with the manipulation of specific volatile synthase genes are unknown. Therefore, we investigated the physiological and ecological effects of transforming a maize line with a terpene synthase gene in field and laboratory assays, both above- and below ground. The transformation, which resulted in the constitutive emission of (E)-β-caryophyllene and α-humulene, was found to compromise seed germination, plant growth and yield. These physiological costs provide a possible explanation for the inducibility of an (E)-β-caryophyllene-synthase gene in wild and cultivated maize. The overexpression of the terpene synthase gene did not impair plant resistance nor volatile emission. However, constitutive terpenoid emission increased plant apparency to herbivores, including adults and larvae of the above ground pest Spodoptera frugiperda, resulting in an increase in leaf damage. Although terpenoid overproducing lines were also attractive to the specialist root herbivore Diabrotica virgifera virgifera below ground, they did not suffer more root damage in the field, possibly because of the enhanced attraction of entomopathogenic nematodes. Furthermore, fewer adults of the root herbivore Diabrotica undecimpunctata howardii were found to emerge near plants that emitted (E)-β-caryophyllene and α-humulene. Yet, overall, under the given field conditions, the costs of constitutive volatile production overshadowed its benefits. This study highlights the need for a thorough assessment of the physiological and ecological consequences of genetically engineering plant signals in the field to determine the potential of this approach for sustainable pest management strategies.

  19. ENU mutagenesis to generate genetically modified rat models.

    PubMed

    van Boxtel, Ruben; Gould, Michael N; Cuppen, Edwin; Smits, Bart M G

    2010-01-01

    The rat is one of the most preferred model organisms in biomedical research and has been extremely useful for linking physiology and pathology to the genome. However, approaches to genetically modify specific genes in the rat germ line remain relatively scarce. To date, the most efficient approach for generating genetically modified rats has been the target-selected N-ethyl-N-nitrosourea (ENU) mutagenesis-based technology. Here, we describe the detailed protocols for ENU mutagenesis and mutant retrieval in the rat model organism.

  20. MS-based analytical methodologies to characterize genetically modified crops.

    PubMed

    García-Cañas, Virginia; Simó, Carolina; León, Carlos; Ibáñez, Elena; Cifuentes, Alejandro

    2011-01-01

    The development of genetically modified crops has had a great impact on the agriculture and food industries. However, the development of any genetically modified organism (GMO) requires the application of analytical procedures to confirm the equivalence of the GMO compared to its isogenic non-transgenic counterpart. Moreover, the use of GMOs in foods and agriculture faces numerous criticisms from consumers and ecological organizations that have led some countries to regulate their production, growth, and commercialization. These regulations have brought about the need of new and more powerful analytical methods to face the complexity of this topic. In this regard, MS-based technologies are increasingly used for GMOs analysis to provide very useful information on GMO composition (e.g., metabolites, proteins). This review focuses on the MS-based analytical methodologies used to characterize genetically modified crops (also called transgenic crops). First, an overview on genetically modified crops development is provided, together with the main difficulties of their analysis. Next, the different MS-based analytical approaches applied to characterize GM crops are critically discussed, and include "-omics" approaches and target-based approaches. These methodologies allow the study of intended and unintended effects that result from the genetic transformation. This information is considered to be essential to corroborate (or not) the equivalence of the GM crop with its isogenic non-transgenic counterpart.

  1. Genetically Modified Food: Knowledge and Attitude of Teachers and Students

    NASA Astrophysics Data System (ADS)

    Mohapatra, Animesh K.; Priyadarshini, Deepika; Biswas, Antara

    2010-10-01

    The concepts behind the technology of genetic modification of organisms and its applications are complex. A diverse range of opinions, public concern and considerable media interest accompanies the subject. This study explores the knowledge and attitudes of science teachers and senior secondary biology students about the application of a rapidly expanding technology, genetic engineering, to food production. The results indicated significant difference in understanding of concepts related with genetically engineered food stuffs between teachers and students. The most common ideas about genetically modified food were that cross bred plants and genetically modified plants are not same, GM organisms are produced by inserting a foreign gene into a plant or animal and are high yielding. More teachers thought that genetically engineered food stuffs were unsafe for the environment. Both teachers and students showed number of misconceptions, for example, the pesticidal proteins produced by GM organisms have indirect effects through bioaccumulation, induces production of allergic proteins, genetic engineering is production of new genes, GM plants are leaky sieves and that transgenes are more likely to introgress into wild species than mutated species. In general, more students saw benefits while teachers were cautious about the advantages of genetically engineered food stuffs.

  2. Edible safety requirements and assessment standards for agricultural genetically modified organisms.

    PubMed

    Deng, Pingjian; Zhou, Xiangyang; Zhou, Peng; Du, Zhong; Hou, Hongli; Yang, Dongyan; Tan, Jianjun; Wu, Xiaojin; Zhang, Jinzhou; Yang, Yongcun; Liu, Jin; Liu, Guihua; Li, Yonghong; Liu, Jianjun; Yu, Lei; Fang, Shisong; Yang, Xiaoke

    2008-05-01

    This paper describes the background, principles, concepts and methods of framing the technical regulation for edible safety requirement and assessment of agricultural genetically modified organisms (agri-GMOs) for Shenzhen Special Economic Zone in the People's Republic of China. It provides a set of systematic criteria for edible safety requirements and the assessment process for agri-GMOs. First, focusing on the degree of risk and impact of different agri-GMOs, we developed hazard grades for toxicity, allergenicity, anti-nutrition effects, and unintended effects and standards for the impact type of genetic manipulation. Second, for assessing edible safety, we developed indexes and standards for different hazard grades of recipient organisms, for the influence of types of genetic manipulation and hazard grades of agri-GMOs. To evaluate the applicability of these criteria and their congruency with other safety assessment systems for GMOs applied by related organizations all over the world, we selected some agri-GMOs (soybean, maize, potato, capsicum and yeast) as cases to put through our new assessment system, and compared our results with the previous assessments. It turned out that the result of each of the cases was congruent with the original assessment.

  3. Genetically modified bacteriophages in applied microbiology.

    PubMed

    Bárdy, P; Pantůček, R; Benešík, M; Doškař, J

    2016-09-01

    Bacteriophages represent a simple viral model of basic research with many possibilities for practical application. Due to their ability to infect and kill bacteria, their potential in the treatment of bacterial infection has been examined since their discovery. With advances in molecular biology and gene engineering, the phage application spectrum has been expanded to various medical and biotechnological fields. The construction of bacteriophages with an extended host range or longer viability in the mammalian bloodstream enhances their potential as an alternative to conventional antibiotic treatment. Insertion of active depolymerase genes to their genomes can enforce the biofilm disposal. They can also be engineered to transfer various compounds to the eukaryotic organisms and the bacterial culture, applicable for the vaccine, drug or gene delivery. Phage recombinant lytic enzymes can be applied as enzybiotics in medicine as well as in biotechnology for pathogen detection or programmed cell death in bacterial expression strains. Besides, modified bacteriophages with high specificity can be applied as bioprobes in detection tools to estimate the presence of pathogens in food industry, or utilized in the control of food-borne pathogens as part of the constructed phage-based biosorbents.

  4. Early Institutionalization: Neurobiological Consequences and Genetic Modifiers

    PubMed Central

    Drury, Stacy; McLaughlin, Kate; Almas, Alisa

    2011-01-01

    Children raised in the profound deprivation associated with institutionalization are at elevated risk for negative outcomes across a host of social and cognitive domains. This risk appears to be mitigated by early foster care or adoption into a family setting. Although pervasive developmental problems have been noted in a substantial proportion of previously institutionalized children, marked variation exists in the nature and severity of these deficits. Increasing evidence suggests that institutional deprivation impacts the developing brain, potentially underlying the wide range of outcomes with which it is associated. In the current review we examine the neural consequences of institutionalization and genetic factors associated with differences in outcome in an effort to characterize the consequences of early deprivation at a neurobiological level. Although the effects of institutional deprivation have been studied for more than 50 years much remains unanswered regarding the pathways through which institutionalization impacts child development. Through a more complete and nuanced assessment of the neural correlates of exposure and recovery as well as a better understanding of the individual factors involved we will be better able to delineate the impact of early adversity in the setting of severe social deprivation. PMID:21042937

  5. Zeaxanthin is bioavailable from genetically modified zeaxanthin-rich potatoes.

    PubMed

    Bub, Achim; Möseneder, Jutta; Wenzel, Gerhard; Rechkemmer, Gerhard; Briviba, Karlis

    2008-03-01

    The carotenoid zeaxanthin accumulates in the human macula lutea and protects retinal cells from blue light damage. However, zeaxanthin intake from food sources is low. Increasing zeaxanthin in common foods such as potatoes by traditional plant breeding or by genetic engineering could contribute to an increased intake of this carotenoid and, consequently, to a decreased risk of age-related macular degeneration. Our aim was to investigate whether zeaxanthin from genetically modified zeaxanthin-rich potatoes is bioavailable in humans. Three men participated in this randomized, controlled double-blinded, crossover pilot study. All subjects consumed 1,100 g of mashed potatoes, either genetically modified (Solanum tuberosum L. var. Baltica GM47/18; 3 mg zeaxanthin) or wild-type control potatoes (Solanum tuberosum L. var. Baltica; 0.14 mg zeaxanthin). A second treatment was followed after a 7-day wash-out period. The concentration of zeaxanthin was significantly increased in chylomicrons after consumption of genetically modified potatoes and 0.27 mg of the 3 mg zeaxanthin dose could be detected in chylomicrons. Consumption of control potatoes had no effect on concentrations of zeaxanthin in chylomicrons. After normalization of chylomicron zeaxanthin for plasma triacylglycerol, the time course of zeaxanthin concentrations peaked at 7 h after consumption of genetically modified potatoes. There were no significant differences in the concentrations of other major potato carotenoids such as lutein and beta-carotene in chylomicrons after consumption of genetically modified and wild type control potatoes. Thus, consumption of zeaxanthin-rich potatoes significantly increases chylomicron zeaxanthin concentrations suggesting that potentially such potatoes could be used as an important dietary source of zeaxanthin.

  6. The Genetic Architecture of Maize (Zea mays L.) Kernel Weight Determination

    PubMed Central

    Prado, Santiago Alvarez; López, César G.; Senior, M. Lynn; Borrás, Lucas

    2014-01-01

    Individual kernel weight is an important trait for maize yield determination. We have identified genomic regions controlling this trait by using the B73xMo17 population; however, the effect of genetic background on control of this complex trait and its physiological components is not yet known. The objective of this study was to understand how genetic background affected our previous results. Two nested stable recombinant inbred line populations (N209xMo17 and R18xMo17) were designed for this purpose. A total of 408 recombinant inbred lines were genotyped and phenotyped at two environments for kernel weight and five other traits related to kernel growth and development. All traits showed very high and significant (P < 0.001) phenotypic variability and medium-to-high heritability (0.60−0.90). When N209xMo17 and R18xMo17 were analyzed separately, a total of 23 environmentally stable quantitative trait loci (QTL) and five epistatic interactions were detected for N209xMo17. For R18xMo17, 59 environmentally stable QTL and 17 epistatic interactions were detected. A joint analysis detected 14 stable QTL regardless of the genetic background. Between 57 and 83% of detected QTL were population specific, denoting medium-to-high genetic background effects. This percentage was dependent on the trait. A meta-analysis including our previous B73xMo17 results identified five relevant genomic regions deserving further characterization. In summary, our grain filling traits were dominated by small additive QTL with several epistatic and few environmental interactions and medium-to-high genetic background effects. This study demonstrates that the number of detected QTL and additive effects for different physiologically related grain filling traits need to be understood relative to the specific germplasm. PMID:25237113

  7. Genetic Vulnerability and the Relationship of Commercial Germplasms of Maize in Brazil with the Nested Association Mapping Parents.

    PubMed

    Andrade, Luciano Rogério Braatz de; Fritsche Neto, Roberto; Granato, Ítalo Stefanine Correia; Sant'Ana, Gustavo César; Morais, Pedro Patric Pinho; Borém, Aluízio

    2016-01-01

    A few breeding companies dominate the maize (Zea mays L.) hybrid market in Brazil: Monsanto® (35%), DuPont Pioneer® (30%), Dow Agrosciences® (15%), Syngenta® (10%) and Helix Sementes (4%). Therefore, it is important to monitor the genetic diversity in commercial germplasms as breeding practices, registration and marketing of new cultivars can lead to a significant reduction of the genetic diversity. Reduced genetic variation may lead to crop vulnerabilities, food insecurity and limited genetic gains following selection. The aim of this study was to evaluate the genetic vulnerability risk by examining the relationship between the commercial Brazilian maize germplasms and the Nested Association Mapping (NAM) Parents. For this purpose, we used the commercial hybrids with the largest market share in Brazil and the NAM parents. The hybrids were genotyped for 768 single nucleotide polymorphisms (SNPs), using the Illumina Goldengate® platform. The NAM parent genomic data, comprising 1,536 SNPs for each line, were obtained from the Panzea data bank. The population structure, genetic diversity and the correlation between allele frequencies were analyzed. Based on the estimated effective population size and genetic variability, it was found that there is a low risk of genetic vulnerability in the commercial Brazilian maize germplasms. However, the genetic diversity is lower than those found in the NAM parents. Furthermore, the Brazilian germplasms presented no close relations with most NAM parents, except B73. This indicates that B73, or its heterotic group (Iowa Stiff Stalk Synthetic), contributed to the development of the commercial Brazilian germplasms.

  8. Genetic Vulnerability and the Relationship of Commercial Germplasms of Maize in Brazil with the Nested Association Mapping Parents

    PubMed Central

    Fritsche Neto, Roberto; Granato, Ítalo Stefanine Correia; Sant’Ana, Gustavo César; Morais, Pedro Patric Pinho; Borém, Aluízio

    2016-01-01

    A few breeding companies dominate the maize (Zea mays L.) hybrid market in Brazil: Monsanto® (35%), DuPont Pioneer® (30%), Dow Agrosciences® (15%), Syngenta® (10%) and Helix Sementes (4%). Therefore, it is important to monitor the genetic diversity in commercial germplasms as breeding practices, registration and marketing of new cultivars can lead to a significant reduction of the genetic diversity. Reduced genetic variation may lead to crop vulnerabilities, food insecurity and limited genetic gains following selection. The aim of this study was to evaluate the genetic vulnerability risk by examining the relationship between the commercial Brazilian maize germplasms and the Nested Association Mapping (NAM) Parents. For this purpose, we used the commercial hybrids with the largest market share in Brazil and the NAM parents. The hybrids were genotyped for 768 single nucleotide polymorphisms (SNPs), using the Illumina Goldengate® platform. The NAM parent genomic data, comprising 1,536 SNPs for each line, were obtained from the Panzea data bank. The population structure, genetic diversity and the correlation between allele frequencies were analyzed. Based on the estimated effective population size and genetic variability, it was found that there is a low risk of genetic vulnerability in the commercial Brazilian maize germplasms. However, the genetic diversity is lower than those found in the NAM parents. Furthermore, the Brazilian germplasms presented no close relations with most NAM parents, except B73. This indicates that B73, or its heterotic group (Iowa Stiff Stalk Synthetic), contributed to the development of the commercial Brazilian germplasms. PMID:27780247

  9. Detection of Cry1Ab protein in gastrointestinal contents but not visceral organs of genetically modified Bt11-fed calves.

    PubMed

    Chowdhury, E H; Shimada, N; Murata, H; Mikami, O; Sultana, P; Miyazaki, S; Yoshioka, M; Yamanaka, N; Hirai, N; Nakajima, Y

    2003-03-01

    The fate of insecticidal Cry1Ab protein was examined in the gastrointestinal (GI) contents and visceral organs of calves fed insect-resistant genetically modified maize Bt11. Twelve cross-breed (Japanese black x Holstein) calves were fed either Bt11 or non-genetically modified isoline maize for 90 d. Peripheral blood, rumen juice and feces were collected fortnightly, and GI contents and visceral organs were collected at slaughter at the end of the experiment. Samples were checked for Cry1Ab protein by immunological methods, and visceral organs were examined pathologically. Trace amounts of Cry1Ab protein were detected in the GI contents but not in the liver, spleen, kidney, muscle or mesenteric lymph nodes. No lesions were observed pathologically. Cry1Ab protein in the feces was degraded quickly at atmospheric temperature. These results suggested that only a trace amount of Cry1Ab protein survived passage through the GI tract but was not transferred to liver, spleen, kidney, lymph nodes or muscles.

  10. GenAnneal: Genetically modified Simulated Annealing

    NASA Astrophysics Data System (ADS)

    Tsoulos, Ioannis G.; Lagaris, Isaac E.

    2006-05-01

    A modification of the standard Simulated Annealing (SA) algorithm is presented for finding the global minimum of a continuous multidimensional, multimodal function. We report results of computational experiments with a set of test functions and we compare to methods of similar structure. The accompanying software accepts objective functions coded both in Fortran 77 and C++. Program summaryTitle of program:GenAnneal Catalogue identifier:ADXI_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADXI_v1_0 Program available from: CPC Program Library, Queen's University of Belfast, N. Ireland Computer for which the program is designed and others on which it has been tested: The tool is designed to be portable in all systems running the GNU C++ compiler Installation: University of Ioannina, Greece on Linux based machines Programming language used:GNU-C++, GNU-C, GNU Fortran 77 Memory required to execute with typical data: 200 KB No. of bits in a word: 32 No. of processors used: 1 Has the code been vectorized or parallelized?: No No. of bytes in distributed program, including test data, etc.:84 885 No. of lines in distributed program, including test data, etc.:14 896 Distribution format: tar.gz Nature of physical problem: A multitude of problems in science and engineering are often reduced to minimizing a function of many variables. There are instances that a local optimum does not correspond to the desired physical solution and hence the search for a better solution is required. Local optimization techniques are frequently trapped in local minima. Global optimization is hence the appropriate tool. For example, solving a non-linear system of equations via optimization, employing a "least squares" type of objective, one may encounter many local minima that do not correspond to solutions (i.e. they are far from zero). Typical running time: Depending on the objective function. Method of solution: We modified the process of step selection that the traditional Simulated

  11. An algorithm for the identification of genetically modified animals.

    PubMed

    Forabosco, Flavio; Sundström, Fredrik L; Rydhmer, Lotta

    2013-05-01

    The diffusion of genetically modified (GM) animals has generated a demand for accurate and unique identification to assure compliance with relevant national and international legislation. Individual identification of GM animals is essential to improve safety and traceability, as well as to fulfill the present and future expectations of producers, consumers, and authorities.

  12. Review: Genetically modified plants for the promotion of human health.

    PubMed

    Yonekura-Sakakibara, Keiko; Saito, Kazuki

    2006-12-01

    Plants are attractive biological resources because of their ability to produce a huge variety of chemical compounds, and the familiarity of production in even the most rural settings. Genetic engineering gives plants additional characteristics and value for cultivation and post-harvest. Genetically modified (GM) plants of the "first generation" were conferred with traits beneficial to producers, whereas GM plants in subsequent "generations" are intended to provide beneficial traits for consumers. Golden Rice is a promising example of a GM plant in the second generation, and has overcome a number of obstacles for practical use. Furthermore, consumer-acceptable plants with health-promoting properties that are genetically modified using native genes are being developed. The emerging technology of metabolomics will also support the commercial realization of GM plants by providing comprehensive analyzes of plant biochemical components.

  13. Somatic cell reprogramming-free generation of genetically modified pigs.

    PubMed

    Tanihara, Fuminori; Takemoto, Tatsuya; Kitagawa, Eri; Rao, Shengbin; Do, Lanh Thi Kim; Onishi, Akira; Yamashita, Yukiko; Kosugi, Chisato; Suzuki, Hitomi; Sembon, Shoichiro; Suzuki, Shunichi; Nakai, Michiko; Hashimoto, Masakazu; Yasue, Akihiro; Matsuhisa, Munehide; Noji, Sumihare; Fujimura, Tatsuya; Fuchimoto, Dai-Ichiro; Otoi, Takeshige

    2016-09-01

    Genetically modified pigs for biomedical applications have been mainly generated using the somatic cell nuclear transfer technique; however, this approach requires complex micromanipulation techniques and sometimes increases the risks of both prenatal and postnatal death by faulty epigenetic reprogramming of a donor somatic cell nucleus. As a result, the production of genetically modified pigs has not been widely applied. We provide a simple method for CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 gene editing in pigs that involves the introduction of Cas9 protein and single-guide RNA into in vitro fertilized zygotes by electroporation. The use of gene editing by electroporation of Cas9 protein (GEEP) resulted in highly efficient targeted gene disruption and was validated by the efficient production of Myostatin mutant pigs. Because GEEP does not require the complex methods associated with micromanipulation for somatic reprogramming, it has the potential for facilitating the genetic modification of pigs.

  14. Somatic cell reprogramming-free generation of genetically modified pigs

    PubMed Central

    Tanihara, Fuminori; Takemoto, Tatsuya; Kitagawa, Eri; Rao, Shengbin; Do, Lanh Thi Kim; Onishi, Akira; Yamashita, Yukiko; Kosugi, Chisato; Suzuki, Hitomi; Sembon, Shoichiro; Suzuki, Shunichi; Nakai, Michiko; Hashimoto, Masakazu; Yasue, Akihiro; Matsuhisa, Munehide; Noji, Sumihare; Fujimura, Tatsuya; Fuchimoto, Dai-ichiro; Otoi, Takeshige

    2016-01-01

    Genetically modified pigs for biomedical applications have been mainly generated using the somatic cell nuclear transfer technique; however, this approach requires complex micromanipulation techniques and sometimes increases the risks of both prenatal and postnatal death by faulty epigenetic reprogramming of a donor somatic cell nucleus. As a result, the production of genetically modified pigs has not been widely applied. We provide a simple method for CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 gene editing in pigs that involves the introduction of Cas9 protein and single-guide RNA into in vitro fertilized zygotes by electroporation. The use of gene editing by electroporation of Cas9 protein (GEEP) resulted in highly efficient targeted gene disruption and was validated by the efficient production of Myostatin mutant pigs. Because GEEP does not require the complex methods associated with micromanipulation for somatic reprogramming, it has the potential for facilitating the genetic modification of pigs. PMID:27652340

  15. MaizeGDB, the maize model organism database

    Technology Transfer Automated Retrieval System (TEKTRAN)

    MaizeGDB is the maize research community's database for maize genetic and genomic information. In this seminar I will outline our current endeavors including a full website redesign, the status of maize genome assembly and annotation projects, and work toward genome functional annotation. Mechanis...

  16. Genetically modified crops in a 10-generation feeding trial on Japanese quails--Evaluation of its influence on birds' performance and body composition.

    PubMed

    Sartowska, K E; Korwin-Kossakowska, A; Sender, G

    2015-12-01

    The effect of genetically modified (GM) feed components comprising soya bean meal and maize on the performance indices (reproduction, survival rate, growth, egg production, relative weight of chosen internal organs, and basic chemical composition of breast muscle and egg yolk) of Japanese quails was investigated during a 10-generation trial. A total number of 8,438 healthy quail chicks were used in the course of the trial. In each generation, birds were maintained in 3 experimental groups differing in the main feed components, i.e. 1) GM soya (Roundup Ready) and non-GM maize, 2) GM maize (MON810) and non-GM soya, and 3) non-GM soya and maize. The different feeds used did not influence any of the biological hatch indices, survival rate, or BW of young or adult quails. With regard to egg-laying performance, the GM maize group showed a better laying percentage and a higher egg mass production compared to the other groups; the GM soya group showed reduced average egg mass compared to the other groups, whereas the overall egg production level was the same as in the control group. Results showed a higher relative weight of breast muscle and gizzard in birds fed GM maize compared to the control group, whereas live BW and the relative weights of liver and heart were not different among groups. Meat from the GM soya group showed higher protein and lower fat levels compared to the control group. In the case of egg yolk, its chemical composition in the experimental groups did not differ from the control group. Even though some differences were found among the feeding groups, none could be judged as a negative influence of GM maize or GM soya in feed on the birds or final consumer products over 10 generations of Japanese quails.

  17. The maize milkweed pod1 mutant reveals a mechanism to modify organ morphology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A detailed examination of normal prophyll development indicates that polarity is established differently in the keels than in other parts of the prophyll. Analysis of the maize HD-ZIPIII gene rolled leaf1 (rld1) suggests that altered expression patterns are responsible for keel outgrowth. Recessive ...

  18. Genetically engineered plants, endangered species, and risk: a temporal and spatial exposure assessment for Karner blue butterfly larvae and Bt maize pollen.

    PubMed

    Peterson, Robert K D; Meyer, Steven J; Wolf, Amy T; Wolt, Jeffrey D; Davis, Paula M

    2006-06-01

    Genetically engineered maize (Zea mays) containing insecticidal endotoxin proteins from Bacillus thuringiensis (Bt) delta-endotoxin proteins has been adopted widely in the Midwestern United States. The proteins are toxic to several lepidopteran species and because a variety of maize tissues, including pollen, may express the endotoxins, the probability of exposure to nontarget species, including endangered species, needs to be understood. The objective of this study was to assess the potential temporal and spatial exposure of endangered Karner blue butterfly larvae (Lycaeides melissa samuelis) to Bt maize pollen in Wisconsin using probabilistic exposure techniques and geographic information systems analysis. Based on degree-day modeling of butterfly phenology and maize pollen shed, there is some potential for temporal exposure of larvae to maize pollen. However, in the majority of years and locations, maize pollen shed most likely will occur after the majority of larval feeding on wild lupine (Lupinus perennis). The spatial analysis indicates that some Karner blue butterfly populations occur in close proximity to maize fields, but in the vast majority of cases the butterfly's host plant and maize fields are separated by more than 500 m. A small number of potential or existing Karner blue butterfly sites are located near maize fields, including sites in two of the four counties where temporal overlap is most likely. The exposure assessment indicates that these two counties should receive the highest priority to determine if Karner blue butterfly larvae are actually at risk and then, if needed, to reduce or prevent exposure.

  19. HYBRIDIZATION STUDY BETWEEN GENETICALLY MODIFIED BRASSICA NAPUS AND NON-GENETICALLY MODIFIED B. NAPUS AND B. RAPA

    EPA Science Inventory

    Gene exchange between cultivated crops and wild species has gained significance in recent years because of concerns regarding the potential for gene flow between genetically modified (GM) crops and their domesticated and wild relatives. As part of our ecological effects of gene ...

  20. The Genetic Basis of Natural Variation in Kernel Size and Related Traits Using a Four-Way Cross Population in Maize.

    PubMed

    Chen, Jiafa; Zhang, Luyan; Liu, Songtao; Li, Zhimin; Huang, Rongrong; Li, Yongming; Cheng, Hongliang; Li, Xiantang; Zhou, Bo; Wu, Suowei; Chen, Wei; Wu, Jianyu; Ding, Junqiang

    2016-01-01

    Kernel size is an important component of grain yield in maize breeding programs. To extend the understanding on the genetic basis of kernel size traits (i.e., kernel length, kernel width and kernel thickness), we developed a set of four-way cross mapping population derived from four maize inbred lines with varied kernel sizes. In the present study, we investigated the genetic basis of natural variation in seed size and other components of maize yield (e.g., hundred kernel weight, number of rows per ear, number of kernels per row). In total, ten QTL affecting kernel size were identified, three of which (two for kernel length and one for kernel width) had stable expression in other components of maize yield. The possible genetic mechanism behind the trade-off of kernel size and yield components was discussed.

  1. Potential subchronic food safety of the stacked trait transgenic maize GH5112E-117C in Sprague-Dawley rats.

    PubMed

    Han, Shiwen; Zou, Shiying; He, Xiaoyun; Huang, Kunlun; Mei, Xiaohong

    2016-08-01

    The food safety of stacked trait genetically modified (GM) maize GH5112E-117C containing insect-resistance gene Cry1Ah and glyphosate-resistant gene G2-aroA was evaluated in comparison to non-GM Hi-II maize fed to Sprague-Dawley rats during a 90-day subchronic feeding study. Three different dietary concentrations (12.5, 25 and 50 %, w/w) of the GM maize were used or its corresponding non-GM maize. No biologically significant differences in the animals' clinical signs, body weights, food consumption, hematology, clinical chemistry, organ weights and histopathology were found between the stacked trait GM maize groups, and the non-GM maize groups. The results of the 90-day subchronic feeding study demonstrated that the stacked trait GM maize GH5112E-117C is as safe as the conventional non-GM maize Hi-II.

  2. Detecting un-authorized genetically modified organisms (GMOs) and derived materials.

    PubMed

    Holst-Jensen, Arne; Bertheau, Yves; de Loose, Marc; Grohmann, Lutz; Hamels, Sandrine; Hougs, Lotte; Morisset, Dany; Pecoraro, Sven; Pla, Maria; Van den Bulcke, Marc; Wulff, Doerte

    2012-01-01

    Genetically modified plants, in the following referred to as genetically modified organisms or GMOs, have been commercially grown for almost two decades. In 2010 approximately 10% of the total global crop acreage was planted with GMOs (James, 2011). More than 30 countries have been growing commercial GMOs, and many more have performed field trials. Although the majority of commercial GMOs both in terms of acreage and specific events belong to the four species: soybean, maize, cotton and rapeseed, there are another 20+ species where GMOs are commercialized or in the pipeline for commercialization. The number of GMOs cultivated in field trials or for commercial production has constantly increased during this time period. So have the number of species, the number of countries involved, the diversity of novel (added) genetic elements and the global trade. All of these factors contribute to the increasing complexity of detecting and correctly identifying GMO derived material. Many jurisdictions, including the European Union (EU), legally distinguish between authorized (and therefore legal) and un-authorized (and therefore illegal) GMOs. Information about the developments, field trials, authorizations, cultivation, trade and observations made in the official GMO control laboratories in different countries around the world is often limited, despite several attempts such as the OECD BioTrack for voluntary dissemination of data. This lack of information inevitably makes it challenging to detect and identify GMOs, especially the un-authorized GMOs. The present paper reviews the state of the art technologies and approaches in light of coverage, practicability, sensitivity and limitations. Emphasis is put on exemplifying practical detection of un-authorized GMOs. Although this paper has a European (EU) bias when examples are given, the contents have global relevance.

  3. Genetic, evolutionary and plant breeding insights from the domestication of maize

    PubMed Central

    Hake, Sarah; Ross-Ibarra, Jeffrey

    2015-01-01

    The natural history of maize began nine thousand years ago when Mexican farmers started to collect the seeds of the wild grass, teosinte. Invaluable as a food source, maize permeated Mexican culture and religion. Its domestication eventually led to its adoption as a model organism, aided in large part by its large chromosomes, ease of pollination and growing agricultural importance. Genome comparisons between varieties of maize, teosinte and other grasses are beginning to identify the genes responsible for the domestication of modern maize and are also providing ideas for the breeding of more hardy varieties. DOI: http://dx.doi.org/10.7554/eLife.05861.001 PMID:25807085

  4. Evaluation of Hbr (MITE) markers for assessment of genetic relationships among maize ( Zea mays L.) inbred lines.

    PubMed

    Casa, A M; Mitchell, S E; Smith, O S; Register, J C; Wessler, S R; Kresovich, S

    2002-01-01

    Recently, a new type of molecular marker has been developed that is based on the presence or absence of the miniature inverted repeat transposable element (MITE) family Heartbreaker ( Hbr) in the maize genome. These so-called Hbr markers have been shown to be stable, highly polymorphic, easily mapped, and evenly distributed throughout the maize genome. In this work, we used Hbr-derived markers for genetic characterization of a set of maize inbred lines belonging to Stiff Stalk (SS) and Non-Stiff Stalk (NSS) heterotic groups. In total, 111 markers were evaluated across 62 SS and NSS lines. Seventy six markers (68%) were shared between the two groups, and 25 of the common markers occurred at fairly low frequency (maize inbred lines.

  5. Assessment of testcross performance and genetic diversity of yellow endosperm maize lines derived from adapted x exotic backcrosses.

    PubMed

    Menkir, A; Olowolafe, M O; Ingelbrecht, I; Fawole, I; Badu-Apraku, B; Vroh, B I

    2006-06-01

    Introduction of exotic maize (Zea mays L.) into adapted tropical germplasm may enhance genetic variability and lead to greater progress from selection. The first objective of this study was to determine if yellow endosperm lines derived from adapted x exotic backcrosses contain exotic alleles that are superior to the recurrent adapted parental line for yield and other agronomic traits in tropical environments. Thirteen exotic yellow maize inbred lines were crossed to an adapted orange line (KUSR) and the F1s were backcrossed to KUSR to generate the first backcrosses. Fifty BC1F4 lines derived from these backcrosses and the recurrent parent were crossed to a common inbred tester (L4001) to form testcrosses, which were evaluated at eight environments in Nigeria. Testcrosses of the BC-derived lines differed significantly for grain yield and other agronomic traits. Only two testcrosses yielded significantly less than L4001 x KUSR, with the best 15 testcrosses producing between 289 and 1,056 kg/ha more grain yield than L4001 x KUSR. The best testcrosses were similar to or better than L4001 x KUSR for other agronomic traits. The second objective of this study was to assess the extent of genetic diversity present among the BC-derived lines. We genotyped 46 BC-derived lines including KUSR and L4001 with 10 AFLP primer pairs and found 491 polymorphic fragments. The average allelic diversity of the lines was 0.30 +/- 0.01. The genetic distance of each BC-derived line from KUSR ranged between 0.49 and 0.91. The average genetic distance for all pairs of the BC-derived lines was 0.68 +/- 0.004, varying from 0.34 to 0.92. The increased grain yield and genetic diversity observed in these studies provide evidence that exotic germplasm can contribute new alleles to expand the genetic base of tropical maize and develop high-yielding hybrids.

  6. The relationship between parental genetic or phenotypic divergence and progeny variation in the maize nested association mapping population

    PubMed Central

    Hung, H-Y; Browne, C; Guill, K; Coles, N; Eller, M; Garcia, A; Lepak, N; Melia-Hancock, S; Oropeza-Rosas, M; Salvo, S; Upadyayula, N; Buckler, E S; Flint-Garcia, S; McMullen, M D; Rocheford, T R; Holland, J B

    2012-01-01

    Appropriate selection of parents for the development of mapping populations is pivotal to maximizing the power of quantitative trait loci detection. Trait genotypic variation within a family is indicative of the family's informativeness for genetic studies. Accurate prediction of the most useful parental combinations within a species would help guide quantitative genetics studies. We tested the reliability of genotypic and phenotypic distance estimators between pairs of maize inbred lines to predict genotypic variation for quantitative traits within families derived from biparental crosses. We developed 25 families composed of ∼200 random recombinant inbred lines each from crosses between a common reference parent inbred, B73, and 25 diverse maize inbreds. Parents and families were evaluated for 19 quantitative traits across up to 11 environments. Genetic distances (GDs) among parents were estimated with 44 simple sequence repeat and 2303 single-nucleotide polymorphism markers. GDs among parents had no predictive value for progeny variation, which is most likely due to the choice of neutral markers. In contrast, we observed for about half of the traits measured a positive correlation between phenotypic parental distances and within-family genetic variance estimates. Consequently, the choice of promising segregating populations can be based on selecting phenotypically diverse parents. These results are congruent with models of genetic architecture that posit numerous genes affecting quantitative traits, each segregating for allelic series, with dispersal of allelic effects across diverse genetic material. This architecture, common to many quantitative traits in maize, limits the predictive value of parental genotypic or phenotypic values on progeny variance. PMID:22027895

  7. Genotyping and phenotyping of an epigenetic modifier Unstable factor for orange1 (Ufo1) in maize

    NASA Astrophysics Data System (ADS)

    Bowersox, Karisa; Chopra, Surinder

    2012-02-01

    Pericarp color 1 is a model system for the study of epigenetic gene regulation. It has more than 100 alleles that contribute to the color of the pericarp and cob glume of maize. Unstable factor for orange 1 (Ufo1) is a spontaneous dominant mutation that leads to a gain in pigmentation due to a decrease in methylation in p1 genes. This decrease in methylation of cytosine in the DNA leads to changes in chromatin structure. Finding the mechanism for this spontaneous mutation can lead to way of preventing the mutation increasing production colorless maize for food production. Through genotyping and phenotyping fine gene mapping, gene expression and whole genome profiling can be accomplished for plants with the Ufo1 mutation present.

  8. Relationship of the channels of normal maize starch to the properties of its modified products.

    PubMed

    Sui, Zhongquan; BeMiller, James N

    2013-01-30

    Starches from 5 inbred lines of normal maize with different relative average degrees of channelization (RADC) that could be divided into two groups (2 with RADC values of 1.49-1.52 and 3 with RADC values of 0.10-0.17) were reacted with 4 highly reactive reagents. No consistent correlations between RADC and the effects of derivatization with the 4 reagents on physical properties, either without or after surface protein removal, were found. Reaction with propylene oxide, a slowly reacting reagent whose reaction should be independent of RADC, resulted in an inverse relationship between several physical properties and RADC. The results indicate that there are inherent granular and molecular differences in the maize starches that control reactivity that are more influential than RADC (at least with the degrees of modification used), that the differences carry through chemical derivatization, and that different reagents react differently with different starches.

  9. Evaluation of plasmid and genomic DNA calibrants used for the quantification of genetically modified organisms.

    PubMed

    Caprioara-Buda, M; Meyer, W; Jeynov, B; Corbisier, P; Trapmann, S; Emons, H

    2012-07-01

    The reliable quantification of genetically modified organisms (GMOs) by real-time PCR requires, besides thoroughly validated quantitative detection methods, sustainable calibration systems. The latter establishes the anchor points for the measured value and the measurement unit, respectively. In this paper, the suitability of two types of DNA calibrants, i.e. plasmid DNA and genomic DNA extracted from plant leaves, for the certification of the GMO content in reference materials as copy number ratio between two targeted DNA sequences was investigated. The PCR efficiencies and coefficients of determination of the calibration curves as well as the measured copy number ratios for three powder certified reference materials (CRMs), namely ERM-BF415e (NK603 maize), ERM-BF425c (356043 soya), and ERM-BF427c (98140 maize), originally certified for their mass fraction of GMO, were compared for both types of calibrants. In all three systems investigated, the PCR efficiencies of plasmid DNA were slightly closer to the PCR efficiencies observed for the genomic DNA extracted from seed powders rather than those of the genomic DNA extracted from leaves. Although the mean DNA copy number ratios for each CRM overlapped within their uncertainties, the DNA copy number ratios were significantly different using the two types of calibrants. Based on these observations, both plasmid and leaf genomic DNA calibrants would be technically suitable as anchor points for the calibration of the real-time PCR methods applied in this study. However, the most suitable approach to establish a sustainable traceability chain is to fix a reference system based on plasmid DNA.

  10. Copy number ratios determined by two digital polymerase chain reaction systems in genetically modified grains

    NASA Astrophysics Data System (ADS)

    Pérez Urquiza, M.; Acatzi Silva, A. I.

    2014-02-01

    Three certified reference materials produced from powdered seeds to measure the copy number ratio sequences of p35S/hmgA in maize containing MON 810 event, p35S/Le1 in soybeans containing GTS 40-3-2 event and DREB1A/acc1 in wheat were produced according to the ISO Guides 34 and 35. In this paper, we report digital polymerase chain reaction (dPCR) protocols, performance parameters and results of copy number ratio content of genetically modified organisms (GMOs) in these materials using two new dPCR systems to detect and quantify molecular deoxyribonucleic acid: the BioMark® (Fluidigm) and the OpenArray® (Life Technologies) systems. These technologies were implemented at the National Institute of Metrology in Mexico (CENAM) and in the Reference Center for GMO Detection from the Ministry of Agriculture (CNRDOGM), respectively. The main advantage of this technique against the more-used quantitative polymerase chain reaction (qPCR) is that it generates an absolute number of target molecules in the sample, without reference to standards or an endogenous control, which is very useful when not much information is available for new developments or there are no standard reference materials in the market as in the wheat case presented, or when it was not possible to test the purity of seeds as in the maize case presented here. Both systems reported enhanced productivity, increased reliability and reduced instrument footprint. In this paper, the performance parameters and uncertainty of measurement obtained with both systems are presented and compared.

  11. Outcrossing potential between 11 important genetically modified crops and the Chilean vascular flora.

    PubMed

    Sánchez, Miguel A; Cid, Pablo; Navarrete, Humberto; Aguirre, Carlos; Chacón, Gustavo; Salazar, Erika; Prieto, Humberto

    2016-02-01

    The potential impact of genetically modified (GM) crops on biodiversity is one of the main concerns in an environmental risk assessment (ERA). The likelihood of outcrossing and pollen-mediated gene flow from GM crops and non-GM crops are explained by the same principles and depend primarily on the biology of the species. We conducted a national-scale study of the likelihood of outcrossing between 11 GM crops and vascular plants in Chile by use of a systematized database that included cultivated, introduced and native plant species in Chile. The database included geographical distributions and key biological and agronomical characteristics for 3505 introduced, 4993 native and 257 cultivated (of which 11 were native and 246 were introduced) plant species. Out of the considered GM crops (cotton, soya bean, maize, grape, wheat, rice, sugar beet, alfalfa, canola, tomato and potato), only potato and tomato presented native relatives (66 species total). Introduced relative species showed that three GM groups were formed having: a) up to one introduced relative (cotton and soya bean), b) up to two (rice, grape, maize and wheat) and c) from two to seven (sugar beet, alfalfa, canola, tomato and potato). In particular, GM crops presenting introduced noncultivated relative species were canola (1 relative species), alfalfa (up to 4), rice (1), tomato (up to 2) and potato (up to 2). The outcrossing potential between species [OP; scaled from 'very low' (1) to 'very high' (5)] was developed, showing medium OPs (3) for GM-native relative interactions when they occurred, low (2) for GMs and introduced noncultivated and high (4) for the grape-Vitis vinifera GM-introduced cultivated interaction. This analytical tool might be useful for future ERA for unconfined GM crop release in Chile.

  12. A literature review on the safety assessment of genetically modified plants.

    PubMed

    Domingo, José L; Giné Bordonaba, Jordi

    2011-05-01

    In recent years, there has been a notable concern on the safety of genetically modified (GM) foods/plants, an important and complex area of research, which demands rigorous standards. Diverse groups including consumers and environmental Non Governmental Organizations (NGO) have suggested that all GM foods/plants should be subjected to long-term animal feeding studies before approval for human consumption. In 2000 and 2006, we reviewed the information published in international scientific journals, noting that the number of references concerning human and animal toxicological/health risks studies on GM foods/plants was very limited. The main goal of the present review was to assess the current state-of-the-art regarding the potential adverse effects/safety assessment of GM plants for human consumption. The number of citations found in databases (PubMed and Scopus) has dramatically increased since 2006. However, new information on products such as potatoes, cucumber, peas or tomatoes, among others was not available. Corn/maize, rice, and soybeans were included in the present review. An equilibrium in the number research groups suggesting, on the basis of their studies, that a number of varieties of GM products (mainly maize and soybeans) are as safe and nutritious as the respective conventional non-GM plant, and those raising still serious concerns, was currently observed. Nevertheless, it should be noted that most of these studies have been conducted by biotechnology companies responsible of commercializing these GM plants. These findings suggest a notable advance in comparison with the lack of studies published in recent years in scientific journals by those companies. All this recent information is herein critically reviewed.

  13. Discrimination of genetically modified sugar beets based on terahertz spectroscopy.

    PubMed

    Chen, Tao; Li, Zhi; Yin, Xianhua; Hu, Fangrong; Hu, Cong

    2016-01-15

    The objective of this paper was to apply terahertz (THz) spectroscopy combined with chemometrics techniques for discrimination of genetically modified (GM) and non-GM sugar beets. In this paper, the THz spectra of 84 sugar beet samples (36 GM sugar beets and 48 non-GM ones) were obtained by using terahertz time-domain spectroscopy (THz-TDS) system in the frequency range from 0.2 to 1.2 THz. Three chemometrics methods, principal component analysis (PCA), discriminant analysis (DA) and discriminant partial least squares (DPLS), were employed to classify sugar beet samples into two groups: genetically modified organisms (GMOs) and non-GMOs. The DPLS method yielded the best classification result, and the percentages of successful classification for GM and non-GM sugar beets were both 100%. Results of the present study demonstrate the usefulness of THz spectroscopy together with chemometrics methods as a powerful tool to distinguish GM and non-GM sugar beets.

  14. Discrimination of genetically modified sugar beets based on terahertz spectroscopy

    NASA Astrophysics Data System (ADS)

    Chen, Tao; Li, Zhi; Yin, Xianhua; Hu, Fangrong; Hu, Cong

    2016-01-01

    The objective of this paper was to apply terahertz (THz) spectroscopy combined with chemometrics techniques for discrimination of genetically modified (GM) and non-GM sugar beets. In this paper, the THz spectra of 84 sugar beet samples (36 GM sugar beets and 48 non-GM ones) were obtained by using terahertz time-domain spectroscopy (THz-TDS) system in the frequency range from 0.2 to 1.2 THz. Three chemometrics methods, principal component analysis (PCA), discriminant analysis (DA) and discriminant partial least squares (DPLS), were employed to classify sugar beet samples into two groups: genetically modified organisms (GMOs) and non-GMOs. The DPLS method yielded the best classification result, and the percentages of successful classification for GM and non-GM sugar beets were both 100%. Results of the present study demonstrate the usefulness of THz spectroscopy together with chemometrics methods as a powerful tool to distinguish GM and non-GM sugar beets.

  15. Genetically modified foods: hazard identification and risk assessment. Session summary.

    PubMed

    Ito, Nobuyuki

    2002-07-01

    During a Joint Society of Toxicologic Pathology (STP)/International Federation of Societies of Toxicologic Pathologists (IFSTP) International Symposium, held between June 24 and 28, 2001, in Orlando, FL, USA, there was a session entitled as "Genetically Modified Foods: Hazard Identification and Risk Assessment". The purpose of this session was to present and discuss the current situations in the US, European Union and Japan for the public concerns, safety assessments and regulations on genetically modified (GM) products used as foods or food ingredients. Assuming the wide and fast growing of the usage of GM products, it is the duty for us as toxicologic pathologists, to supply reliable data on their safety and possible risks or hazards as a world-wide basis to not only governments or regulatory agencies but also general public of our countries.

  16. Detection of genetically modified organisms by electrochemiluminescence PCR method.

    PubMed

    Liu, Jinfeng; Xing, Da; Shen, Xingyan; Zhu, Debin

    2004-10-15

    With the development of biotechnology, more and more genetically modified organisms (GMOs) have entered commercial market. Because of the safety concerns, detection and characterization of GMOs have attracted much attention recently. In this study, electrochemiluminescence polymerase chain reaction (ECL-PCR) combined with hybridization technique was applied to detect the GMOs in genetically modified (GM) soybeans and papayas for the first time. Whether the soybeans and the papayas contain GM components was discriminated by detecting the Cauliflower mosaic virus 35S (CaMV35S) promoter. The experiment results show that the detection limit for CaMV35S promoter is 100 fmol, and the GM components can be clearly identified in GM soybeans and papayas. The technique may provide a new means in GMOs detection due to its simplicity and high efficiency.

  17. Application of genetically modified and cloned pigs in translational research.

    PubMed

    Matsunari, Hitomi; Nagashima, Hiroshi

    2009-06-01

    Pigs are increasingly being recognized as good large-animal models for translational research, linking basic science to clinical applications in order to establish novel therapeutics. This article reviews the current status and future prospects of genetically modified and cloned pigs in translational studies. It also highlights pigs specially designed as disease models, for xenotransplantation or to carry cell marker genes. Finally, use of porcine somatic stem and progenitor cells in preclinical studies of cell transplantation therapy is also discussed.

  18. How can genetically modified foods be made publicly acceptable?

    PubMed

    Rowe, Gene

    2004-03-01

    A recent study by Lusk suggests that consumers might voluntarily pay more for a genetically modified (GM) food than a non-GM equivalent if made aware of the possible health benefits. However, other research indicates that the acceptability of novel hazards is affected by a variety of factors, in addition to benefits, and that making agricultural biotechnology publicly acceptable will be more complex than indicated by the results from Lusk's study.

  19. Exploitation of genetically modified inoculants for industrial ecology applications.

    PubMed

    Morrissey, John P; Walsh, Ultan F; O'Donnell, Anne; Moënne-Loccoz, Yvan; O'Gara, Fergal

    2002-08-01

    The major growth seen in the biotechnology industry in recent decades has largely been driven by the exploitation of genetic engineering techniques. The initial benefits have been predominantly in the biomedical area, with products such as vaccines and hormones that have received broad public approval. In the environmental biotechnology and industrial ecology sectors, biotechnology has the potential to make significant advances through the use of genetically modified (GM) microbial inoculants that can reduce agri-chemical usage or remediate polluted environments. Although many GM inoculants have been developed and tested under laboratory conditions, commercial exploitation has lagged behind. Here, we review scientific and regulatory requirements that must be satisfied as part of that exploitation process. Particular attention is paid to new European Union (EU) regulations (Directives) that govern the testing and release of genetically modified organisms and microbial plant protection inoculants in the EU. With regard to the release of GM inoculants, the impact of the inoculant and the fate of modified genes are important concerns. Long term monitoring of release sites is necessary to address these issues. Data are reported from the monitoring of a site 6 years after release of GM Sinorhizobium meliloti strains. It was found that despite the absence of a host plant, the GM strains persisted in the soil for at least 6 years. Horizontal transfer and microevolution of a GM plasmid between S. meliloti strains was also observed. These data illustrate the importance of assessing the long-term persistence of GM inoculants.

  20. Genetically modified T cells in cancer therapy: opportunities and challenges.

    PubMed

    Sharpe, Michaela; Mount, Natalie

    2015-04-01

    Tumours use many strategies to evade the host immune response, including downregulation or weak immunogenicity of target antigens and creation of an immune-suppressive tumour environment. T cells play a key role in cell-mediated immunity and, recently, strategies to genetically modify T cells either through altering the specificity of the T cell receptor (TCR) or through introducing antibody-like recognition in chimeric antigen receptors (CARs) have made substantial advances. The potential of these approaches has been demonstrated in particular by the successful use of genetically modified T cells to treat B cell haematological malignancies in clinical trials. This clinical success is reflected in the growing number of strategic partnerships in this area that have attracted a high level of investment and involve large pharmaceutical organisations. Although our understanding of the factors that influence the safety and efficacy of these therapies has increased, challenges for bringing genetically modified T-cell immunotherapy to many patients with different tumour types remain. These challenges range from the selection of antigen targets and dealing with regulatory and safety issues to successfully navigating the routes to commercial development. However, the encouraging clinical data, the progress in the scientific understanding of tumour immunology and the improvements in the manufacture of cell products are all advancing the clinical translation of these important cellular immunotherapies.

  1. Controversy over genetically modified organisms: the governing laws and regulations.

    PubMed

    Keatley, K L

    2000-01-01

    Genetically Modified Organisms (GMOs) are increasingly becoming a topic of controversy in the U.S. and abroad. The public is questioning their safety and wanting the products labeled as genetically modified. There are other concerns from some of the scientific world and some government officials and organizations such as the Food & Agricultural Organization (FAO) that question whether adequate research has been done to qualify GMOs as safe for long-term use. Of particular concern are the allergenic properties, a GMO may impart, possible transfer effects of antibiotic resistance (given that antibiotic resistant marker genes are used for many GMOs), the expression of previously unexpressed traits, and the drift of pollen from genetically modified crops. It has also been noted that the laws and regulations governing the biotechnology world are outdated, are not comprehensive, and span too many agencies. The primary agencies currently regulating biotechnology are the U.S. Department of Agriculture (USDA), the Food and Drug Administration (FDA), and the Environmental Protection Agency (EPA).

  2. Genetic regulation of cold-induced albinism in the maize inbred line A661

    PubMed Central

    Rodríguez, Víctor M.; Velasco, Pablo; Garrido, José L.; Revilla, Pedro; Ordás, Amando; Butrón, Ana

    2013-01-01

    In spite of multiple studies elucidating the regulatory pathways controlling chlorophyll biosynthesis and photosynthetic activity, little is known about the molecular mechanism regulating cold-induced chlorosis in higher plants. Herein the characterization of the maize inbred line A661 which shows a cold-induced albino phenotype is reported. The data show that exposure of seedlings to low temperatures during early leaf biogenesis led to chlorophyll losses in this inbred. A661 shows a high plasticity, recovering resting levels of photosynthesis activity when exposed to optimal temperatures. Biochemical and transcriptome data indicate that at suboptimal temperatures chlorophyll could not be fully accommodated in the photosynthetic antenna in A661, remaining free in the chloroplast. The accumulation of free chlorophyll activates the expression of an early light inducible protein (elip) gene which binds chlorophyll to avoid cross-reactions that could lead to the generation of harmful reactive oxygen species. Higher levels of the elip transcript were observed in plants showing a cold-induced albino phenotype. Forward genetic analysis reveals that a gene located on the short arm of chromosome 2 regulates this protective mechanism. PMID:23881393

  3. Genetic regulation of cold-induced albinism in the maize inbred line A661.

    PubMed

    Rodríguez, Víctor M; Velasco, Pablo; Garrido, José L; Revilla, Pedro; Ordás, Amando; Butrón, Ana

    2013-09-01

    In spite of multiple studies elucidating the regulatory pathways controlling chlorophyll biosynthesis and photosynthetic activity, little is known about the molecular mechanism regulating cold-induced chlorosis in higher plants. Herein the characterization of the maize inbred line A661 which shows a cold-induced albino phenotype is reported. The data show that exposure of seedlings to low temperatures during early leaf biogenesis led to chlorophyll losses in this inbred. A661 shows a high plasticity, recovering resting levels of photosynthesis activity when exposed to optimal temperatures. Biochemical and transcriptome data indicate that at suboptimal temperatures chlorophyll could not be fully accommodated in the photosynthetic antenna in A661, remaining free in the chloroplast. The accumulation of free chlorophyll activates the expression of an early light inducible protein (elip) gene which binds chlorophyll to avoid cross-reactions that could lead to the generation of harmful reactive oxygen species. Higher levels of the elip transcript were observed in plants showing a cold-induced albino phenotype. Forward genetic analysis reveals that a gene located on the short arm of chromosome 2 regulates this protective mechanism.

  4. Phenotypic, genetic and molecular characterization of a maize low phytic acid mutant (lpa241).

    PubMed

    Pilu, R; Panzeri, D; Gavazzi, G; Rasmussen, S K; Consonni, G; Nielsen, E

    2003-10-01

    Phytic acid, myo-inositol 1,2,3,4,5,6-hexakisphosphate, is the major storage compound of phosphorous (P) in plants, predominantly accumulating in seeds (up to 4-5% of dry weight) and pollen. In cereals, phytic acid is deposited in embryo and aleurone grain tissues as a mixed "phytate" salt of potassium and magnesium, although phytates contain other mineral cations such as iron and zinc. During germination, phytates are broken down by the action of phytases, releasing their P, minerals and myo-inositol which become available to the growing seedling. Phytic acid represents an anti-nutritional factor for animals, and isolation of maize low phytic acid ( lpa) mutants provides a novel approach to study its biochemical pathway and to tackle the nutritional problems associated with it. Following chemical mutagenesis of pollen, we have isolated a viable recessive mutant named lpa 241 showing about 90% reduction of phytic acid and about a tenfold increase in seed-free phosphate content. Although germination rate was decreased by about 30% compared to wild-type, developement of mutant plants was apparentely unaffected. The results of the genetic, biochemical and molecular characterization experiments carried out by SSR mapping, MDD-HPLC and RT-PCR are consistent with a mutation affecting the MIPS1S gene, coding for the first enzyme of the phytic acid biosynthetic pathway.

  5. The Case of the "Tainted" Taco Shells: A Case Study on Genetically Modified Foods

    ERIC Educational Resources Information Center

    Taylor, Ann T. S.

    2004-01-01

    This case study introduces students to the use of genetically modified foods. Students learn how genetically modified plants are made, and then they read primary literature papers to evaluate the environmental, economic, and health issues. (Contains 2 figures.)

  6. Relationship between genetic parameters in maize (Zea mays) with seedling growth parameters under 40-100% soil moisture conditions.

    PubMed

    Muhammad, R W; Qayyum, A

    2013-10-18

    We estimated the association of genetic parameters with production characters in 64 maize (Zea mays) genotypes in a green house in soil with 40-100% moisture levels (percent of soil moisture capacity). To identify the major parameters that account for variation among the genotypes, we used single linkage cluster analysis and principle component analysis. Ten plant characters were measured. The first two, four, three, and again three components, with eigen values > 1 contributed 75.05, 80.11, 68.67, and 75.87% of the variability among the genotypes under the different moisture levels, i.e., 40, 60, 80, and 100%, respectively. Other principal components (3-10, 5-10, and 4-10) had eigen values less than 1. The highest estimates of heritability were found for root fresh weight, root volume (0.99), and shoot fresh weight (0.995) in 40% soil moisture. Values of genetic advance ranged from 23.4024 for SR at 40% soil moisture to 0.2538 for shoot dry weight in 60% soil moisture. The high magnitude of broad sense heritability provides evidence that these plant characters are under the control of additive genetic effects. This indicates that selection should lead to fast genetic improvement of the material. The superior agronomic types that we identified may be exploited for genetic potential to improve yield potential of the maize crop.

  7. One simple DNA extraction device and its combination with modified visual loop-mediated isothermal amplification for rapid on-field detection of genetically modified organisms.

    PubMed

    Zhang, Miao; Liu, Yinan; Chen, Lili; Quan, Sheng; Jiang, Shimeng; Zhang, Dabing; Yang, Litao

    2013-01-02

    Quickness, simplicity, and effectiveness are the three major criteria for establishing a good molecular diagnosis method in many fields. Herein we report a novel detection system for genetically modified organisms (GMOs), which can be utilized to perform both on-field quick screening and routine laboratory diagnosis. In this system, a newly designed inexpensive DNA extraction device was used in combination with a modified visual loop-mediated isothermal amplification (vLAMP) assay. The main parts of the DNA extraction device included a silica gel membrane filtration column and a modified syringe. The DNA extraction device could be easily operated without using other laboratory instruments, making it applicable to an on-field GMO test. High-quality genomic DNA (gDNA) suitable for polymerase chain reaction (PCR) and isothermal amplification could be quickly isolated from plant tissues using this device within 15 min. In the modified vLAMP assay, a microcrystalline wax encapsulated detection bead containing SYBR green fluorescent dye was introduced to avoid dye inhibition and cross-contaminations from post-LAMP operation. The system was successfully applied and validated in screening and identification of GM rice, soybean, and maize samples collected from both field testing and the Grain Inspection, Packers, and Stockyards Administration (GIPSA) proficiency test program, which demonstrated that it was well-adapted to both on-field testing and/or routine laboratory analysis of GMOs.

  8. Risk Assessment of Genetically Engineered Maize Resistant to Diabrotica spp.: Influence on Above-Ground Arthropods in the Czech Republic

    PubMed Central

    Svobodová, Zdeňka; Skoková Habuštová, Oxana; Hutchison, William D.; Hussein, Hany M.; Sehnal, František

    2015-01-01

    Transgenic maize MON88017, expressing the Cry3Bb1 toxin from Bacillus thuringiensis (Bt maize), confers resistance to corn rootworms (Diabrotica spp.) and provides tolerance to the herbicide glyphosate. However, prior to commercialization, substantial assessment of potential effects on non-target organisms within agroecosystems is required. The MON88017 event was therefore evaluated under field conditions in Southern Bohemia in 2009–2011, to detect possible impacts on the above-ground arthropod species. The study compared MON88017, its near-isogenic non-Bt hybrid DK315 (treated or not treated with the soil insecticide Dursban 10G) and two non-Bt reference hybrids (KIPOUS and PR38N86). Each hybrid was grown on five 0.5 ha plots distributed in a 14-ha field with a Latin square design. Semiquantitative ELISA was used to verify Cry3Bb1 toxin levels in the Bt maize. The species spectrum of non-target invertebrates changed during seasons and was affected by weather conditions. The thrips Frankliniella occidentalis was the most abundant species in all three successive years. The next most common species were aphids Rhopalosiphum padi and Metopolophium dirhodum. Frequently observed predators included Orius spp. and several species within the Coccinellidae. Throughout the three-year study, analysis of variance indicated some significant differences (P<0.05). Multivariate analysis showed that the abundance and diversity of plant dwelling insects was similar in maize with the same genetic background, for both Bt (MON88017) and non-Bt (DK315) untreated or insecticide treated. KIPOUS and PR38N86 showed some differences in species abundance relative to the Bt maize and its near-isogenic hybrid. However, the effect of management regime on arthropod community was insignificant and accounted only for a negligible portion of the variability. PMID:26083254

  9. Risk Assessment of Genetically Engineered Maize Resistant to Diabrotica spp.: Influence on Above-Ground Arthropods in the Czech Republic.

    PubMed

    Svobodová, Zdeňka; Skoková Habuštová, Oxana; Hutchison, William D; Hussein, Hany M; Sehnal, František

    2015-01-01

    Transgenic maize MON88017, expressing the Cry3Bb1 toxin from Bacillus thuringiensis (Bt maize), confers resistance to corn rootworms (Diabrotica spp.) and provides tolerance to the herbicide glyphosate. However, prior to commercialization, substantial assessment of potential effects on non-target organisms within agroecosystems is required. The MON88017 event was therefore evaluated under field conditions in Southern Bohemia in 2009-2011, to detect possible impacts on the above-ground arthropod species. The study compared MON88017, its near-isogenic non-Bt hybrid DK315 (treated or not treated with the soil insecticide Dursban 10G) and two non-Bt reference hybrids (KIPOUS and PR38N86). Each hybrid was grown on five 0.5 ha plots distributed in a 14-ha field with a Latin square design. Semiquantitative ELISA was used to verify Cry3Bb1 toxin levels in the Bt maize. The species spectrum of non-target invertebrates changed during seasons and was affected by weather conditions. The thrips Frankliniella occidentalis was the most abundant species in all three successive years. The next most common species were aphids Rhopalosiphum padi and Metopolophium dirhodum. Frequently observed predators included Orius spp. and several species within the Coccinellidae. Throughout the three-year study, analysis of variance indicated some significant differences (P<0.05). Multivariate analysis showed that the abundance and diversity of plant dwelling insects was similar in maize with the same genetic background, for both Bt (MON88017) and non-Bt (DK315) untreated or insecticide treated. KIPOUS and PR38N86 showed some differences in species abundance relative to the Bt maize and its near-isogenic hybrid. However, the effect of management regime on arthropod community was insignificant and accounted only for a negligible portion of the variability.

  10. Irradiation influence on the detection of genetic-modified soybeans

    NASA Astrophysics Data System (ADS)

    Villavicencio, A. L. C. H.; Araújo, M. M.; Baldasso, J. G.; Aquino, S.; Konietzny, U.; Greiner, R.

    2004-09-01

    Three soybean varieties were analyzed to evaluate the irradiation influence on the detection of genetic modification. Samples were treated in a 60Co facility at dose levels of 0, 500, 800, and 1000Gy. The seeds were at first analyzed by Comet Assay as a rapid screening irradiation detection method. Secondly, germination test was performed to detect the viability of irradiated soybeans. Finally, because of its high sensitivity, its specificity and rapidity the polimerase chain reaction was the method applied for genetic modified organism detection. The analysis of DNA by the single technique of microgel electrophoresis of single cells (DNA Comet Assay) showed that DNA damage increased with increasing radiation doses. No negative influence of irradiation on the genetic modification detection was found.

  11. Biocontainment of genetically modified organisms by synthetic protein design

    NASA Astrophysics Data System (ADS)

    Mandell, Daniel J.; Lajoie, Marc J.; Mee, Michael T.; Takeuchi, Ryo; Kuznetsov, Gleb; Norville, Julie E.; Gregg, Christopher J.; Stoddard, Barry L.; Church, George M.

    2015-02-01

    Genetically modified organisms (GMOs) are increasingly deployed at large scales and in open environments. Genetic biocontainment strategies are needed to prevent unintended proliferation of GMOs in natural ecosystems. Existing biocontainment methods are insufficient because they impose evolutionary pressure on the organism to eject the safeguard by spontaneous mutagenesis or horizontal gene transfer, or because they can be circumvented by environmentally available compounds. Here we computationally redesign essential enzymes in the first organism possessing an altered genetic code (Escherichia coli strain C321.ΔA) to confer metabolic dependence on non-standard amino acids for survival. The resulting GMOs cannot metabolically bypass their biocontainment mechanisms using known environmental compounds, and they exhibit unprecedented resistance to evolutionary escape through mutagenesis and horizontal gene transfer. This work provides a foundation for safer GMOs that are isolated from natural ecosystems by a reliance on synthetic metabolites.

  12. Biocontainment of genetically modified organisms by synthetic protein design.

    PubMed

    Mandell, Daniel J; Lajoie, Marc J; Mee, Michael T; Takeuchi, Ryo; Kuznetsov, Gleb; Norville, Julie E; Gregg, Christopher J; Stoddard, Barry L; Church, George M

    2015-02-05

    Genetically modified organisms (GMOs) are increasingly deployed at large scales and in open environments. Genetic biocontainment strategies are needed to prevent unintended proliferation of GMOs in natural ecosystems. Existing biocontainment methods are insufficient because they impose evolutionary pressure on the organism to eject the safeguard by spontaneous mutagenesis or horizontal gene transfer, or because they can be circumvented by environmentally available compounds. Here we computationally redesign essential enzymes in the first organism possessing an altered genetic code (Escherichia coli strain C321.ΔA) to confer metabolic dependence on non-standard amino acids for survival. The resulting GMOs cannot metabolically bypass their biocontainment mechanisms using known environmental compounds, and they exhibit unprecedented resistance to evolutionary escape through mutagenesis and horizontal gene transfer. This work provides a foundation for safer GMOs that are isolated from natural ecosystems by a reliance on synthetic metabolites.

  13. The Detection of Genetically Modified Organisms: An Overview

    NASA Astrophysics Data System (ADS)

    Ovesná, Jaroslava; Demnerová, Kateřina; Pouchová, Vladimíra

    Genetically modified organisms (GMOs) are those whose genetic material has been altered by the insertion of a new gene or by the deletion of an existing one(s). Modern biotechnology, in particular, the rise of genetic engineering, has supported the development of GMOs suitable for research purposes and practical applications (Gepts, 2002; Novoselova,Meuwissen, & Huirne, 2007; Sakakibara & Saito, 2006). For over 20 years GM bacteria and other GM organisms have been used in laboratories for the study of gene functions (Maliga & Small, 2007; Ratledge & Kristiansen, 2006). Agricultural plants were the first GMOs to be released into the environment and placed on the market. Farmers around the world use GMsoybeans, GMcorn and GM cotton that are herbicide tolerant, or insect resistant, or combine several traits that reduce the costs associated with crop production (Corinne, Fernandez-Cornejo, & Goodhue, 2004).

  14. Biocontainment of genetically modified organisms by synthetic protein design

    PubMed Central

    Mandell, Daniel J.; Lajoie, Marc J.; Mee, Michael T.; Takeuchi, Ryo; Kuznetsov, Gleb; Norville, Julie E.; Gregg, Christopher J.; Stoddard, Barry L.; Church, George M.

    2015-01-01

    Genetically modified organisms (GMOs) are increasingly deployed at large scales and in open environments. Genetic biocontainment strategies are needed to prevent unintended proliferation of GMOs in natural ecosystems. Existing biocontainment methods are insufficient either because they impose evolutionary pressure on the organism to eject the safeguard, because they can be circumvented by environmentally available compounds, or because they can be overcome by horizontal gene transfer (HGT). Here we computationally redesign essential enzymes in the first organism possessing an altered genetic code to confer metabolic dependence on nonstandard amino acids for survival. The resulting GMOs cannot metabolically circumvent their biocontainment mechanisms using environmentally available compounds, and they exhibit unprecedented resistance to evolutionary escape via mutagenesis and HGT. This work provides a foundation for safer GMOs that are isolated from natural ecosystems by reliance on synthetic metabolites. PMID:25607366

  15. Biocontainment of genetically modified organisms by synthetic protein design

    DOE PAGES

    Mandell, Daniel J.; Lajoie, Marc J.; Mee, Michael T.; ...

    2015-01-21

    Genetically modified organisms (GMOs) are increasingly deployed at large scales and in open environments. Genetic biocontainment strategies are needed to prevent unintended proliferation of GMOs in natural ecosystems. Existing biocontainment methods are insufficient because they impose evolutionary pressure on the organism to eject the safeguard by spontaneous mutagenesis or horizontal gene transfer, or because they can be circumvented by environmentally available compounds. In this paper, we computationally redesign essential enzymes in the first organism possessing an altered genetic code (Escherichia coli strain C321.ΔA) to confer metabolic dependence on non-standard amino acids for survival. The resulting GMOs cannot metabolically bypass theirmore » biocontainment mechanisms using known environmental compounds, and they exhibit unprecedented resistance to evolutionary escape through mutagenesis and horizontal gene transfer. Finally, this work provides a foundation for safer GMOs that are isolated from natural ecosystems by a reliance on synthetic metabolites.« less

  16. Biocontainment of genetically modified organisms by synthetic protein design

    SciTech Connect

    Mandell, Daniel J.; Lajoie, Marc J.; Mee, Michael T.; Takeuchi, Ryo; Kuznetsov, Gleb; Norville, Julie E.; Gregg, Christopher J.; Stoddard, Barry L.; Church, George M.

    2015-01-21

    Genetically modified organisms (GMOs) are increasingly deployed at large scales and in open environments. Genetic biocontainment strategies are needed to prevent unintended proliferation of GMOs in natural ecosystems. Existing biocontainment methods are insufficient because they impose evolutionary pressure on the organism to eject the safeguard by spontaneous mutagenesis or horizontal gene transfer, or because they can be circumvented by environmentally available compounds. In this paper, we computationally redesign essential enzymes in the first organism possessing an altered genetic code (Escherichia coli strain C321.ΔA) to confer metabolic dependence on non-standard amino acids for survival. The resulting GMOs cannot metabolically bypass their biocontainment mechanisms using known environmental compounds, and they exhibit unprecedented resistance to evolutionary escape through mutagenesis and horizontal gene transfer. Finally, this work provides a foundation for safer GMOs that are isolated from natural ecosystems by a reliance on synthetic metabolites.

  17. Genetically modified yeast species and fermentation processes using genetically modified yeast

    DOEpatents

    Rajgarhia, Vineet; Koivuranta, Kari; Penttila, Merja; Ilmen, Marja; Suominen, Pirkko; Aristidou, Aristos; Miller, Christopher Kenneth; Olson, Stacey; Ruohonen, Laura

    2011-05-17

    Yeast cells are transformed with an exogenous xylose isomerase gene. Additional genetic modifications enhance the ability of the transformed cells to ferment xylose to ethanol or other desired fermentation products. Those modifications', include deletion of non-specific or specific aldose reductase gene(s), deletion of xylitol dehydrogenase gene(s) and/or overexpression of xylulokinase.

  18. Genetically modified yeast species, and fermentation processes using genetically modified yeast

    SciTech Connect

    Rajgarhia, Vineet; Koivuranta, Kari; Penttila, Merja; Ilmen, Marja; Suominen, Pirkko; Aristidou, Aristos; Miller, Christopher Kenneth; Olson, Stacey; Ruohonen, Laura

    2014-01-07

    Yeast cells are transformed with an exogenous xylose isomerase gene. Additional genetic modifications enhance the ability of the transformed cells to ferment xylose to ethanol or other desired fermentation products. Those modifications include deletion of non-specific aldose reductase gene(s), deletion of xylitol dehydrogenase gene(s) and/or overexpression of xylulokinase.

  19. Genetically modified yeast species, and fermentation processes using genetically modified yeast

    SciTech Connect

    Rajgarhia, Vineet; Koivuranta, Kari; Penttila, Merja; Ilmen, Marja; Suominen, Pirkko; Aristidou, Aristos; Miller, Christopher Kenneth; Olson, Stacey; Ruohonen, Laura

    2013-05-14

    Yeast cells are transformed with an exogenous xylose isomerase gene. Additional genetic modifications enhance the ability of the transformed cells to ferment xylose to ethanol or other desired fermentation products. Those modifications include deletion of non-specific or specific aldose reductase gene(s), deletion of xylitol dehydrogenase gene(s) and/or overexpression of xylulokinase.

  20. Genetically modified yeast species, and fermentation processes using genetically modified yeast

    SciTech Connect

    Rajgarhia, Vineet; Koivuranta, Kari; Penttila, Merja; Ilmen, Marja; Suominen, Pirkko; Aristidou, Aristos; Miller, Christopher Kenneth; Olson, Stacey; Ruohonen, Laura

    2016-08-09

    Yeast cells are transformed with an exogenous xylose isomerase gene. Additional genetic modifications enhance the ability of the transformed cells to ferment xylose to ethanol or other desired fermentation products. Those modifications include deletion of non-specific or specific aldose reductase gene(s), deletion of xylitol dehydrogenase gene(s) and/or overexpression of xylulokinase.

  1. Genetic analysis and molecular mapping of maize (Zea mays L.) stalk rot resistant gene Rfg1.

    PubMed

    Yang, D E; Zhang, C L; Zhang, D S; Jin, D M; Weng, M L; Chen, S J; Nguyen, H; Wang, B

    2004-02-01

    One single pathogen Fusarium graminearum Schw. was inoculated to maize inbred lines 1,145 (Resistant) and Y331 (Susceptive), and their progenies of F(1), F(2) and BC(1)F(1) populations. Field statistical data revealed that all of the F(1) individuals were resistant to the disease and that the ratio of resistant plants to susceptive plants was 3:1 in the F(2) population, and 1:1 in the BC(1)F(1 )population. The results revealed that a single dominant gene controls the resistance to F. graminearum Schw. The resistant gene to F. graminearum Schw. was denominated as Rfg1 according to the standard principle of the nomenclature of the plant disease resistant genes. RAPD (randomly amplified polymorphic DNA) combined with BSA (bulked segregant analysis) analysis was carried out in the developed F(2) and BC(1)F(1 )populations, respectively. Three RAPD products screened from the RAPD analysis with 820 Operon 10-mer primers showed the linkage relation with the resistant gene Rfg1. The three RAPD amplification products (OPD-20(1000), OPA-04(1100) and OPY-04(900)) were cloned and their copy numbers were determined. The results indicated that only OPY-04(900) was a single-copy sequence. Then, OPY-04(900) was used as a probe to map the Rfg1 gene with a RIL F(7) mapping population provided by Henry Nguyen, which was developed from the cross "S3xMo17". Rfg1 was primarily mapped on chromosome 6 between the two linked markers OPY-04(900) and umc21 (Bin 6.04-6.05). In order to confirm the primary mapping result, 25 SSR (simple sequence repeat) markers and six RFLP (restriction fragment length polymorphism) markers in the Rfg1 gene-encompassing region were selected, and their linkage relation with Rfg1 was analyzed in our F(2) population. Results indicated that SSR marker mmc0241 and RFLP marker bnl3.03 are flanking the Rfg1 gene with a genetic distance of 3.0 cM and 2.0 cM, respectively. This is the first time to name and to map a single resistant gene of maize stalk rot through a

  2. Spatiotemporal patterns of non-genetically modified crops in the era of expansion of genetically modified food.

    PubMed

    Sun, Jing; Wu, Wenbin; Tang, Huajun; Liu, Jianguo

    2015-09-18

    Despite heated debates over the safety of genetically modified (GM) food, GM crops have been expanding rapidly. Much research has focused on the expansion of GM crops. However, the spatiotemporal dynamics of non-genetically modified (non-GM) crops are not clear, although they may have significant environmental and agronomic impacts and important policy implications. To understand the dynamics of non-GM crops and to inform the debates among relevant stakeholders, we conducted spatiotemporal analyses of China's major non-GM soybean production region, the Heilongjiang Province. Even though the total soybean planting area decreased from 2005 to 2010, surprisingly, there were hotspots of increase. The results also showed hotspots of loss as well as a large decline in the number and continuity of soybean plots. Since China is the largest non-GM soybean producer in the world, the decline of its major production region may signal the continual decline of global non-GM soybeans.

  3. Spatiotemporal patterns of non-genetically modified crops in the era of expansion of genetically modified food

    PubMed Central

    Sun, Jing; Wu, Wenbin; Tang, Huajun; Liu, Jianguo

    2015-01-01

    Despite heated debates over the safety of genetically modified (GM) food, GM crops have been expanding rapidly. Much research has focused on the expansion of GM crops. However, the spatiotemporal dynamics of non-genetically modified (non-GM) crops are not clear, although they may have significant environmental and agronomic impacts and important policy implications. To understand the dynamics of non-GM crops and to inform the debates among relevant stakeholders, we conducted spatiotemporal analyses of China’s major non-GM soybean production region, the Heilongjiang Province. Even though the total soybean planting area decreased from 2005 to 2010, surprisingly, there were hotspots of increase. The results also showed hotspots of loss as well as a large decline in the number and continuity of soybean plots. Since China is the largest non-GM soybean producer in the world, the decline of its major production region may signal the continual decline of global non-GM soybeans. PMID:26380899

  4. Molecular genetics of the R complex of maize. Final technical report DE-FG02-86ER13627

    SciTech Connect

    Dellaporta, Stephen

    2000-10-01

    A molecular genetic characterization of the maize R-r complex of maize was completed during the period of support. The complex was shown to consist of two main regions: the P region, containing the r-p gene which controlled pigmentation of plant parts, and the S subcomplex, containing two rl-s genes in head-to-head orientation and a nonfunctional component termed rl-q. By examining the DNA sequences at the junction of the rl genes, the complex was shown to be derived by a series of abortive transposition events. The transposable element involved in the gene duplication and rearrangements was characterized and called doppia. Meiotic instability of the R-r complex was also characterized. Loss of P or S function was associated with several structural changes including intrachromosomal recombination and excision of a novel transposable element that appears to show instability only during meiosis.

  5. Genetic and Quantitative Trait Locus Analysis for Bio-Oil Compounds after Fast Pyrolysis in Maize Cobs.

    PubMed

    Jeffrey, Brandon; Kuzhiyil, Najeeb; de Leon, Natalia; Lübberstedt, Thomas

    2016-01-01

    Fast pyrolysis has been identified as one of the biorenewable conversion platforms that could be a part of an alternative energy future, but it has not yet received the same attention as cellulosic ethanol in the analysis of genetic inheritance within potential feedstocks such as maize. Ten bio-oil compounds were measured via pyrolysis/gas chromatography-mass spectrometry (Py/GC-MS) in maize cobs. 184 recombinant inbred lines (RILs) of the intermated B73 x Mo17 (IBM) Syn4 population were analyzed in two environments, using 1339 markers, for quantitative trait locus (QTL) mapping. QTL mapping was performed using composite interval mapping with significance thresholds established by 1000 permutations at α = 0.05. 50 QTL were found in total across those ten traits with R2 values ranging from 1.7 to 5.8%, indicating a complex quantitative inheritance of these traits.

  6. Genetic and Quantitative Trait Locus Analysis for Bio-Oil Compounds after Fast Pyrolysis in Maize Cobs

    PubMed Central

    Jeffrey, Brandon; Kuzhiyil, Najeeb; de Leon, Natalia; Lübberstedt, Thomas

    2016-01-01

    Fast pyrolysis has been identified as one of the biorenewable conversion platforms that could be a part of an alternative energy future, but it has not yet received the same attention as cellulosic ethanol in the analysis of genetic inheritance within potential feedstocks such as maize. Ten bio-oil compounds were measured via pyrolysis/gas chromatography-mass spectrometry (Py/GC-MS) in maize cobs. 184 recombinant inbred lines (RILs) of the intermated B73 x Mo17 (IBM) Syn4 population were analyzed in two environments, using 1339 markers, for quantitative trait locus (QTL) mapping. QTL mapping was performed using composite interval mapping with significance thresholds established by 1000 permutations at α = 0.05. 50 QTL were found in total across those ten traits with R2 values ranging from 1.7 to 5.8%, indicating a complex quantitative inheritance of these traits. PMID:26745365

  7. Low phytic acid 1 mutation in maize modifies density, starch properties, cations, and fiber contents in the seed.

    PubMed

    Landoni, Michela; Cerino Badone, Francesco; Haman, Nabil; Schiraldi, Alberto; Fessas, Dimitrios; Cesari, Valentina; Toschi, Ivan; Cremona, Roberta; Delogu, Chiara; Villa, Daniela; Cassani, Elena; Pilu, Roberto

    2013-05-15

    Monogastric animals are unable to digest phytic acid, so it represents an antinutritional factor and also an environmental problem. One strategy to solve this problem is the utilization of low phytic acid (lpa) mutants that accumulate low levels of phytic P and high levels of free phosphate in the seeds; among the lpa maize mutants lpa1 exhibited the highest reduction of phytic acid in the seed. This study indicated that the low phytic acid mutations exerted pleiotropic effects not directly connected to the phytic acid pathway, such as on seed density, content of ions, and the antioxidant compounds present in the kernels. Furthermore some nutritional properties of the flour were altered by the lpa1 mutations, in particular lignin and protein content, while the starch does not seem to be modified as to the total amount and in the amylose/amylopectin ratio, but alterations were noticed in the structure and size of granules.

  8. Selection of focal earthworm species as non-target soil organisms for environmental risk assessment of genetically modified plants.

    PubMed

    van Capelle, Christine; Schrader, Stefan; Arpaia, Salvatore

    2016-04-01

    By means of a literature survey, earthworm species of significant relevance for soil functions in different biogeographical regions of Europe (Atlantic, Boreal, Mediterranean) were identified. These focal earthworm species, defined here according to the EFSA Guidance Document on the environmental risk assessment (ERA) of genetically modified plants, are typical for arable soils under crop rotations with maize and/or potatoes within the three regions represented by Ireland, Sweden and Spain, respectively. Focal earthworm species were selected following a matrix of four steps: Identification of functional groups, categorization of non-target species, ranking species on ecological criteria, and final selection of focal species. They are recommended as appropriate non-target organisms to assess environmental risks of genetically modified (GM) crops; in this case maize and potatoes. In total, 44 literature sources on earthworms in arable cropping systems including maize or potato from Ireland, Sweden and Spain were collected, which present information on species diversity, individual density and specific relevance for soil functions. By means of condensed literature data, those species were identified which (i) play an important functional role in respective soil systems, (ii) are well adapted to the biogeographical regions, (iii) are expected to occur in high abundances under cultivation of maize or potato and (iv) fulfill the requirements for an ERA test system based on life-history traits. First, primary and secondary decomposers were identified as functional groups being exposed to the GM crops. In a second step, anecic and endogeic species were categorized as potential species. In step three, eight anecic and endogeic earthworm species belonging to the family Lumbricidae were ranked as relevant species: Aporrectodea caliginosa, Aporrectodea rosea, Aporrectodea longa, Allolobophora chlorotica, Lumbricus terrestris, Lumbricus friendi, Octodrilus complanatus and

  9. Genetic and Molecular Characterization of Submergence Response Identifies Subtol6 as a Major Submergence Tolerance Locus in Maize

    PubMed Central

    Campbell, Malachy T.; Proctor, Christopher A.; Dou, Yongchao; Schmitz, Aaron J.; Phansak, Piyaporn; Kruger, Greg R.; Zhang, Chi; Walia, Harkamal

    2015-01-01

    Maize is highly sensitive to short term flooding and submergence. Early season flooding reduces germination, survival and growth rate of maize seedlings. We aimed to discover genetic variation for submergence tolerance in maize and elucidate the genetic basis of submergence tolerance through transcriptional profiling and linkage analysis of contrasting genotypes. A diverse set of maize nested association mapping (NAM) founder lines were screened, and two highly tolerant (Mo18W and M162W) and sensitive (B97 and B73) genotypes were identified. Tolerant lines exhibited delayed senescence and lower oxidative stress levels compared to sensitive lines. Transcriptome analysis was performed on these inbreds to provide genome level insights into the molecular responses to submergence. Tolerant lines had higher transcript abundance of several fermentation-related genes and an unannotated Pyrophosphate-Dependent Fructose-6-Phosphate 1-Phosphotransferase gene during submergence. A coexpression network enriched for CBF (C-REPEAT/DRE BINDING FACTOR: C-REPEAT/DRE BINDING FACTOR) genes, was induced by submergence in all four inbreds, but was more activated in the tolerant Mo18W. A recombinant inbred line (RIL) population derived from Mo18W and B73 was screened for submergence tolerance. A major QTL named Subtol6 was mapped to chromosome 6 that explains 22% of the phenotypic variation within the RIL population. We identified two candidate genes (HEMOGLOBIN2 and RAV1) underlying Subtol6 based on contrasting expression patterns observed in B73 and Mo18W. Sources of tolerance identified in this study (Subtol6) can be useful to increase survival rate during flooding events that are predicted to increase in frequency with climate change. PMID:25806518

  10. Maize authentication: quality control methods and multivariate analysis (chemometrics).

    PubMed

    Arvanitoyannis, Ioannis S; Vlachos, Antonios

    2009-06-01

    Maize is one of the most important cereals because of its numerous applications in processed foods where it is the major or minor component. Apart from maize authenticity issues related to cultivar and geographical origin (national and/or international level), there is another important issue related to genetically modified maize. Various objective parameters such as fatty acids, phenolic compounds, pigments, heavy metals were determined in conjunction with subjective (sensory analysis) in order to identify the maize authenticity. However, the implementation of multivariate analysis (principal component analysis, cluster analysis, discriminant analysis, canonical analysis) is of great importance toward reaching valid conclusions on authenticity issues. This review summarized the most important finding of both objective and subjective evaluations of maize in five comprehensive tables in conjunction with the discussion.

  11. Hypothetical link between infertility and genetically modified food.

    PubMed

    Gao, Mingxia; Li, Bin; Yuan, Wenzhen; Zhao, Lihui; Zhang, Xuehong

    2014-01-01

    It is speculated that genetically modified food (GMF)/genetically modified organism (GMO) is responsible for infertility development. The risk linked with a wide use of GMFs/GMOs offers the basic elements for social criticism. However, to date, it has not been justified whether the bad effects are directly resulted from products of genetic modifications or trans-genesis process. Extensive experience with the risk assessment of whole foods has been applied recently on the safety and nutritional testing of GMFs/GMOs. Investigations have tested the safety of GMFs including sub-acute, chronic, reproductive, multi-generation and carcinogenicity studies. We extrapolated the potential risks associated with GMFs/GMOs on reproduction, and analyzed the multi-aspect linked between infertility and GMFs/GMOs. It could be conjectured that GMFs/GMOs could be potential hazard on reproduction, linking to the development of infertility through influencing the endocrine metabolism, endometriosis. However, little evidence shows the impaction on embryo or reproductive related tumor due to the limited literatures, and needs further research. The article presents some related patents on GMFs/GMOs, and some methods for tracking GMOs.

  12. [Genetically modified organisms: a new threat to food safety].

    PubMed

    Spendeler, Liliane

    2005-01-01

    This article analyzes all of the food safety-related aspects related to the use of genetically modified organisms into agriculture and food. A discussion is provided as to the uncertainties related to the insertion of foreign genes into organisms, providing examples of unforeseen, undesirable effects and of instabilities of the organisms thus artificially fabricated. Data is then provided from both official agencies as well as existing literature questioning the accuracy and reliability of the risk analyses as to these organisms being harmless to health and discusses the almost total lack of scientific studies analyzing the health safety/dangerousness of transgenic foods. Given all these unknowns, other factors must be taken into account, particularly genetic contamination of the non-genetically modified crops, which is now starting to become widespread in some parts of the world. Not being able of reversing the situation in the even of problems is irresponsible. Other major aspects are the impacts on the environment (such as insects building up resistances, the loss of biodiversity, the increase in chemical products employed) with indirect repercussions on health and/or future food production. Lastly, thoughts for discussion are added concerning food safety in terms of food availability and food sovereignty, given that the transgenic seed and related agrochemicals market is currently cornered by five large-scale transnational companies. The conclusion entails an analysis of biotechnological agriculture's contribution to sustainability.

  13. MaizeCyc: Metabolic networks in maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    MaizeCyc is a catalog of known and predicted metabolic and transport pathways that enables plant researchers to graphically represent the metabolome of maize (Zea mays), thereby supporting integrated systems-biology analysis. Supported analyses include molecular and genetic/phenotypic profiling (e.g...

  14. Genetic basis and detection of unintended effects in genetically modified crop plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In January 2014, an international meeting sponsored by the International Life Sciences Institute/Health and Environmental Sciences Institute and the Canadian Food Inspection Agency titled “Genetic Basis of Unintended Effects in Modified Plants” was held in Ottawa, Canada, bringing together over 75 s...

  15. Ecological impacts of genetically modified crops: ten years of field research and commercial cultivation.

    PubMed

    Sanvido, Olivier; Romeis, Jörg; Bigler, Franz

    2007-01-01

    The worldwide commercial cultivation of genetically modified (GM) crops has raised concerns about potential adverse effects on the environment resulting from the use of these crops. Consequently, the risks of GM crops for the environment, and especially for biodiversity, have been extensively assessed before and during their commercial cultivation. Substantial scientific data on the environmental effects of the currently commercialized GM crops are available today. We have reviewed this scientific knowledge derived from the past 10 years of worldwide experimental field research and commercial cultivation. The review focuses on the currently commercially available GM crops that could be relevant for agriculture in Western and Central Europe (i.e., maize, oilseed rape, and soybean), and on the two main GM traits that are currently commercialized, herbicide tolerance (HT) and insect resistance (IR). The sources of information included peer-reviewed scientific journals, scientific books, reports from regions with extensive GM crop cultivation, as well as reports from international governmental organizations. The data available so far provide no scientific evidence that the cultivation of the presently commercialized GM crops has caused environmental harm. Nevertheless, a number of issues related to the interpretation of scientific data on effects of GM crops on the environment are debated controversially. The present review highlights these scientific debates and discusses the effects of GM crop cultivation on the environment considering the impacts caused by cultivation practices of modern agricultural systems.

  16. The global income and production effects of genetically modified (GM) crops 1996-2011.

    PubMed

    Brookes, Graham; Barfoot, Peter

    2013-01-01

    A key part of any assessment of the global value of crop biotechnology in agriculture is an examination of its economic impact at the farm level. This paper follows earlier annual studies which examined economic impacts on yields, key costs of production, direct farm income and effects and impacts on the production base of the four main crops of soybeans, corn, cotton and canola. The commercialization of genetically modified (GM) crops has continued to occur at a rapid rate, with important changes in both the overall level of adoption and impact occurring in 2011. This annual updated analysis shows that there have been very significant net economic benefits at the farm level amounting to $19.8 billion in 2011 and $98.2 billion for the 16 year period (in nominal terms). The majority (51.2%) of these gains went to farmers in developing countries. GM technology have also made important contributions to increasing global production levels of the four main crops, having added 110 million tonnes and 195 million tonnes respectively, to the global production of soybeans and maize since the introduction of the technology in the mid-1990s.

  17. A Meta-Analysis of the Impacts of Genetically Modified Crops

    PubMed Central

    Klümper, Wilhelm; Qaim, Matin

    2014-01-01

    Background Despite the rapid adoption of genetically modified (GM) crops by farmers in many countries, controversies about this technology continue. Uncertainty about GM crop impacts is one reason for widespread public suspicion. Objective We carry out a meta-analysis of the agronomic and economic impacts of GM crops to consolidate the evidence. Data Sources Original studies for inclusion were identified through keyword searches in ISI Web of Knowledge, Google Scholar, EconLit, and AgEcon Search. Study Eligibility Criteria Studies were included when they build on primary data from farm surveys or field trials anywhere in the world, and when they report impacts of GM soybean, maize, or cotton on crop yields, pesticide use, and/or farmer profits. In total, 147 original studies were included. Synthesis Methods Analysis of mean impacts and meta-regressions to examine factors that influence outcomes. Results On average, GM technology adoption has reduced chemical pesticide use by 37%, increased crop yields by 22%, and increased farmer profits by 68%. Yield gains and pesticide reductions are larger for insect-resistant crops than for herbicide-tolerant crops. Yield and profit gains are higher in developing countries than in developed countries. Limitations Several of the original studies did not report sample sizes and measures of variance. Conclusion The meta-analysis reveals robust evidence of GM crop benefits for farmers in developed and developing countries. Such evidence may help to gradually increase public trust in this technology. PMID:25365303

  18. Multitarget real-time PCR-based system: monitoring for unauthorized genetically modified events in India.

    PubMed

    Randhawa, Gurinder Jit; Singh, Monika; Sood, Payal; Bhoge, Rajesh K

    2014-07-23

    A multitarget TaqMan real-time PCR (RTi-PCR) based system was developed to monitor unauthorized genetically modified (GM) events in India. Most of the GM events included in this study are either authorized for commercial cultivation or field trials, which were indigenously developed or imported for research purposes. The developed system consists of a 96-well prespotted plate with lyophilized primers and probes, for simultaneous detection of 47 targets in duplicate, including 21 event-specific sequences, 5 construct regions, 15 for transgenic elements, and 6 taxon-specific targets for cotton, eggplant, maize, potato, rice, and soybean. Limit of detection (LOD) of assays ranged from 0.1 to 0.01% GM content for different targets. Applicability, robustness, and practical utility of the developed system were verified with stacked GM cotton event, powdered samples of proficiency testing and two unknown test samples. This user-friendly multitarget approach can be efficiently utilized for monitoring the unauthorized GM events in an Indian context.

  19. Unintended effects in genetically modified crops: revealed by metabolomics?

    PubMed

    Rischer, Heiko; Oksman-Caldentey, Kirsi-Marja

    2006-03-01

    In Europe the commercialization of food derived from genetically modified plants has been slow because of the complex regulatory process and the concerns of consumers. Risk assessment is focused on potential adverse effects on humans and the environment, which could result from unintended effects of genetic modifications: unintended effects are connected to changes in metabolite levels in the plants. One of the major challenges is how to analyze the overall metabolite composition of GM plants in comparison to conventional cultivars, and one possible solution is offered by metabolomics. The ultimate aim of metabolomics is the identification and quantification of all small molecules in an organism; however, a single method enabling complete metabolome analysis does not exist. Given a comprehensive extraction method, a hierarchical strategy--starting with global fingerprinting and followed by complementary profiling attempts--is the most logical and economic approach to detect unintended effects in GM crops.

  20. Genetically modified mesenchymal stem cells for improved islet transplantation.

    PubMed

    Wu, Hao; Ye, Zhaoyang; Mahato, Ram I

    2011-10-03

    The use of adult stem cells for therapeutic purposes has met with great success in recent years. Among several types of adult stem cells, mesenchymal stem cells (MSCs) derived from bone marrow (BM) and other sources have gained popularity for basic research and clinical applications because of their therapeutic potential in treating a variety of diseases. Because of their tissue regeneration potential and immune modulation effect, MSCs were recently used as cell-based therapy to promote revascularization, increase pancreatic β-cell proliferation, and avoid allograft rejection in islet transplantation. Taking advantage of the recent progress in gene therapy, genetically modified MSCs can further enhance and expand the therapeutic benefit of primary MSCs while retaining their stem-cell-like properties. This review aims to gain a thorough understanding of the current obstacles to successful islet transplantation and discusses the potential role of primary MSCs before or after genetic modification in islet transplantation.

  1. Safety assessment and detection methods of genetically modified organisms.

    PubMed

    Xu, Rong; Zheng, Zhe; Jiao, Guanglian

    2014-01-01

    Genetically modified organisms (GMOs), are gaining importance in agriculture as well as the production of food and feed. Along with the development of GMOs, health and food safety concerns have been raised. These concerns for these new GMOs make it necessary to set up strict system on food safety assessment of GMOs. The food safety assessment of GMOs, current development status of safety and precise transgenic technologies and GMOs detection have been discussed in this review. The recent patents about GMOs and their detection methods are also reviewed. This review can provide elementary introduction on how to assess and detect GMOs.

  2. [The lack of information on genetically modified organisms in Brazil].

    PubMed

    Ribeiro, Isabelle Geoffroy; Marin, Victor Augustus

    2012-02-01

    This article presents a review about the labeling of products that have Genetically Modified Organisms (GMO), also called transgenic elements in their composition. It addresses the conventions, laws and regulations relating to such products currently governing the market, the adequacy of these existing standards and their acceptance by society. It also examines the importance of the cautionary principle when assessing the application of new technologies or technologies where little is known or where there is no relevant scientific knowledge about the potential risks to the environment, human health and society.

  3. [Unintended effects assessment of genetically modified crops using omics techniques].

    PubMed

    Zhao, Yan; Li, Yan-Yan

    2013-12-01

    Safety assessment is the essential process for commercial application of genetically modified (GM) crops. Omics techniques can be used to evaluate the safety of GM crops unbiasedly at different biological levels, such as transcripts, proteins and metabolites. In the present review, the researches on unintended effects assessment of GM crops using transcriptomic, proteomic and metabolomic techniques in recent ten years have been summarized. The facts show that the environmental factors (growing area and season) and genotype difference play greater roles than gene insertion does for most unintended variations in GM crops.

  4. Safety assessment of genetically modified plants with deliberately altered composition.

    PubMed

    Halford, Nigel G; Hudson, Elizabeth; Gimson, Amy; Weightman, Richard; Shewry, Peter R; Tompkins, Steven

    2014-08-01

    The development and marketing of 'novel' genetically modified (GM) crops in which composition has been deliberately altered poses a challenge to the European Union (EU)'s risk assessment processes, which are based on the concept of substantial equivalence with a non-GM comparator. This article gives some examples of these novel GM crops and summarizes the conclusions of a report that was commissioned by the European Food Safety Authority on how the EU's risk assessment processes could be adapted to enable their safety to be assessed.

  5. Safety assessment of genetically modified plants with deliberately altered composition

    PubMed Central

    Halford, Nigel G; Hudson, Elizabeth; Gimson, Amy; Weightman, Richard; Shewry, Peter R; Tompkins, Steven

    2014-01-01

    The development and marketing of ‘novel’ genetically modified (GM) crops in which composition has been deliberately altered poses a challenge to the European Union (EU)'s risk assessment processes, which are based on the concept of substantial equivalence with a non-GM comparator. This article gives some examples of these novel GM crops and summarizes the conclusions of a report that was commissioned by the European Food Safety Authority on how the EU's risk assessment processes could be adapted to enable their safety to be assessed. PMID:24735114

  6. Genetic variability of the phloem sap metabolite content of maize (Zea mays L.) during the kernel-filling period.

    PubMed

    Yesbergenova-Cuny, Zhazira; Dinant, Sylvie; Martin-Magniette, Marie-Laure; Quilleré, Isabelle; Armengaud, Patrick; Monfalet, Priscilla; Lea, Peter J; Hirel, Bertrand

    2016-11-01

    Using a metabolomic approach, we have quantified the metabolite composition of the phloem sap exudate of seventeen European and American lines of maize that had been previously classified into five main groups on the basis of molecular marker polymorphisms. In addition to sucrose, glutamate and aspartate, which are abundant in the phloem sap of many plant species, large quantities of aconitate and alanine were also found in the phloem sap exudates of maize. Genetic variability of the phloem sap composition was observed in the different maize lines, although there was no obvious relationship between the phloem sap composition and the five previously classified groups. However, following hierarchical clustering analysis there was a clear relationship between two of the subclusters of lines defined on the basis of the composition of the phloem sap exudate and the earliness of silking date. A comparison between the metabolite contents of the ear leaves and the phloem sap exudates of each genotype, revealed that the relative content of most of the carbon- and nitrogen-containing metabolites was similar. Correlation studies performed between the metabolite content of the phloem sap exudates and yield-related traits also revealed that for some carbohydrates such as arabitol and sucrose there was a negative or positive correlation with kernel yield and kernel weight respectively. A posititive correlation was also found between kernel number and soluble histidine.

  7. Benefits and risks associated with genetically modified food products.

    PubMed

    Kramkowska, Marta; Grzelak, Teresa; Czyżewska, Krystyna

    2013-01-01

    Scientists employing methods of genetic engineering have developed a new group of living organisms, termed 'modified organisms', which found application in, among others, medicine, the pharmaceutical industry and food distribution. The introduction of transgenic products to the food market resulted in them becoming a controversial topic, with their proponents and contestants. The presented study aims to systematize objective data on the potential benefits and risks resulting from the consumption of transgenic food. Genetic modifications of plants and animals are justified by the potential for improvement of the food situation worldwide, an increase in yield crops, an increase in the nutritional value of food, and the development of pharmaceutical preparations of proven clinical significance. In the opinions of critics, however, transgenic food may unfavourably affect the health of consumers. Therefore, particular attention was devoted to the short- and long-lasting undesirable effects, such as alimentary allergies, synthesis of toxic agents or resistance to antibiotics. Examples arguing for the justified character of genetic modifications and cases proving that their use can be dangerous are innumerable. In view of the presented facts, however, complex studies are indispensable which, in a reliable way, evaluate effects linked to the consumption of food produced with the application of genetic engineering techniques. Whether one backs up or negates transgenic products, the choice between traditional and non-conventional food remains to be decided exclusively by the consumers.

  8. A genetic relationship between nitrogen use efficiency and seedling root traits in maize as revealed by QTL analysis

    PubMed Central

    Li, Pengcheng; Chen, Fanjun; Cai, Hongguang; Liu, Jianchao; Pan, Qingchun; Liu, Zhigang; Gu, Riliang; Mi, Guohua; Zhang, Fusuo; Yuan, Lixing

    2015-01-01

    That root system architecture (RSA) has an essential role in nitrogen acquisition is expected in maize, but the genetic relationship between RSA and nitrogen use efficiency (NUE) traits remains to be elucidated. Here, the genetic basis of RSA and NUE traits was investigated in maize using a recombination inbred line population that was derived from two lines contrasted for both traits. Under high-nitrogen and low-nitrogen conditions, 10 NUE- and 9 RSA-related traits were evaluated in four field environments and three hydroponic experiments, respectively. In contrast to nitrogen utilization efficiency (NutE), nitrogen uptake efficiency (NupE) had significant phenotypic correlations with RSA, particularly the traits of seminal roots (r = 0.15–0.31) and crown roots (r = 0.15–0.18). A total of 331 quantitative trait loci (QTLs) were detected, including 184 and 147 QTLs for NUE- and RSA-related traits, respectively. These QTLs were assigned into 64 distinct QTL clusters, and ~70% of QTLs for nitrogen-efficiency (NUE, NupE, and NutE) coincided in clusters with those for RSA. Five important QTLs clusters at the chromosomal regions bin1.04, 2.04, 3.04, 3.05/3.06, and 6.07/6.08 were found in which QTLs for both traits had favourable effects from alleles coming from the large-rooted and high-NupE parent. Introgression of these QTL clusters in the advanced backcross-derived lines conferred mean increases in grain yield of ~14.8% for the line per se and ~15.9% in the testcross. These results reveal a significant genetic relationship between RSA and NUE traits, and uncover the most promising genomic regions for marker-assisted selection of RSA to improve NUE in maize. PMID:25873660

  9. A genetic relationship between nitrogen use efficiency and seedling root traits in maize as revealed by QTL analysis.

    PubMed

    Li, Pengcheng; Chen, Fanjun; Cai, Hongguang; Liu, Jianchao; Pan, Qingchun; Liu, Zhigang; Gu, Riliang; Mi, Guohua; Zhang, Fusuo; Yuan, Lixing

    2015-06-01

    That root system architecture (RSA) has an essential role in nitrogen acquisition is expected in maize, but the genetic relationship between RSA and nitrogen use efficiency (NUE) traits remains to be elucidated. Here, the genetic basis of RSA and NUE traits was investigated in maize using a recombination inbred line population that was derived from two lines contrasted for both traits. Under high-nitrogen and low-nitrogen conditions, 10 NUE- and 9 RSA-related traits were evaluated in four field environments and three hydroponic experiments, respectively. In contrast to nitrogen utilization efficiency (NutE), nitrogen uptake efficiency (NupE) had significant phenotypic correlations with RSA, particularly the traits of seminal roots (r = 0.15-0.31) and crown roots (r = 0.15-0.18). A total of 331 quantitative trait loci (QTLs) were detected, including 184 and 147 QTLs for NUE- and RSA-related traits, respectively. These QTLs were assigned into 64 distinct QTL clusters, and ~70% of QTLs for nitrogen-efficiency (NUE, NupE, and NutE) coincided in clusters with those for RSA. Five important QTLs clusters at the chromosomal regions bin1.04, 2.04, 3.04, 3.05/3.06, and 6.07/6.08 were found in which QTLs for both traits had favourable effects from alleles coming from the large-rooted and high-NupE parent. Introgression of these QTL clusters in the advanced backcross-derived lines conferred mean increases in grain yield of ~14.8% for the line per se and ~15.9% in the testcross. These results reveal a significant genetic relationship between RSA and NUE traits, and uncover the most promising genomic regions for marker-assisted selection of RSA to improve NUE in maize.

  10. Ionic liquids as novel solvents for biosynthesis of octenyl succinic anhydride-modified waxy maize starch.

    PubMed

    Li, Dandan; Zhang, Xiwen; Tian, Yaoqi

    2016-05-01

    Biosynthesis of octenyl succinic anhydride (OSA) starch was investigated using ionic liquids (ILs) as reaction media. Waxy maize starch was pretreated in 1-butyl-3-methylimidazolium chlorine and then esterified with OSA in 1-octyl-3-methylimidazolium nitrate by using Novozyme 435 as catalyst. The degree of substitution of OSA starch reached 0.0130 with 5 wt% starch concentration and 1 wt% lipase dosage based on ILs weight at 50 °C for 3h. The formation of OSA starch was confirmed by fourier transform infrared spectroscopy. Scanning electron microscopy and X-ray diffraction revealed that the morphology and crystal structure of starch were significantly destroyed. Thermogravimetric analysis showed that esterification decreased the thermal stability of starch. The successful lipase-catalyzed synthesis of OSA starch in ILs suggests that ILs are potential replacement of traditional organic solvents for starch ester biosynthesis.

  11. The Genetic Basis of Haploid Induction in Maize Identified with a Novel Genome-Wide Association Method.

    PubMed

    Hu, Haixiao; Schrag, Tobias A; Peis, Regina; Unterseer, Sandra; Schipprack, Wolfgang; Chen, Shaojiang; Lai, Jinsheng; Yan, Jianbing; Prasanna, Boddupalli M; Nair, Sudha K; Chaikam, Vijay; Rotarenco, Valeriu; Shatskaya, Olga A; Zavalishina, Alexandra; Scholten, Stefan; Schön, Chris-Carolin; Melchinger, Albrecht E

    2016-04-01

    In vivo haploid induction (HI) triggered by pollination with special intraspecific genotypes, called inducers, is unique to Zea maysL. within the plant kingdom and has revolutionized maize breeding during the last decade. However, the molecular mechanisms underlying HI in maize are still unclear. To investigate the genetic basis of HI, we developed a new approach for genome-wide association studies (GWAS), termed conditional haplotype extension (CHE) test that allows detection of selective sweeps even under almost perfect confounding of population structure and trait expression. Here, we applied this test to identify genomic regions required for HI expression and dissected the combined support interval (50.34 Mb) of the QTL qhir1, detected in a previous study, into two closely linked genomic segments relevant for HI expression. The first, termed qhir11(0.54 Mb), comprises an already fine-mapped region but was not diagnostic for differentiating inducers and noninducers. The second segment, termed qhir12(3.97 Mb), had a haplotype allele common to all 53 inducer lines but not found in any of the 1482 noninducers. By comparing resequencing data of one inducer with 14 noninducers, we detected in the qhir12 region three candidate genes involved in DNA or amino acid binding, however, none for qhir11 We propose that the CHE test can be utilized in introgression breeding and different fields of genetics to detect selective sweeps in heterogeneous genetic backgrounds.

  12. Systems genetics reveals a transcriptional network associated with susceptibility in the maize-grey leaf spot pathosystem.

    PubMed

    Christie, Nanette; Myburg, Alexander A; Joubert, Fourie; Murray, Shane L; Carstens, Maryke; Lin, Yao-Cheng; Meyer, Jacqueline; Crampton, Bridget G; Christensen, Shawn A; Ntuli, Jean F; Wighard, Sara S; Van de Peer, Yves; Berger, Dave K

    2017-02-01

    We used a systems genetics approach to elucidate the molecular mechanisms of the responses of maize to grey leaf spot (GLS) disease caused by Cercospora zeina, a threat to maize production globally. Expression analysis of earleaf samples in a subtropical maize recombinant inbred line population (CML444 × SC Malawi) subjected in the field to C. zeina infection allowed detection of 20 206 expression quantitative trait loci (eQTLs). Four trans-eQTL hotspots coincided with GLS disease QTLs mapped in the same field experiment. Co-expression network analysis identified three expression modules correlated with GLS disease scores. The module (GY-s) most highly correlated with susceptibility (r = 0.71; 179 genes) was enriched for the glyoxylate pathway, lipid metabolism, diterpenoid biosynthesis and responses to pathogen molecules such as chitin. The GY-s module was enriched for genes with trans-eQTLs in hotspots on chromosomes 9 and 10, which also coincided with phenotypic QTLs for susceptibility to GLS. This transcriptional network has significant overlap with the GLS susceptibility response of maize line B73, and may reflect pathogen manipulation for nutrient acquisition and/or unsuccessful defence responses, such as kauralexin production by the diterpenoid biosynthesis pathway. The co-expression module that correlated best with resistance (TQ-r; 1498 genes) was enriched for genes with trans-eQTLs in hotspots coinciding with GLS resistance QTLs on chromosome 9. Jasmonate responses were implicated in resistance to GLS through co-expression of COI1 and enrichment of genes with the Gene Ontology term 'cullin-RING ubiquitin ligase complex' in the TQ-r module. Consistent with this, JAZ repressor expression was highly correlated with the severity of GLS disease in the GY-s susceptibility network.

  13. A 90-day toxicity study of GmTMT transgenic maize in Sprague-Dawley rats.

    PubMed

    Fang, Jin; Feng, Yongquan; Zhi, Yuan; Zhang, Lan; Yu, Zhou; Jia, Xudong

    2017-04-01

    GmTMT transgenic maize is a genetically modified maize plant that overexpresses the γ-tocopherol methyltransferase (γ-TMT) from Glycine max (Gm). The γ-TMT gene was introduced into maize line Zhen58 to encode the GmTMT2a protein which can convert γ-tocopherol into α-tocopherol. Overexpression of GmTMT2a significantly increased the α-tocopherol content in transgenic maize. The present study was designed to investigate any potential effects of GmTMT maize grain in a 90-day subchronic rodent feeding study. Maize grains from GmTMT or Zhen58 were incorporated into rodent diets at low (12.5%), medium (25%) or high (50%) concentrations and administered to Sprague-Dawley rats (n = 10/sex/group) for 90 days. The negative control group of rats (n = 10/sex/group) were fed with common maize diets. Results from body weights, feed consumption, clinical chemistry, hematology, absolute and relative organ weights indicated no treatment-related side effects of GmTMT maize grain on rats in comparison with rats consuming diets containing Zhen58 maize grain. In addition, no treatment-related changes were found in necropsy and histopathology examinations. Altogether, our data indicates that GmTMT transgenic maize is as safe and nutritious as its conventional non-transgenic maize.

  14. Stover Composition in Maize and Sorghum Reveals Remarkable Genetic Variation and Plasticity for Carbohydrate Accumulation

    PubMed Central

    Sekhon, Rajandeep S.; Breitzman, Matthew W.; Silva, Renato R.; Santoro, Nicholas; Rooney, William L.; de Leon, Natalia; Kaeppler, Shawn M.

    2016-01-01

    Carbohydrates stored in vegetative organs, particularly stems, of grasses are a very important source of energy. We examined carbohydrate accumulation in adult sorghum and maize hybrids with distinct phenology and different end uses (grain, silage, sucrose or sweetness in stalk juice, and biomass). Remarkable variation was observed for non-structural carbohydrates and structural polysaccharides during three key developmental stages both between and within hybrids developed for distinct end use in both species. At the onset of the reproductive phase (average 65 days after planting, DAP), a wide range for accumulation of non-structural carbohydrates (free glucose and sucrose combined), was observed in internodes of maize (11–24%) and sorghum (7–36%) indicating substantial variation for transient storage of excess photosynthate during periods of low grain or vegetative sink strength. Remobilization of these reserves for supporting grain fill or vegetative growth was evident from lower amounts in maize (8–19%) and sorghum (9–27%) near the end of the reproductive period (average 95 DAP). At physiological maturity of grain hybrids (average 120 DAP), amounts of these carbohydrates were generally unchanged in maize (9–21%) and sorghum (16–27%) suggesting a loss of photosynthetic assimilation due to weakening sink demand. Nonetheless, high amounts of non-structural carbohydrates at maturity even in grain maize and sorghum (15–18%) highlight the potential for developing dual-purpose (grain/stover) crops. For both species, the amounts of structural polysaccharides in the cell wall, measured as monomeric components (glucose and pentose), decreased during grain fill but remained unchanged thereafter with maize biomass possessing slightly higher amounts than sorghum. Availability of carbohydrates in maize and sorghum highlights the potential for developing energy-rich dedicated biofuel or dual-purpose (grain/stover) crops. PMID:27375668

  15. Stover composition in maize and sorghum reveals remarkable genetic variation and plasticity for carbohydrate accumulation

    SciTech Connect

    Sekhon, Rajandeep S.; Breitzman, Matthew W.; Silva, Renato R.; Santoro, Nicholas; Rooney, William L.; de Leon, Natalia; Kaeppler, Shawn M.

    2016-06-08

    Carbohydrates stored in vegetative organs, particularly stems, of grasses are a very important source of energy. We examined carbohydrate accumulation in adult sorghum and maize hybrids with distinct phenology and different end uses (grain, silage, sucrose or sweetness in stalk juice, and biomass). Remarkable variation was observed for nonstructural carbohydrates and structural polysaccharides during three key developmental stages both between and within hybrids developed for distinct end use in both species. At the onset of the reproductive phase (average 65 days after planting, DAP), a wide range for accumulation of non-structural carbohydrates (free glucose and sucrose combined), was observed in internodes of maize (11-24%) and sorghum (7-36%) indicating substantial variation for transient storage of excess photosynthate during periods of low grain or vegetative sink strength. Remobilization of these reserves for supporting grain fill or vegetative growth was evident from lower amounts in maize (8-19%) and sorghum (9-27%) near the end of the reproductive period (average 95 DAP). At physiological maturity of grain hybrids (average 120 DAP), amounts of these carbohydrates were generally unchanged in maize (9-21%) and sorghum (16-27%) suggesting a loss of photosynthetic assimilation due to weakening sink demand. Nonetheless, high amounts of non-structural carbohydrates at maturity even in grain maize and sorghum (15-18%) highlight the potential for developing dual-purpose (grain/stover) crops. For both species, the amounts of structural polysaccharides in the cell wall, measured as monomeric components (glucose and pentose), decreased during grain fill but remained unchanged thereafter with maize biomass possessing slightly higher amounts than sorghum. In conclusion, availability of carbohydrates in maize and sorghum highlights the potential for developing energy-rich dedicated biofuel or dual-purpose (grain/stover) crops.

  16. Stover composition in maize and sorghum reveals remarkable genetic variation and plasticity for carbohydrate accumulation

    DOE PAGES

    Sekhon, Rajandeep S.; Breitzman, Matthew W.; Silva, Renato R.; ...

    2016-06-08

    Carbohydrates stored in vegetative organs, particularly stems, of grasses are a very important source of energy. We examined carbohydrate accumulation in adult sorghum and maize hybrids with distinct phenology and different end uses (grain, silage, sucrose or sweetness in stalk juice, and biomass). Remarkable variation was observed for nonstructural carbohydrates and structural polysaccharides during three key developmental stages both between and within hybrids developed for distinct end use in both species. At the onset of the reproductive phase (average 65 days after planting, DAP), a wide range for accumulation of non-structural carbohydrates (free glucose and sucrose combined), was observed inmore » internodes of maize (11-24%) and sorghum (7-36%) indicating substantial variation for transient storage of excess photosynthate during periods of low grain or vegetative sink strength. Remobilization of these reserves for supporting grain fill or vegetative growth was evident from lower amounts in maize (8-19%) and sorghum (9-27%) near the end of the reproductive period (average 95 DAP). At physiological maturity of grain hybrids (average 120 DAP), amounts of these carbohydrates were generally unchanged in maize (9-21%) and sorghum (16-27%) suggesting a loss of photosynthetic assimilation due to weakening sink demand. Nonetheless, high amounts of non-structural carbohydrates at maturity even in grain maize and sorghum (15-18%) highlight the potential for developing dual-purpose (grain/stover) crops. For both species, the amounts of structural polysaccharides in the cell wall, measured as monomeric components (glucose and pentose), decreased during grain fill but remained unchanged thereafter with maize biomass possessing slightly higher amounts than sorghum. In conclusion, availability of carbohydrates in maize and sorghum highlights the potential for developing energy-rich dedicated biofuel or dual-purpose (grain/stover) crops.« less

  17. Plant potassium content modifies the effects of arbuscular mycorrhizal symbiosis on root hydraulic properties in maize plants.

    PubMed

    El-Mesbahi, Mohamed Najib; Azcón, Rosario; Ruiz-Lozano, Juan Manuel; Aroca, Ricardo

    2012-10-01

    It is well known that the arbuscular mycorrhizal (AM) symbiosis helps the host plant to overcome several abiotic stresses including drought. One of the mechanisms for this drought tolerance enhancement is the higher water uptake capacity of the mycorrhizal plants. However, the effects of the AM symbiosis on processes regulating root hydraulic properties of the host plant, such as root hydraulic conductivity and plasma membrane aquaporin gene expression, and protein abundance, are not well defined. Since it is known that K(+) status is modified by AM and that it regulates root hydraulic properties, it has been tested how plant K(+) status could modify the effects of the symbiosis on root hydraulic conductivity and plasma membrane aquaporin gene expression and protein abundance, using maize (Zea mays L.) plants and Glomus intraradices as a model. It was observed that the supply of extra K(+) increased root hydraulic conductivity only in AM plants. Also, the different pattern of plasma membrane aquaporin gene expression and protein abundance between AM and non-AM plants changed with the application of extra K(+). Thus, plant K(+) status could be one of the causes of the different observed effects of the AM symbiosis on root hydraulic properties. The present study also highlights the critical importance of AM fungal aquaporins in regulating root hydraulic properties of the host plant.

  18. Comparative diversity of arthropods on Bt maize and non-Bt maize in two different cropping systems in South Africa.

    PubMed

    Truter, J; Van Hamburg, H; Van Den Berg, J

    2014-02-01

    The biodiversity of an agroecosystem is not only important for its intrinsic value but also because it influences ecological functions that are vital for crop production in sustainable agricultural systems and the surrounding environment. A concern about genetically modified (GM) crops is the potential negative impact that such crops could have on diversity and abundance of nontarget organisms, and subsequently on ecosystem functions. Therefore, it is essential to assess the potential environmental risk of the release of a GM crop and to study its effect on species assemblages within that ecosystem. Assessment of the impact of Bt maize on the environment is hampered by the lack of basic checklists of species present in maize agroecosystems. The aims of the study were to compile a checklist of arthropods that occur on maize in South Africa and to compare the diversity and abundance of arthropods and functional groups on Bt maize and non-Bt maize. Collections of arthropods were carried out during two growing seasons on Bt maize and non-Bt maize plants at two localities. Three maize fields were sampled per locality during each season. Twenty plants, each of Bt maize and non-Bt maize, were randomly selected from the fields at each site. The arthropods collected during this study were classified to morphospecies level and grouped into the following functional groups: detritivores, herbivores, predators, and parasitoids. Based on feeding strategy, herbivores and predators were further divided into sucking herbivores or predators (piercing-sucking mouthparts) and chewing herbivores or predators (chewing mouthparts). A total of 8,771 arthropod individuals, comprising 288 morphospecies and presenting 20 orders, were collected. Results from this short-term study indicated that abundance and diversity of arthropods in maize and the different functional guilds were not significantly affected by Bt maize, either in terms of diversity or abundance.

  19. Genetically modified crops: detection strategies and biosafety issues.

    PubMed

    Kamle, Suchitra; Ali, Sher

    2013-06-15

    Genetically modified (GM) crops are increasingly gaining acceptance but concurrently consumers' concerns are also increasing. The introduction of Bacillus thuringiensis (Bt) genes into the plants has raised issues related to its risk assessment and biosafety. The International Regulations and the Codex guidelines regulate the biosafety requirements of the GM crops. In addition, these bodies synergize and harmonize the ethical issues related to the release and use of GM products. The labeling of GM crops and their products are mandatory if the genetically modified organism (GMO) content exceeds the levels of a recommended threshold. The new and upcoming GM crops carrying multiple stacked traits likely to be commercialized soon warrant sensitive detection methods both at the DNA and protein levels. Therefore, traceability of the transgene and its protein expression in GM crops is an important issue that needs to be addressed on a priority basis. The advancement in the area of molecular biology has made available several bioanalytical options for the detection of GM crops based on DNA and protein markers. Since the insertion of a gene into the host genome may even cause copy number variation, this may be uncovered using real time PCR. Besides, assessing the exact number of mRNA transcripts of a gene, correlation between the template activity and expressed protein may be established. Here, we present an overview on the production of GM crops, their acceptabilities, detection strategies, biosafety issues and potential impact on society. Further, overall future prospects are also highlighted.

  20. Detection and quantification of genetically modified organisms using very short, locked nucleic acid TaqMan probes.

    PubMed

    Salvi, Sergio; D'Orso, Fabio; Morelli, Giorgio

    2008-06-25

    Many countries have introduced mandatory labeling requirements on foods derived from genetically modified organisms (GMOs). Real-time quantitative polymerase chain reaction (PCR) based upon the TaqMan probe chemistry has become the method mostly used to support these regulations; moreover, event-specific PCR is the preferred method in GMO detection because of its high specificity based on the flanking sequence of the exogenous integrant. The aim of this study was to evaluate the use of very short (eight-nucleotide long), locked nucleic acid (LNA) TaqMan probes in 5'-nuclease PCR assays for the detection and quantification of GMOs. Classic TaqMan and LNA TaqMan probes were compared for the analysis of the maize MON810 transgene. The performance of the two types of probes was tested on the maize endogenous reference gene hmga, the CaMV 35S promoter, and the hsp70/cryIA(b) construct as well as for the event-specific 5'-integration junction of MON810, using plasmids as standard reference molecules. The results of our study demonstrate that the LNA 5'-nuclease PCR assays represent a valid and reliable analytical system for the detection and quantification of transgenes. Application of very short LNA TaqMan probes to GMO quantification can simplify the design of 5'-nuclease assays.

  1. Conservation biology, genetically modified organisms, and the biosafety protocol.

    PubMed

    Hill, Ryan; Sendashonga, Cyrie

    2006-12-01

    Concerns have been raised regarding the potential adverse effects on biological diversity of the use of living modified organisms (LMOs, which are commonly known by similar terms such as genetically modified organisms). At the international level these concerns are addressed in part by an agreement known as the Cartagena Protocol on Biosafety and include potential toxic effects of insect-resistant crops on nontarget organisms and potential ecological effects of gene flow from modified crops, fish, microorganisms, or insects to wild species or counterparts. We reviewed the protocol's main provisions, including those dealing with risk assessment and risk management, decision making on imports, documentation accompanying shipments, and liability resulting from damages caused by LMOs. A medium-term program of work has been adopted by the parties, which includes the potential contribution of conservation biologists to delivering capacity building, developing risk assessment guidance, evaluating mechanisms of potential ecological damages from LMOs, and other issues. Conservation biologists and other experts have opportunities to influence the negotiations and implementation of the protocol by providing inputs at meetings, offering expertise to governments and organizations, and participating in or developing relevant projects and initiatives. Involvement of conservation biologists in the implementation and further development of the protocol would contribute to its effectiveness.

  2. Molecular scissors and their application in genetically modified farm animals.

    PubMed

    Petersen, Bjoern; Niemann, Heiner

    2015-06-01

    Molecular scissors (MS), incl. Zinc Finger Nucleases (ZFN), Transcription-activator like endoncleases (TALENS) and meganucleases possess long recognition sites and are thus capable of cutting DNA in a very specific manner. These molecular scissors mediate targeted genetic alterations by enhancing the DNA mutation rate via induction of double-strand breaks at a predetermined genomic site. Compared to conventional homologous recombination based gene targeting, MS can increase the targeting rate 10,000-fold, and gene disruption via mutagenic DNA repair is stimulated at a similar frequency. The successful application of different MS has been shown in different organisms, including insects, amphibians, plants, nematodes, and mammals, including humans. Recently, another novel class of molecular scissors was described that uses RNAs to target a specific genomic site. The CRISPR/Cas9 system is capable of targeting even multiple genomic sites in one shot and thus could be superior to ZFNs or TALEN, especially by its easy design. MS can be successfully employed for improving the understanding of complex physiological systems, producing transgenic animals, incl. creating large animal models for human diseases, creating specific cell lines, and plants, and even for treating human genetic diseases. This review provides an update on molecular scissors, their underlying mechanism and focuses on new opportunities for generating genetically modified farm animals.

  3. Genetic Effects Conferring Heat Tolerance in a Cross of Tolerant × Susceptible Maize (Zea mays L.) Genotypes

    PubMed Central

    Naveed, Muhammad; Ahsan, Muhammad; Akram, Hafiz M.; Aslam, Muhammad; Ahmed, Nisar

    2016-01-01

    Incessant rise in ambient temperature is threatening sustainability of maize productions, worldwide. Breeding heat resilient synthetics/hybrids is the most economical tool while lack of knowledge of gene action controlling heat and yield relevant traits in maize is hampering progress in this regard. The current study, therefore, was conducted using analyses of generation mean and variance, and narrow sense heritability (hn2) and genetic advance as percent of mean (GAM%). Initially, one hundred inbred lines were evaluated for cell membrane thermo-stability and grain yield per plant on mean day/night temperatures of 36.6°C/22.1°C in non-stressed (NS) and 42.7°C/25.7°C in heat-stressed (HS) conditions. From these, one tolerant (ZL-11271) and one susceptible (R-2304-2) genotypes were crossed to develop six basic generations, being evaluated on mean day/night temperatures of 36.1°C/22.8°C (NS) and 42.3°C/25.9°C (HS) in factorial randomized complete block design with three replications. Non-allelic additive-dominance genetic effects were recorded for most traits in both conditions except transpiration rate, being controlled by additive epistatic effects in NS regime. Dissection of genetic variance into additive (D), dominance (H), environment (E) and interaction (F) components revealed significance of only DE variances in HS condition than DE, DFE and DHE variances in NS regime which hinted at the potential role of environments in breeding maize for high temperature tolerance. Additive variance was high for majority of traits in both environments except ear length in NS condition where dominance was at large. Higher magnitudes of σD,2 hn2 and GAM% for cell membrane thermo-stability, transpiration rate, leaf firing, ear length, kernels per ear and grain yield per plant in both regimes implied that simple selections might be sufficient for further improvement of these traits. Low-to-moderate GAM% for leaf temperature and 100-grain weight in both conditions

  4. Identification of Associations Between Genetic Factors and Asthma that are Modified by Obesity

    DTIC Science & Technology

    2016-06-01

    AFRL-SA-WP-TR-2016-0010 Identification of Associations Between Genetic Factors and Asthma That Are Modified by Obesity Andrew T...Between Genetic Factors and Asthma That Are Modified by Obesity 5a. CONTRACT NUMBER FA8650-13-2-6371 5b. GRANT NUMBER 5c. PROGRAM ELEMENT...3 3.4 SNP Genetic Analysis ...................................................................................................... 4 3.5

  5. Production and characterization of genetically modified human IL-11 variants.

    PubMed

    Sano, Emiko; Takei, Toshiaki; Ueda, Takuya; Tsumoto, Kouhei

    2017-02-01

    Interleukin-11 (IL-11) has been expected as a drug on severe thrombocytopenia caused by myelo-suppressive chemotherapy. Whereas, development of IL-11 inhibitor is also expected for a treatment against IL-11 related cancer progression. Here, we will demonstrate the creation of various kinds of genetically modified hIL-11s. Modified vectors were constructed by introducing N- or O-glycosylation site on the region of hIL-11 that does not belong to the core α-helical motif based on the predicted secondary structure. N-terminal (N: between 22 to 23 aa), the first loop (M1:70 to 71 aa), the second loop (M2:114-115 aa), the third loop (M3:160-161 aa) and C-terminal (C: 200- aa) were selected for modification. A large scale production system was established and the characteristics of modified hIL-11s were evaluated. The structure was analyzed by amino acid sequence and composition analysis and CD-spectra. Glycan was assessed by monosaccharide composition analysis. Growth promoting activity and biological stability were analyzed by proliferation of T1165 cells. N-terminal modified proteins were well glycosylated and produced. Growth activity of 3NN with NASNASNAS sequence on N-terminal was about tenfold higher than wild type (WT). Structural and biological stabilities of 3NN were also better than WT and residence time in mouse blood was longer than WT. M1 variants lacked growth activity though they are well glycosylated and secondary structure is very stable. Both of 3NN and OM1 with AAATPAPG on M1 associated with hIL-11R strongly. These results indicate N-terminal and M1 variants will be expected for practical use as potent agonists or antagonists of hIL-11.

  6. Genetic Analysis of Grain Filling Rate Using Conditional QTL Mapping in Maize

    PubMed Central

    Cui, Zitian; Hu, Yanmin; Wang, Bin; Tang, Jihua

    2013-01-01

    The grain filling rate (GFR) is an important dynamic trait that determines the final grain yield and is controlled by a network of genes and environment factors. To determine the genetic basis of the GFR, a conditional quantitative trait locus (QTL) analysis method was conducted using time-related phenotypic values of the GFR collected from a set of 243 immortalized F2 (IF2) population, which were evaluated at two locations over 2 years. The GFR gradually rose in the 0–15 days after pollination (DAP) and 16–22 DAP, reaching a maximum at 23–29 DAP, and then gradually decreasing. The variation of kernel weight (KW) was mainly decided by the GFR, and not by the grain filling duration (GFD). Thirty-three different unconditional QTLs were identified for the GFR at the six sampling stages over 2 years. Among them, QTLs qGFR7b, qGFR9 and qGFR6d were identified at the same stages at two locations over 2 years. In addition, 14 conditional QTLs for GFR were detected at five stages. The conditional QTL qGFR7c was identified at stage V|IV (37–43 DAP) at two locations over 2 years, and qGFR7b was detected at the sixth stage (44–50 DAP) in all four environments, except at Anyang location in 2009. QTLs qQTL7b and qQTL6f were identified by unconditional and conditional QTL mapping at the same stages, and might represent major QTLs for regulating the GFR in maize in the IF2 population. Moreover, most of the QTLs identified were co-located with QTLs from previous studies that were associated with GFR, enzyme activities of starch synthesis, soluble carbohydrates, and grain filling related genes. These results indicated that the GFR is regulated by many genes, which are specifically expressed at different grain filling stages, and the specific expression of the genes between 16–35 DAP might be very important for deciding the final kernel weight. PMID:23441180

  7. Optimal control strategy of malaria vector using genetically modified mosquitoes.

    PubMed

    Rafikov, M; Bevilacqua, L; Wyse, A P P

    2009-06-07

    The development of transgenic mosquitoes that are resistant to diseases may provide a new and effective weapon of diseases control. Such an approach relies on transgenic mosquitoes being able to survive and compete with wild-type populations. These transgenic mosquitoes carry a specific code that inhibits the plasmodium evolution in its organism. It is said that this characteristic is hereditary and consequently the disease fades away after some time. Once transgenic mosquitoes are released, interactions between the two populations and inter-specific mating between the two types of mosquitoes take place. We present a mathematical model that considers the generation overlapping and variable environment factors. Based on this continuous model, the malaria vector control is formulated and solved as an optimal control problem, indicating how genetically modified mosquitoes should be introduced in the environment. Numerical simulations show the effectiveness of the proposed control.

  8. Environmental risk assessment for medicinal products containing genetically modified organisms.

    PubMed

    Anliker, B; Longhurst, S; Buchholz, C J

    2010-01-01

    Many gene therapy medicinal products and also some vaccines consist of, or contain, genetically modified organisms (GMOs), which require specific consideration in the environmental risk assessment (ERA) before marketing authorisation or clinical trial applications. The ERA is performed in order to identify the potential risks for public health and the environment, which may arise due to the clinical use of these medicinal products. If such environmental risks are identified and considered as not acceptable, the ERA should go on to propose appropriate risk management strategies capable to reduce these risks. This article will provide an overview of the legal basis and requirements for the ERA of GMO-containing medicinal products in the context of marketing authorisation in the EU and clinical trials in Germany. Furthermore, the scientific principles and methodology that generally need to be followed when preparing an ERA for GMOs are discussed.

  9. Attitudes towards the use of genetically modified animals in research.

    PubMed

    Schuppli, Catherine A; Weary, Daniel M

    2010-11-01

    Here we provide the first experimental evidence that public concerns about the use of animals in research are accentuated when genetically modified (GM) animals are used. Using an online survey, we probed participant views on two uses of pigs as research animals (to reduce agricultural pollution or to improve organ transplant success in humans) with and without GM. We surveyed 327 animal technicians, researchers, advocates, university students and others. In both scenarios and across demographics, support dropped off when the research required the use of GM pigs or GM corn. For example, 66% of participants supported using pigs to reduce phosphorus pollution, but this declined to 49% when the pigs were fed GM corn and to 20% when the research required the creation of a new GM line of pigs. Those involved in animal research were more consistently supportive compared to those who were not or those who were vegetarians.

  10. Genetically modified mosquito: the Malaysian public engagement experience.

    PubMed

    Subramaniam, T S Saraswathy; Lee, Han Lim; Ahmad, Nazni Wasi; Murad, Shahnaz

    2012-11-01

    On December 21, 2010, 6000 genetically modified (GM) mosquitoes were released in an uninhabited forest in Malaysia. The purpose of the deliberate release was a limited “marked release and recapture” (MRR) experiment, a standard ecological method in entomology, to evaluate under field conditions, the flight distance and longevity of the sterile male Aedes aegypti strain OX513A(My1), a GM strain. As with any other GM technologies, the release was received with mixed responses. As the scientific community debate over the public engagement strategies for similar GM releases, dengue incidence continues to rise with a heavy toll on morbidity, mortality and healthcare budgets. Meanwhile the wild female Aedes aegypti continues to breed offspring, surviving and evading conventional interventions for vector control.

  11. Exploring the structure of attitudes toward genetically modified food.

    PubMed

    Poortinga, Wouter; Pidgeon, Nick F

    2006-12-01

    Although it is often thought that the British public is opposed to genetically modified (GM) food, recent qualitative work suggests that most people are ambivalent about GM food and crops. In this article we explore the structure of attitudes in order to examine whether attitudinal ambivalence can be captured by more quantitative methods. Based on the finding that the perceived risks and benefits of GM food can be treated as independent dimensions, we propose a four-way typology of attitudes, consisting of a positive, negative, indifferent, and ambivalent group. This study showed that the differences between the four groups could best be described by three main dimensions: (1) a general evaluative dimension, (2) an involvement dimension, and (3) an attitudinal certainty dimension. While these different attitudinal dimensions have generally been studied in isolation, we argue that they should be studied collectively.

  12. Biological and biomedical aspects of genetically modified food.

    PubMed

    Celec, Peter; Kukucková, Martina; Renczésová, Veronika; Natarajan, Satheesh; Pálffy, Roland; Gardlík, Roman; Hodosy, Július; Behuliak, Michal; Vlková, Barbora; Minárik, Gabriel; Szemes, Tomás; Stuchlík, Stanislav; Turna, Ján

    2005-12-01

    Genetically modified (GM) foods are the product of one of the most progressive fields of science-biotechnology. There are major concerns about GM foods in the public; some of them are reasonable, some of them are not. Biomedical risks of GM foods include problems regarding the potential allergenicity, horizontal gene transfer, but environmental side effects on biodiversity must also be recognized. Numerous methods have been developed to assess the potential risk of every GM food type. Benefits of the first generation of GM foods were oriented towards the production process and companies, the second generation of GM foods offers, on contrary, various advantages and added value for the consumer. This includes improved nutritional composition or even therapeutic effects. Recombinant probiotics and the principle of alternative gene therapy represent the latest approach of using GM organisms for biomedical applications. This article tries to summarize and to explain the problematic topic of GM food.

  13. Risk assessment of genetically modified crops for nutrition and health.

    PubMed

    Magaña-Gómez, Javier A; de la Barca, Ana M Calderón

    2009-01-01

    The risk assessment of genetically modified (GM) crops for human nutrition and health has not been systematic. Evaluations for each GM crop or trait have been conducted using different feeding periods, animal models, and parameters. The most common result is that GM and conventional sources induce similar nutritional performance and growth in animals. However, adverse microscopic and molecular effects of some GM foods in different organs or tissues have been reported. Diversity among the methods and results of the risk assessments reflects the complexity of the subject. While there are currently no standardized methods to evaluate the safety of GM foods, attempts towards harmonization are on the way. More scientific effort is necessary in order to build confidence in the evaluation and acceptance of GM foods.

  14. The state of genetically modified crop regulation in Canada

    PubMed Central

    Smyth, Stuart J

    2014-01-01

    Genetically modified (GM) crops were first commercialized in Canada in 1995 and the 2014 crop represents the 20th year of successful production. Prior to the first commercialization of GM crops, Canada reviewed its existing science-based regulatory framework and adapted the existing framework to allow for risk assessments on the new technology to be undertaken in a timely and efficient manner. The result has been the rapid and widespread adoption of GM varieties of canola, corn and soybeans. The first decade of GM crop production precipitated 2 landmark legal cases relating to patent infringement and economic liability, while the second decade witnessed increased political efforts to have GM crops labeled in Canada as well as significant challenges from the low level comingling of GM crops with non-GM commodities. This article reviews the 20 y of GM crop production in Canada from a social science perspective that includes intellectual property, consumer acceptance and low level presence. PMID:25437238

  15. Molecular characterization of genetically-modified crops: Challenges and strategies.

    PubMed

    Li, Rong; Quan, Sheng; Yan, Xiaofang; Biswas, Sukumar; Zhang, Dabing; Shi, Jianxin

    Molecular characterization lays a foundation for safety assessment and subsequent monitoring of genetically modified (GM) crops. Due to the target-specific nature, conventional polymerase chain reaction (PCR)-based methods cannot comprehensively detect unintended gene insertions, let alone unknown GM events. As more and more new developed GM crops including new plant breeding technology (NPBT) generated crops are in the pipeline for commercialization, alternative -omics approaches, particularly next generation sequencing, have been developed for molecular characterization of authorized or unauthorized GM (UGM) crops. This review summarizes first those methods, addresses their challenges, and discusses possible strategies for molecular characterization of engineered crops generated by NPBT, highlighting needs for a global information-sharing database and cost-effective, accurate and comprehensive molecular characterization approaches.

  16. DNA enrichment approaches to identify unauthorized genetically modified organisms (GMOs).

    PubMed

    Arulandhu, Alfred J; van Dijk, Jeroen P; Dobnik, David; Holst-Jensen, Arne; Shi, Jianxin; Zel, Jana; Kok, Esther J

    2016-07-01

    With the increased global production of different genetically modified (GM) plant varieties, chances increase that unauthorized GM organisms (UGMOs) may enter the food chain. At the same time, the detection of UGMOs is a challenging task because of the limited sequence information that will generally be available. PCR-based methods are available to detect and quantify known UGMOs in specific cases. If this approach is not feasible, DNA enrichment of the unknown adjacent sequences of known GMO elements is one way to detect the presence of UGMOs in a food or feed product. These enrichment approaches are also known as chromosome walking or gene walking (GW). In recent years, enrichment approaches have been coupled with next generation sequencing (NGS) analysis and implemented in, amongst others, the medical and microbiological fields. The present review will provide an overview of these approaches and an evaluation of their applicability in the identification of UGMOs in complex food or feed samples.

  17. Development of melting temperature-based SYBR Green I polymerase chain reaction methods for multiplex genetically modified organism detection.

    PubMed

    Hernández, Marta; Rodríguez-Lázaro, David; Esteve, Teresa; Prat, Salomé; Pla, Maria

    2003-12-15

    Commercialization of several genetically modified crops has been approved worldwide to date. Uniplex polymerase chain reaction (PCR)-based methods to identify these different insertion events have been developed, but their use in the analysis of all commercially available genetically modified organisms (GMOs) is becoming progressively insufficient. These methods require a large number of assays to detect all possible GMOs present in the sample and thereby the development of multiplex PCR systems using combined probes and primers targeted to sequences specific to various GMOs is needed for detection of this increasing number of GMOs. Here we report on the development of a multiplex real-time PCR suitable for multiple GMO identification, based on the intercalating dye SYBR Green I and the analysis of the melting curves of the amplified products. Using this method, different amplification products specific for Maximizer 176, Bt11, MON810, and GA21 maize and for GTS 40-3-2 soybean were obtained and identified by their specific Tm. We have combined amplification of these products in a number of multiplex reactions and show the suitability of the methods for identification of GMOs with a sensitivity of 0.1% in duplex reactions. The described methods offer an economic and simple alternative to real-time PCR systems based on sequence-specific probes (i.e., TaqMan chemistry). These methods can be used as selection tests and further optimized for uniplex GMO quantification.

  18. Genetic Architecture of Maize Kernel Quality in the Nested Association Mapping (NAM) Population

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many studies have been conducted to identify genes (quantitative trait loci; QTL) underlying kernel quality traits. However, these studies were limited to analyzing two parents at once and often resulted in low resolution mapping of QTL. The maize nested association mapping (NAM) population is a r...

  19. Genetic diversity of Talaromyces species isolated from maize in North America

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Talaromyces species isolated from maize in the U.S., primarily between 1970 and 2014 were grown up from lyophilized storage to identify potential seed endophytes. These isolates had been predominantly identified as Penicillium funiculosum following the taxonomic system of Raper & Thom (1949), althou...

  20. Genetic architecture of maize kernel composition in the nested association mapping and inbred association panels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The maize kernel plays a critical role in feeding humans and livestock around the world and in a wide array of industrial applications. An understanding of the regulation of kernel starch, protein, and oil is needed in order to manipulate composition to meet future needs. We conducted quantitative...

  1. Acceptance of genetically modified foods: the relation between technology and evaluation.

    PubMed

    Tenbült, Petra; De Vries, Nanne K; van Breukelen, Gerard; Dreezens, Ellen; Martijn, Carolien

    2008-07-01

    This study investigates why consumers accept different genetically modified food products to different extents. The study shows that whether food products are genetically modified or not and whether they are processed or not are the two important features that affect the acceptance of food products and their evaluation (in terms of perceived healthiness, naturalness, necessity and tastiness). The extent to which these evaluation attributes and acceptance of a product are affected by genetic modification or processing depends on whether the product is negatively affected by the other technology: Any technological change to a 'natural' product (when nonprocessed products are genetically modified or when non-genetically modified products are processed) affect evaluation and acceptance stronger than a change to an technologically adapted product (when processed products are also genetically modified or vice versa). Furthermore, evaluation attributes appear to mediate the effects of genetic modification and processing on acceptance.

  2. [Detection of genetically modified organisms obtained from food samples ].

    PubMed

    Monma, Kimio; Araki, Rie; Ichikawa, Hisatsugu; Sato, Masaki; Uno, Naomichi; Sato, Kazue; Tobe, Takashi; Kuribara, Hideo; Matsuoka, Takeshi; Hino, Akihiro; Saito, Kazuo

    2004-08-01

    Genetially modified organisms (GMOs) were explored in food samples obtained from November 2000 to March 2003 in the Tokyo area by using PCR and real-time PCR techniques. The existence of Roundup Ready Soybean (RRS) was surveyed in processed foods derived from soybeans, such as tofu, boiled soybean, kinako, nama-age, abura-age, natto, miso, soymilk and yuba. RRS was detected in 3 of 37 tofu, 2 of 3 nama-age, 2 of 3 yuba and 3 of 3 abura-age samples. The CBH351 in 70 processed corn foods, NewLeaf Plus and NewLeaf Y in 50 processed potato foods, and 55-1 papaya in 16 papayas were surveyed. These GMOs were not detected among the samples. Qualitative and quantitative analyses of RRS and genetically modified (GM) corn were performed in soybean, corn and semi-processed corn products such as corn meal, corn flour and corn grits. RRS was detected in 42 of 178 soybean samples, and the amount of RRS in RRS-positive samples was determined. The content was in the range of 0.1-1.4% in identity-preserved soybeans (non-GMO), and 49.8-78.8% in non-segregated soybeans. On the other hand, GM corns were detected in 8 of 26 samples. The amount of GM corn in GM corn-positive samples was in the range of 0.1-2.0%.

  3. Molecular Evolution and Genetic Variation of G2-Like Transcription Factor Genes in Maize

    PubMed Central

    Han, Guomin; Zhou, Lingyan; Ali, Asif; Zhu, Suwen; Li, Xiaoyu

    2016-01-01

    The productivity of maize (Zea mays L.) depends on the development of chloroplasts, and G2-like transcription factors play a central role in regulating chloroplast development. In this study, we identified 59 G2-like genes in the B73 maize genome and systematically analyzed these genes at the molecular and evolutionary levels. Based on gene structure character, motif compositions and phylogenetic analysis, maize G2-like genes (ZmG1- ZmG59) were divided into seven groups (I-VII). By synteny analysis, 18 collinear gene pairs and strongly conserved microsyntny among regions hosting G2-like genes across maize and sorghum were found. Here, we showed that the vast majority of ZmG gene duplications resulted from whole genome duplication events rather than tandem duplications. After gene duplication events, some ZmG genes were silenced. The functions of G2-like genes were multifarious and most genes that are expressed in green tissues may relate to maize photosynthesis. The qRT-PCR showed that the expression of these genes was sensitive to low temperature and drought. Furthermore, we analyzed differences of ZmGs specific to cultivars in temperate and tropical regions at the population level. Interestingly, the single nucleotide polymorphism (SNP) analysis revealed that nucleotide polymorphism associated with different temperature zones. Above all, G2-like genes were highly conserved during evolution, but polymorphism could be caused due to a different geographical location. Moreover, G2-like genes might be related to cold and drought stresses. PMID:27560803

  4. Genetically modified foods, science, consumers and the media.

    PubMed

    Rowland, I R

    2002-02-01

    In contrast to the situation in the USA, where a wide range of genetically modified (GM) foods is available, in Europe very few GM products have been approved for marketing as foods, and there is widespread public concern about their safety and environmental impact. The marketing of a GM crop for food use in Europe falls under the EC novel foods regulations, and applications require the submission of an extensive dossier of information. The safety evaluation of GM foods presents considerable problems both in the conduct and interpretation of experimental studies, because conventional toxicity tests used in the evaluation of simple chemicals may not be appropriate for whole foods. To rationalise the safety evaluation process and to circumvent the difficulties in toxicological assessment of food materials, the concept of substantial equivalence has been developed. The concept is that if it can be demonstrated that the novel food is essentially similar to its conventional counterpart in terms of critical nutritional or anutritional components, then it is likely to be no more or less toxic than the latter. The possible introduction of unintended effects by the genetic modification process is particularly problematic for the safety evaluation process. The new genomic and post-genomic techniques are potentially valuable in the safety evaluation of GM foods, although they are as yet in their infancy.

  5. The MaizeGDB Genome Browser

    Technology Transfer Automated Retrieval System (TEKTRAN)

    MaizeGDB (http://www.maizegdb.org) is the community database for maize genetics and genomics. As part of an effort to develop MaizeGDB as a more sequence-centric resource, we implemented a genome browser based on information we gathered by surveying the community of maize geneticists. Based on commu...

  6. Prospects for genetically modified non-human primate models, including the common marmoset.

    PubMed

    Sasaki, Erika

    2015-04-01

    Genetically modified mice have contributed much to studies in the life sciences. In some research fields, however, mouse models are insufficient for analyzing the molecular mechanisms of pathology or as disease models. Often, genetically modified non-human primate (NHP) models are desired, as they are more similar to human physiology, morphology, and anatomy. Recent progress in studies of the reproductive biology in NHPs has enabled the introduction of exogenous genes into NHP genomes or the alteration of endogenous NHP genes. This review summarizes recent progress in the production of genetically modified NHPs, including the common marmoset, and future perspectives for realizing genetically modified NHP models for use in life sciences research.

  7. A large maize (Zea Mays L.) SNP genotyping array: development and germplasm genotyping, and genetic mapping to compare with the B73 reference genome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    SNP genotyping arrays have been useful for many applications that require a large number of molecular markers such as high-density genetic mapping, genome-wide association studies (GWAS), and genomic selection for accelerated breeding. We report the establishment of a large SNP array for maize and i...

  8. Genetic basis and detection of unintended effects in genetically modified crop plants.

    PubMed

    Ladics, Gregory S; Bartholomaeus, Andrew; Bregitzer, Phil; Doerrer, Nancy G; Gray, Alan; Holzhauser, Thomas; Jordan, Mark; Keese, Paul; Kok, Esther; Macdonald, Phil; Parrott, Wayne; Privalle, Laura; Raybould, Alan; Rhee, Seung Yon; Rice, Elena; Romeis, Jörg; Vaughn, Justin; Wal, Jean-Michel; Glenn, Kevin

    2015-08-01

    In January 2014, an international meeting sponsored by the International Life Sciences Institute/Health and Environmental Sciences Institute and the Canadian Food Inspection Agency titled "Genetic Basis of Unintended Effects in Modified Plants" was held in Ottawa, Canada, bringing together over 75 scientists from academia, government, and the agro-biotech industry. The objectives of the meeting were to explore current knowledge and identify areas requiring further study on unintended effects in plants and to discuss how this information can inform and improve genetically modified (GM) crop risk assessments. The meeting featured presentations on the molecular basis of plant genome variability in general, unintended changes at the molecular and phenotypic levels, and the development and use of hypothesis-driven evaluations of unintended effects in assessing conventional and GM crops. The development and role of emerging "omics" technologies in the assessment of unintended effects was also discussed. Several themes recurred in a number of talks; for example, a common observation was that no system for genetic modification, including conventional methods of plant breeding, is without unintended effects. Another common observation was that "unintended" does not necessarily mean "harmful". This paper summarizes key points from the information presented at the meeting to provide readers with current viewpoints on these topics.

  9. Genetic Architecture of Maize Kernel Composition in the Nested Association Mapping and Inbred Association Panels1[W

    PubMed Central

    Cook, Jason P.; McMullen, Michael D.; Holland, James B.; Tian, Feng; Bradbury, Peter; Ross-Ibarra, Jeffrey; Buckler, Edward S.; Flint-Garcia, Sherry A.

    2012-01-01

    The maize (Zea mays) kernel plays a critical role in feeding humans and livestock around the world and in a wide array of industrial applications. An understanding of the regulation of kernel starch, protein, and oil is needed in order to manipulate composition to meet future needs. We conducted joint-linkage quantitative trait locus mapping and genome-wide association studies (GWAS) for kernel starch, protein, and oil in the maize nested association mapping population, composed of 25 recombinant inbred line families derived from diverse inbred lines. Joint-linkage mapping revealed that the genetic architecture of kernel composition traits is controlled by 21–26 quantitative trait loci. Numerous GWAS associations were detected, including several oil and starch associations in acyl-CoA:diacylglycerol acyltransferase1-2, a gene that regulates oil composition and quantity. Results from nested association mapping were verified in a 282 inbred association panel using both GWAS and candidate gene association approaches. We identified many beneficial alleles that will be useful for improving kernel starch, protein, and oil content. PMID:22135431

  10. Genetic analysis of fumonisin production and virulence of Gibberella fujikuroi mating population A (Fusarium moniliforme) on maize (Zea mays) seedlings.

    PubMed Central

    Desjardins, A E; Plattner, R D; Nelsen, T C; Leslie, J F

    1995-01-01

    The phytopathogenic fungus Gibberella fujikuroi mating population A (anamorph, Fusarium moniliforme) produces fumonisins, which are toxic to a wide range of plant and animal species. Previous studies of field strains have identified a genetic locus, designated fum1, that can determine whether fumonisins are produced. To test the relationship between fumonisin production and virulence on maize seedlings, a cross between a fum1+ field strain that had a high degree of virulence and a fum1- field strain that had a low degree of virulence was made, and ascospore progeny were scored for these traits. Although a range of virulence levels was recovered among the progeny, high levels of virulence were associated with production of fumonisins, and highly virulent, fumonisin-nonproducing progeny were not obtained. A survey of field strains did identify a rare fumonisin-nonproducing strain that was quite high in virulence. Also, the addition of purified fumonisin B1 to virulence assays did not replicate all of the seedling blight symptoms obtained with autoclaved culture material containing fumonisin. These results support the hypothesis that fumonisin plays a role in virulence but also indicate that fumonisin production is not necessary or sufficient for virulence on maize seedlings. PMID:7887628

  11. Development of an event-specific hydrolysis probe quantitative real-time polymerase chain reaction assay for Embrapa 5.1 genetically modified common bean (Phaseolus vulgaris).

    PubMed

    Treml, Diana; Venturelli, Gustavo L; Brod, Fábio C A; Faria, Josias C; Arisi, Ana C M

    2014-12-10

    A genetically modified (GM) common bean event, namely Embrapa 5.1, resistant to the bean golden mosaic virus (BGMV), was approved for commercialization in Brazil. Brazilian regulation for genetically modified organism (GMO) labeling requires that any food containing more than 1% GMO be labeled. The event-specific polymerase chain reaction (PCR) method has been the primary trend for GMO identification and quantitation because of its high specificity based on the flanking sequence. This work reports the development of an event-specific assay, named FGM, for Embrapa 5.1 detection and quantitation by use of SYBR Green or hydrolysis probe. The FGM assay specificity was tested for Embrapa 2.3 event (a noncommercial GM common bean also resistant to BGMV), 46 non-GM common bean varieties, and other crop species including maize, GM maize, soybean, and GM soybean. The FGM assay showed high specificity to detect the Embrapa 5.1 event. Standard curves for the FGM assay presented a mean efficiency of 95% and a limit of detection (LOD) of 100 genome copies in the presence of background DNA. The primers and probe developed are suitable for the detection and quantitation of Embrapa 5.1.

  12. Simultaneous detection of genetically modified organisms by multiplex ligation-dependent genome amplification and capillary gel electrophoresis with laser-induced fluorescence.

    PubMed

    García-Cañas, Virginia; Mondello, Monica; Cifuentes, Alejandro

    2010-07-01

    In this work, an innovative method useful to simultaneously analyze multiple genetically modified organisms is described. The developed method consists in the combination of multiplex ligation-dependent genome dependent amplification (MLGA) with CGE and LIF detection using bare-fused silica capillaries. The MLGA process is based on oligonucleotide constructs, formed by a universal sequence (vector) and long specific oligonucleotides (selectors) that facilitate the circularization of specific DNA target regions. Subsequently, the circularized target sequences are simultaneously amplified with the same couple of primers and analyzed by CGE-LIF using a bare-fused silica capillary and a run electrolyte containing 2-hydroxyethyl cellulose acting as both sieving matrix and dynamic capillary coating. CGE-LIF is shown to be very useful and informative for optimizing MLGA parameters such as annealing temperature, number of ligation cycles, and selector probes concentration. We demonstrate the specificity of the method in detecting the presence of transgenic DNA in certified reference and raw commercial samples. The method developed is sensitive and allows the simultaneous detection in a single run of percentages of transgenic maize as low as 1% of GA21, 1% of MON863, and 1% of MON810 in maize samples with signal-to-noise ratios for the corresponding DNA peaks of 15, 12, and 26, respectively. These results demonstrate, to our knowledge for the first time, the great possibilities of MLGA techniques for genetically modified organisms analysis.

  13. A genetic test of bioactive gibberellins as regulators of heterosis in maize.

    PubMed

    Auger, D L; Peters, E M; Birchler, J A

    2005-01-01

    This study tested the hypothesis that gibberellin levels were responsible for the superior growth habit of hybrids (i.e., heterosis). If this were true, plants reduced in their capacity to produce gibberellin, such as maize plants homozygous for dwarf1 (d1), should display a lesser heterotic response. The d1 mutation was introgressed into two inbred lines of maize, B73 and Mo17, for seven generations. Plants segregating for the dwarf phenotype were produced both by self-fertilizing the introgressed inbred lines and by making reciprocal crosses between them to produce hybrids. Measurements were made of several physical traits. The results indicated that the hybrid dwarf plants experienced no loss of heterosis relative to their normal siblings. These results exclude the possibility that modulation of bioactive gibberellins is a major underlying basis of the heterotic response.

  14. Genetic Variation in Fusarium Section Liseola from No-Till Maize in Argentina†

    PubMed Central

    Chulze, S. N.; Ramirez, M. L.; Torres, A.; Leslie, J. F.

    2000-01-01

    Strains of Fusarium species belonging to section Liseola cause stalk and ear rot of maize and produce important mycotoxins, such as fumonisins. We isolated two species, Fusarium verticillioides (Gibberella fujikuroi mating population A) and Fusarium proliferatum (G. fujikuroi mating population D) from maize cultivated under no-till conditions at five locations in the Córdoba province of Argentina. We determined the effective population number for mating population A (Ne) and found that the Ne for mating type was 89% of the count (total population) and that the Ne for male or hermaphrodite status was 36%. Thus, the number of strains that can function as the female parent limits Ne, and sexual reproduction needs to occur only once every 54 to 220 asexual generations to maintain this level of sexual fertility. Our results indicate that the fungal populations isolated from no-till maize are similar to those recovered from maize managed with conventional tillage. We placed 36 strains from mating population A into 28 vegetative compatibility groups (VCGs). Of the 13 strains belonging to five multimember VCGs, only 2 isolates belonging to one VCG were clones based on amplified fragment length polymorphism (AFLP) fingerprints. Members of the other four multimember VCGs had an average similarity index of 0.89, and members of one VCG were no more closely related to other members of the same VCG than they were to other members of the population as a whole. This finding suggests that the common assumption that strains in the same VCG are either clonal or very closely related needs to be examined in more detail. The variability observed with AFLPs and VCGs suggests that sexual reproduction may occur more frequently than estimated by Ne. PMID:11097907

  15. Genetic variation in Fusarium section Liseola from no-till maize in Argentina.

    PubMed

    Chulze, S N; Ramirez, M L; Torres, A; Leslie, J F

    2000-12-01

    Strains of Fusarium species belonging to section Liseola cause stalk and ear rot of maize and produce important mycotoxins, such as fumonisins. We isolated two species, Fusarium verticillioides (Gibberella fujikuroi mating population A) and Fusarium proliferatum (G. fujikuroi mating population D) from maize cultivated under no-till conditions at five locations in the Córdoba province of Argentina. We determined the effective population number for mating population A (N(e)) and found that the N(e) for mating type was 89% of the count (total population) and that the N(e) for male or hermaphrodite status was 36%. Thus, the number of strains that can function as the female parent limits N(e), and sexual reproduction needs to occur only once every 54 to 220 asexual generations to maintain this level of sexual fertility. Our results indicate that the fungal populations isolated from no-till maize are similar to those recovered from maize managed with conventional tillage. We placed 36 strains from mating population A into 28 vegetative compatibility groups (VCGs). Of the 13 strains belonging to five multimember VCGs, only 2 isolates belonging to one VCG were clones based on amplified fragment length polymorphism (AFLP) fingerprints. Members of the other four multimember VCGs had an average similarity index of 0.89, and members of one VCG were no more closely related to other members of the same VCG than they were to other members of the population as a whole. This finding suggests that the common assumption that strains in the same VCG are either clonal or very closely related needs to be examined in more detail. The variability observed with AFLPs and VCGs suggests that sexual reproduction may occur more frequently than estimated by N(e).

  16. Invertebrate responses to the management of genetically modified herbicide-tolerant and conventional spring crops. I. Soil-surface-active invertebrates.

    PubMed Central

    Brooks, D R; Bohan, D A; Champion, G T; Haughton, A J; Hawes, C; Heard, M S; Clark, S J; Dewar, A M; Firbank, L G; Perry, J N; Rothery, P; Scott, R J; Woiwod, I P; Birchall, C; Skellern, M P; Walker, J H; Baker, P; Bell, D; Browne, E L; Dewar, A J G; Fairfax, C M; Garner, B H; Haylock, L A; Horne, S L; Hulmes, S E; Mason, N S; Norton, L R; Nuttall, P; Randle, Z; Rossall, M J; Sands, R J N; Singer, E J; Walker, M J

    2003-01-01

    The effects of herbicide management of genetically modified herbicide-tolerant (GMHT) beet, maize and spring oilseed rape on the abundance and diversity of soil-surface-active invertebrates were assessed. Most effects did not differ between years, environmental zones or initial seedbanks or between sugar and fodder beet. This suggests that the results may be treated as generally applicable to agricultural situations throughout the UK for these crops. The direction of the effects was evenly balanced between increases and decreases in counts in the GMHT compared with the conventional treatment. Most effects involving a greater capture in the GMHT treatments occurred in maize, whereas most effects involving a smaller capture were in beet and spring oilseed rape. Differences between GMHT and conventional crop herbicide management had a significant effect on the capture of most surface-active invertebrate species and higher taxa tested in at least one crop, and these differences reflected the phenology and ecology of the invertebrates. Counts of carabids that feed on weed seeds were smaller in GMHT beet and spring oilseed rape but larger in GMHT maize. In contrast, collembolan detritivore counts were significantly larger under GMHT crop management. PMID:14561318

  17. A design for the control of apoptosis in genetically modified Saccharomyces cerevisiae.

    PubMed

    Nishida, Nao; Noguchi, Misa; Kuroda, Kouichi; Ueda, Mitsuyoshi

    2014-01-01

    We have engineered a system that holds potential for use as a safety switch in genetically modified yeasts. Human apoptotic factor BAX (no homolog in yeast), under the control of the FBP1 (gluconeogenesis enzyme) promoter, was conditionally expressed to induce yeast cell apoptosis after glucose depletion. Such systems might prove useful for the safe use of genetically modified organisms.

  18. Environmental impacts of genetically modified plants: A review.

    PubMed

    Tsatsakis, Aristidis M; Nawaz, Muhammad Amjad; Kouretas, Demetrios; Balias, Georgios; Savolainen, Kai; Tutelyan, Victor A; Golokhvast, Kirill S; Lee, Jeong Dong; Yang, Seung Hwan; Chung, Gyuhwa

    2017-03-27

    Powerful scientific techniques have caused dramatic expansion of genetically modified crops leading to altered agricultural practices posing direct and indirect environmental implications. Despite the enhanced yield potential, risks and biosafety concerns associated with such GM crops are the fundamental issues to be addressed. An increasing interest can be noted among the researchers and policy makers in exploring unintended effects of transgenes associated with gene flow, flow of naked DNA, weediness and chemical toxicity. The current state of knowledge reveals that GM crops impart damaging impacts on the environment such as modification in crop pervasiveness or invasiveness, the emergence of herbicide and insecticide tolerance, transgene stacking and disturbed biodiversity, but these impacts require a more in-depth view and critical research so as to unveil further facts. Most of the reviewed scientific resources provide similar conclusions and currently there is an insufficient amount of data available and up until today, the consumption of GM plant products are safe for consumption to a greater extent with few exceptions. This paper updates the undesirable impacts of GM crops and their products on target and non-target species and attempts to shed light on the emerging challenges and threats associated with it. Underpinning research also realizes the influence of GM crops on a disturbance in biodiversity, development of resistance and evolution slightly resembles with the effects of non-GM cultivation. Future prospects are also discussed.

  19. New qualitative detection methods of genetically modified potatoes.

    PubMed

    Watanabe, Takahiro; Kuribara, Hideo; Mishima, Takashi; Kikuchi, Hiroyuki; Kodama, Takashi; Futo, Satoshi; Kasama, Kikuko; Toyota, Akie; Nouno, Masanori; Saita, Ayako; Takahashi, Kunihiko; Hino, Akihiro; Akiyama, Hiroshi; Maitani, Tamio; Kubo, Misao

    2004-09-01

    In Japan, 8 lines of genetically modified (GM) potato (2 lines of NewLeaf potato; NL, 3 lines of NewLeaf Plus potato; NLP, and 3 lines of NewLeaf Y potato; NLY) have already been authorized as safe for use in foods and feeds. We have developed polymerase chain reaction (PCR) methods for the qualitative detection of the GM potatoes for the screening and the identification of NL, NLP and NLY. The gene encoding uridine diphosphate (UDP)-glucose pyrophosphorylase (UGPase) was used as a taxon specific gene. We designed the primer pair to detect the cryIIIA genes as a screening method for GM potatoes because the gene should be inserted in all 8 lines of the GM potatoes. For identification of NL, NLP and NLY, we further designed three specific primer pairs for the different recombinant DNAs (r-DNA) specifically introduced into NL, NLP, or NLY. In addition, to identify the 3 lines of NLY that have been introduced with the same r-DNA, the three line-specific primer pairs for the border sequence between the r-DNA and genomic DNA of NLY 3 lines were designed. Six lines of GM potato used as the test material were specifically identified using the each primer pair under the same PCR condition. The detection limits of all the GM potatoes should be approximately 0.1%. Furthermore, the specificity and reproducibility of the methods were confirmed in a six-laboratory collaborative study.

  20. Detection methods and performance criteria for genetically modified organisms.

    PubMed

    Bertheau, Yves; Diolez, Annick; Kobilinsky, André; Magin, Kimberly

    2002-01-01

    Detection methods for genetically modified organisms (GMOs) are necessary for many applications, from seed purity assessment to compliance of food labeling in several countries. Numerous analytical methods are currently used or under development to support these needs. The currently used methods are bioassays and protein- and DNA-based detection protocols. To avoid discrepancy of results between such largely different methods and, for instance, the potential resulting legal actions, compatibility of the methods is urgently needed. Performance criteria of methods allow evaluation against a common standard. The more-common performance criteria for detection methods are precision, accuracy, sensitivity, and specificity, which together specifically address other terms used to describe the performance of a method, such as applicability, selectivity, calibration, trueness, precision, recovery, operating range, limit of quantitation, limit of detection, and ruggedness. Performance criteria should provide objective tools to accept or reject specific methods, to validate them, to ensure compatibility between validated methods, and be used on a routine basis to reject data outside an acceptable range of variability. When selecting a method of detection, it is also important to consider its applicability, its field of applications, and its limitations, by including factors such as its ability to detect the target analyte in a given matrix, the duration of the analyses, its cost effectiveness, and the necessary sample sizes for testing. Thus, the current GMO detection methods should be evaluated against a common set of performance criteria.

  1. Electrochemiluminescence-PCR detection of genetically modified organisms

    NASA Astrophysics Data System (ADS)

    Liu, Jinfeng; Xing, Da; Shen, Xingyan; Zhu, Debin

    2005-01-01

    The detection methods for genetically modified (GM) components in foods have been developed recently. But many of them are complicated and time-consuming; some of them need to use the carcinogenic substance, and can"t avoid false-positive results. In this study, an electrochemiluminescence polymerase chain reaction (ECL-PCR) method for detection GM tobaccos is proposed. The Cauliflower mosaic virus 35S (CaMV35S) promoter was amplified by PCR, Then hybridized with a Ru(bpy)32+ (TBR)-labeled and a biotinylated probe. The hybridization products were captured onto streptavidin-coated paramagnetic beads, and detected by measuring the electrochemiluminescence (ECL) signal of the TBR label. Whether the tobaccos contain GM components was discriminated by detecting the ECL signal of CaMV35S promoter. The experiment results show that the detection limit for CaMV35S promoter is 100 fmol, and the GM components can be clearly identified in GM tobaccos. The ECL-PCR method provide a new means in GMOs detection due to its safety, simplicity and high efficiency.

  2. Stakeholders' attitude to genetically modified foods and medicine.

    PubMed

    Amin, Latifah; Jahi, Jamaluddin Md; Nor, Abd Rahim Md

    2013-01-01

    Public acceptance of genetically modified (GM) foods has to be adequately addressed in order for their potential economic and social benefits to be realized. The objective of this paper is to assess the attitude of the Malaysian public toward GM foods (GM soybean and GM palm oil) and GM medicine (GM insulin). A survey was carried out using self-constructed multidimensional instrument measuring attitudes towards GM products. The respondents (n = 1017) were stratified according to stakeholders' groups in the Klang Valley region. Results of the survey show that the overall attitude of the Malaysian stakeholders towards GM products was cautious. Although they acknowledged the presence of moderate perceived benefits associated with GM products surveyed and were moderately encouraging of them, they were also moderately concerned about the risks and moral aspects of the three GM products as well as moderately accepting the risks. Attitudes towards GM products among the stakeholders were found to vary not according to the type of all GM applications but rather depend on the intricate relationships between the attitudinal factors and the type of gene transfers involved. Analyses of variance showed significant differences in the six dimensions of attitude towards GM products across stakeholders' groups.

  3. Determinants of Public Attitudes to Genetically Modified Salmon

    PubMed Central

    Amin, Latifah; Azad, Md. Abul Kalam; Gausmian, Mohd Hanafy; Zulkifli, Faizah

    2014-01-01

    The objective of this paper is to assess the attitude of Malaysian stakeholders to genetically modified (GM) salmon and to identify the factors that influence their acceptance of GM salmon using a structural equation model. A survey was carried out on 434 representatives from various stakeholder groups in the Klang Valley region of Malaysia. Public attitude towards GM salmon was measured using self-developed questionnaires with seven-point Likert scales. The findings of this study have confirmed that public attitudes towards GM salmon is a complex issue and should be seen as a multi-faceted process. The most important direct predictors for the encouragement of GM salmon are the specific application-linked perceptions about religious acceptability of GM salmon followed by perceived risks and benefits, familiarity, and general promise of modern biotechnology. Encouragement of GM salmon also involves the interplay among other factors such as general concerns of biotechnology, threatening the natural order of things, the need for labeling, the need for patenting, confidence in regulation, and societal values. The research findings can serve as a database that will be useful for understanding the social construct of public attitude towards GM foods in a developing country. PMID:24489695

  4. Commercializing genetically modified crops under EU regulations: objectives and barriers.

    PubMed

    Raybould, Alan; Poppy, Guy M

    2012-01-01

    Agriculture faces serious problems in feeding 9 billion people by 2050: production must be increased and ecosystem services maintained under conditions for growing crops that are predicted to worsen in many parts of the world. A proposed solution is sustainable intensification of agriculture, whereby yields are increased on land that is currently cultivated, so sparing land to deliver other ecosystem services. Genetically modified (GM) crops are already contributing to sustainable intensification through higher yields and lower environmental impacts, and have potential to deliver further significant improvements. Despite their widespread successful use elsewhere, the European Union (EU) has been slow to introduce GM crops: decisions on applications to import GM commodities are lengthy, and decision-making on applications to cultivate GM crops has virtually ceased. Delayed import approvals result in economic losses, particularly in the EU itself as a result of higher commodity prices. Failure to grant cultivation approvals costs EU farmers opportunities to reduce inputs, and results in loss of agricultural research and development from the EU to countries such as the United States and China. Delayed decision-making in the EU ostensibly results from scientific uncertainty about the effects of using GM crops; however, scientific uncertainty may be a means to justify a political decision to restrict cultivation of GM crops in the EU. The problems associated with delayed decision-making will not improve until there is clarity about the EU's agricultural policy objectives, and whether the use of GM crops will be permitted to contribute to achieving those objectives.

  5. Gene flow, invasiveness, and ecological impact of genetically modified crops.

    PubMed

    Warwick, Suzanne I; Beckie, Hugh J; Hall, Linda M

    2009-06-01

    The main environmental concerns about genetically modified (GM) crops are the potential weediness or invasiveness in the crop itself or in its wild or weedy relatives as a result of transgene movement. Here we briefly review evidence for pollen- and seed-mediated gene flow from GM crops to non-GM or other GM crops and to wild relatives. The report focuses on the effect of abiotic and biotic stress-tolerance traits on plant fitness and their potential to increase weedy or invasive tendencies. An evaluation of weediness and invasive traits that contribute to the success of agricultural weeds and invasive plants was of limited value in predicting the effect of biotic and abiotic stress-tolerance GM traits, suggesting context-specific evaluation rather than generalizations. Fitness data on herbicide, insect, and disease resistance, as well as cold-, drought-, and salinity-tolerance traits, are reviewed. We describe useful ecological models predicting the effects of gene flow and altered fitness in GM crops and wild/weedy relatives, as well as suitable mitigation measures. A better understanding of factors controlling population size, dynamics, and range limits in weedy volunteer GM crop and related host or target weed populations is necessary before the effect of biotic and abiotic stress-tolerance GM traits can be fully assessed.

  6. Examining consumer behavior toward genetically modified (GM) food in Britain.

    PubMed

    Spence, Alexa; Townsend, Ellen

    2006-06-01

    This study examined behavior toward genetically modified (GM) food in a British community-based sample. We used an equivalent gain task in which participants actually received the options they chose to encourage truthful responding. In conjunction with this, theory of planned behavior (TPB) components were evaluated so as to examine the relative importance of behavioral influences in this domain. Here, the TPB was extended to include additional components to measure self-identity, moral norms, and emotional involvement. Results indicated that the monetary amounts participants accepted in preference to GM food were significantly lower than those accepted in preference to non-GM food. However, the vast majority of participants were indifferent between GM and non-GM food options. All TPB components significantly predicted behavioral intentions to try GM food, with attitudes toward GM being the strongest predictor. Self-identity and emotional involvement were also found to be significant predictors of behavioral intentions but moral norms were not. In addition, behavioral intentions significantly predicted behavior; however, PBC did not. An additional measure of participants' propensity to respond in a socially desirable manner indicated that our results were not influenced by self-presentation issues, giving confidence to our findings. Overall, it appears that the majority of participants (74.5%) would purchase GM food at some price.

  7. Safety of foods derived from genetically modified plants.

    PubMed

    Thomas, John A

    2003-03-01

    Biopharmaceuticals have been available for clinical use for nearly three decades, but foods derived from agribiotechnology have been available for just under a decade. Controversy surrounding foods from genetically modified (GM) plants has focused primarily upon their allergenicity, with lesser concerns about antibiotic resistance genes. Concerns are related to possible environmental impacts on non-human species, including effects on non-target species (e.g., butterflies) and on the development of so-called "super weeds." Food allergies are no more prevalent in foods from GM plants than in conventional foods. Further, the use of antibiotics in the development of GM plants does not pose a significant risk to the human population. Foods from the current GM plant products have been shown not to pose any detrimental effects to humans, and, in fact, nutritionally enhanced products are being developed. GM foods are subjected globally to intense regulatory scrutiny, and extensive data have been provided consistently to regulatory agencies in the United States on a voluntary basis, with mandatory reporting of data soon to be in force. Existing environmental concerns appear to be unjustified on the basis of existing data and experience.

  8. Stakeholders' Attitude to Genetically Modified Foods and Medicine

    PubMed Central

    Md Jahi, Jamaluddin; Md Nor, Abd Rahim

    2013-01-01

    Public acceptance of genetically modified (GM) foods has to be adequately addressed in order for their potential economic and social benefits to be realized. The objective of this paper is to assess the attitude of the Malaysian public toward GM foods (GM soybean and GM palm oil) and GM medicine (GM insulin). A survey was carried out using self-constructed multidimensional instrument measuring attitudes towards GM products. The respondents (n = 1017) were stratified according to stakeholders' groups in the Klang Valley region. Results of the survey show that the overall attitude of the Malaysian stakeholders towards GM products was cautious. Although they acknowledged the presence of moderate perceived benefits associated with GM products surveyed and were moderately encouraging of them, they were also moderately concerned about the risks and moral aspects of the three GM products as well as moderately accepting the risks. Attitudes towards GM products among the stakeholders were found to vary not according to the type of all GM applications but rather depend on the intricate relationships between the attitudinal factors and the type of gene transfers involved. Analyses of variance showed significant differences in the six dimensions of attitude towards GM products across stakeholders' groups. PMID:24381520

  9. Determinants of public attitudes to genetically modified salmon.

    PubMed

    Amin, Latifah; Azad, Md Abul Kalam; Gausmian, Mohd Hanafy; Zulkifli, Faizah

    2014-01-01

    The objective of this paper is to assess the attitude of Malaysian stakeholders to genetically modified (GM) salmon and to identify the factors that influence their acceptance of GM salmon using a structural equation model. A survey was carried out on 434 representatives from various stakeholder groups in the Klang Valley region of Malaysia. Public attitude towards GM salmon was measured using self-developed questionnaires with seven-point Likert scales. The findings of this study have confirmed that public attitudes towards GM salmon is a complex issue and should be seen as a multi-faceted process. The most important direct predictors for the encouragement of GM salmon are the specific application-linked perceptions about religious acceptability of GM salmon followed by perceived risks and benefits, familiarity, and general promise of modern biotechnology. Encouragement of GM salmon also involves the interplay among other factors such as general concerns of biotechnology, threatening the natural order of things, the need for labeling, the need for patenting, confidence in regulation, and societal values. The research findings can serve as a database that will be useful for understanding the social construct of public attitude towards GM foods in a developing country.

  10. Regulatory control of genetically modified (GM) foods: likely developments.

    PubMed

    Schilter, Benoît; Constable, Anne

    2002-02-28

    The placing of genetically modified (GM) crops on the European market requires a regulatory approval supported by a thorough safety evaluation. This approach has been applied to all GM crops presently on the market. Despite this stringent process there has been an increasing public concern about the impact of GM foods on human health and the environment. In this context, regulatory control may develop in several directions. One response to the public concern is to strengthen the data requirements for the risk assessment process. Several avenues have been proposed. They include the application of technologies such as proteomics and metabolomics to assess unintended changes, and the development of predictive methods to evaluate allergenicity. Obligations for post-launch surveillance have appeared in regulations. Criteria are required to define when and why such approaches are necessary. Significant challenges including feasibility and validation of the methods, and safety relevance of the data generated will have to be addressed before any general application of these new approaches. Effective monitoring requires the ability to identify the presence of GM products and trace their origin. Traceability and labeling are therefore important developments in the GM food regulatory arena. Both require the development of reliable analytical detection tools.

  11. Biofilm control with natural and genetically-modified phages.

    PubMed

    Motlagh, Amir Mohaghegh; Bhattacharjee, Ananda Shankar; Goel, Ramesh

    2016-04-01

    Bacteriophages, as the most dominant and diverse entities in the universe, have the potential to be one of the most promising therapeutic agents. The emergence of multidrug-resistant bacteria and the antibiotic crisis in the last few decades have resulted in a renewed interest in phage therapy. Furthermore, bacteriophages, with the capacity to rapidly infect and overcome bacterial resistance, have demonstrated a sustainable approach against bacterial pathogens-particularly in biofilm. Biofilm, as complex microbial communities located at interphases embedded in a matrix of bacterial extracellular polysaccharide substances (EPS), is involved in health issues such as infections associated with the use of biomaterials and chronic infections by multidrug resistant bacteria, as well as industrial issues such as biofilm formation on stainless steel surfaces in food industry and membrane biofouling in water and wastewater treatment processes. In this paper, the most recent studies on the potential of phage therapy using natural and genetically-modified lytic phages and their associated enzymes in fighting biofilm development in various fields including engineering, industry, and medical applications are reviewed. Phage-mediated prevention approaches as an indirect phage therapy strategy are also explored in this review. In addition, the limitations of these approaches and suggestions to overcome these constraints are discussed to enhance the efficiency of phage therapy process. Finally, future perspectives and directions for further research towards a better understanding of phage therapy to control biofilm are recommended.

  12. Genetically modified crops: success, safety assessment, and public concern.

    PubMed

    Singh, Om V; Ghai, Shivani; Paul, Debarati; Jain, Rakesh K

    2006-08-01

    With the emergence of transgenic technologies, new ways to improve the agronomic performance of crops for food, feed, and processing applications have been devised. In addition, ability to express foreign genes using transgenic technologies has opened up options for producing large quantities of commercially important industrial or pharmaceutical products in plants. Despite this high adoption rate and future promises, there is a multitude of concerns about the impact of genetically modified (GM) crops on the environment. Potential contamination of the environment and food chains has prompted detailed consideration of how such crops and the molecules that they produce can be effectively isolated and contained. One of the reasonable steps after creating a transgenic plant is to evaluate its potential benefits and risks to the environment and these should be compared to those generated by traditional agricultural practices. The precautionary approach in risk management of GM plants may make it necessary to monitor significant wild and weed populations that might be affected by transgene escape. Effective risk assessment and monitoring mechanisms are the basic prerequisites of any legal framework to adequately address the risks and watch out for new risks. Several agencies in different countries monitor the release of GM organisms or frame guidelines for the appropriate application of recombinant organisms in agro-industries so as to assure the safe use of recombinant organisms and to achieve sound overall development. We feel that it is important to establish an internationally harmonized framework for the safe handling of recombinant DNA organisms within a few years.

  13. Consumer perception of genetically modified organisms and sources of information.

    PubMed

    Wunderlich, Shahla; Gatto, Kelsey A

    2015-11-01

    Genetically modified organisms (GMOs) have been available for commercial purchase since the 1990s, allowing producers to increase crop yields through bioengineering that creates herbicide-resistant and insect-resistant varieties. However, consumer knowledge about GMOs has not increased at the same rate as the adoption of GMO crops. Consumers worldwide are displaying limited understanding, misconceptions, and even unfamiliarity with GMO food products. Many consumers report that they receive information about GMO food products from the media, Internet, and other news sources. These sources may be less reliable than scientific experts whom consumers trust more to present the facts. Although many in the United States support mandatory GMO labeling (similar to current European standards), consumer awareness of current GMO labeling is low. A distinction must also be made between GMO familiarity and scientific understanding, because those who are more familiar with it tend to be more resistant to bioengineering, whereas those with higher scientific knowledge scores tend to have less negative attitudes toward GMOs. This brings to question the relation between scientific literacy, sources of information, and overall consumer knowledge and perception of GMO foods.

  14. Genetically modified crops for biomass increase. Genes and strategies.

    PubMed

    Rojas, Cristian Antonio; Hemerly, Adrianna Silva; Ferreira, Paulo Cavalcanti Gomes

    2010-01-01

    Genetically modified crops (GMCs) have been developed to accelerate the creation of new varieties with improved characteristics such as disease resistance, stress tolerance and higher quality composition. However, agriculture, without minimizing its role in food, feed and fiber source, has become important for the energy matrix of many countries. GMCs are also attractive systems that could fulfill the requirements for these new necessities. An increase of crop yields in an environmental friendly system is a new goal for plant biology research in the twenty-first century. In particular, biomass yield improvement is needed to render the use of biofuels economically feasible. In this context, research directed toward increasing biomass production has attracted much attention and a considerable effort is being made to reach new goals. Nonetheless, in some cases differentiated strategies are needed, as biomass improvement requires approaches other than those employed with traditional crops. This review summarizes the various approaches applied so far to modulate plant growth applying molecular biology-based strategies and increase biomass production, and it highlights several outstanding issues about the developmental constraints that must be addressed.

  15. Forecasting the Feasibility of Implementing Isolation Perimeters Between GM and non-GM Maize Fields Under Agricultural Conditions

    NASA Astrophysics Data System (ADS)

    Devos, Yann; Cougnon, Mathias; Thas, Olivier; De Clercq, Eva M.; Cordemans, Karl; Reheul, Dirk

    2008-10-01

    Although spatially isolating genetically modified (GM) maize fields from non-GM maize fields is a robust on-farm strategy to keep the adventitious presence of GM material in the harvests of neighboring non-GM maize fields due to cross-fertilizations below established labeling thresholds (and thus to ensure the spatial co-existence between maize cropping systems), the practical implementation of isolation perimeters attracted little research efforts. In this study, the feasibility of implementing isolation perimeters around GM maize fields is investigated. Using Geographic Information System datasets and Monte Carlo simulations, various scenarios differing in shares and spatial distributions of GM maize were tested for various isolation perimeters in six agricultural areas in Flanders. Factors that affect the feasibility of implementing isolation perimeters are discussed.

  16. Health Considerations Regarding Horizontal Transfer of Microbial Transgenes Present in Genetically Modified Crops

    PubMed Central

    Kleter, Gijs A.

    2005-01-01

    The potential effects of horizontal gene transfer on human health are an important item in the safety assessment of genetically modified organisms. Horizontal gene transfer from genetically modified crops to gut microflora most likely occurs with transgenes of microbial origin. The characteristics of microbial transgenes other than antibiotic-resistance genes in market-approved genetically modified crops are reviewed. These characteristics include the microbial source, natural function, function in genetically modified crops, natural prevalence, geographical distribution, similarity to other microbial genes, known horizontal transfer activity, selective conditions and environments for horizontally transferred genes, and potential contribution to pathogenicity and virulence in humans and animals. The assessment of this set of data for each of the microbial genes reviewed does not give rise to health concerns. We recommend including the above-mentioned items into the premarket safety assessment of genetically modified crops carrying transgenes other than those reviewed in the present study. PMID:16489267

  17. Genetically Modified Organisms and the Future Global Nutrient Supply: Part of the Solution or a New Problem?

    PubMed

    Phillips, Peter W B

    2016-01-01

    For almost a generation now, scientists and policy makers have enthusiastically advanced genetically modified (GM) crops as a solution to both global food security and, specifically, the micronutrient needs of the hidden hungry. While genetic modification offers the prospect of overcoming technological barriers to food security, the gap between the vision and reality remains large. This chapter examines the impact of GM crops at three levels. Undoubtedly, at the micro level, bio-fortification offers a real opportunity to enhance the availability of micronutrients. However, the inexorable 'research sieve' ruthlessly culls most technical candidates in the agri-food system. GM bio-fortified foods, such as Golden RiceTM, remain only a promise. At the meso level, GM crops have generated benefits for both producers and consumers who have adopted GM crops, but given that the technology has been differentially applied to maize, the average diet for the food insecure has become somewhat less balanced. Finally, while GM crops have increased yields and the global food supply, these have come at the cost of more complex and costly trade and market systems, which impair access and availability. In essence, while biotechnology offers some tantalizing technological prospects, the difficulties of getting the corresponding benefits to the most needy have dampened some of the enthusiasm.

  18. Health status and potential uptake of transgenic DNA by Japanese quail fed diets containing genetically modified plant ingredients over 10 generations.

    PubMed

    Korwin-Kossakowska, A; Sartowska, K; Tomczyk, G; Prusak, B; Sender, G

    2016-06-01

    The hypothesis assumes that feed containing GMOs affects animal health and results in the transgene product accumulating in the body. Therefore, the objective of the study was to evaluate the impact of genetically modified (GM) ingredients used in poultry diets on aspects of bird health status and accumulation of transgenic DNA in eggs, breast muscle and internal organs. A total of 10 generations of Japanese quail were fed three types of diets: group A - containing GM soya (Roundup Ready) and non-GM maize, group B - containing GM maize (MON810) and non-GM soya, and group C - containing non-GM soya and maize. Bird performance traits were monitored throughout the trial. In 17-week-old animals of each generation, health examination took place on birds from each group including post-mortem necropsy and histological organ evaluation. For the purpose of transgenic DNA detection, samples of selected important tissues were taken. A molecular screening method of PCR amplification was used. The analysis of the sectional examination of birds used in the current experiment did not indicate the existence of the pathological changes caused by pathogens, nutritional factors or of environmental nature. The histopathological changes occurred in all three dietary groups and there were no statistically significant differences between the groups. There was no transgene amplification - neither CaMV35S promoter sequence nor nos terminator sequence, in the samples derived from breast muscle, selected tissues and germinal discs (eggs). According to the obtained results, it was concluded that there was no negative effect of the use of GM soya or maize with regard to bird health status or to the presence of transgenic DNA in the final consumable product.

  19. The TIGR Maize Database.

    PubMed

    Chan, Agnes P; Pertea, Geo; Cheung, Foo; Lee, Dan; Zheng, Li; Whitelaw, Cathy; Pontaroli, Ana C; SanMiguel, Phillip; Yuan, Yinan; Bennetzen, Jeffrey; Barbazuk, William Brad; Quackenbush, John; Rabinowicz, Pablo D

    2006-01-01

    Maize is a staple crop of the grass family and also an excellent model for plant genetics. Owing to the large size and repetitiveness of its genome, we previously investigated two approaches to accelerate gene discovery and genome analysis in maize: methylation filtration and high C(0)t selection. These techniques allow the construction of gene-enriched genomic libraries by minimizing repeat sequences due to either their methylation status or their copy number, yielding a 7-fold enrichment in genic sequences relative to a random genomic library. Approximately 900,000 gene-enriched reads from maize were generated and clustered into Assembled Zea mays (AZM) sequences. Here we report the current AZM release, which consists of approximately 298 Mb representing 243,807 sequence assemblies and singletons. In order to provide a repository of publicly available maize genomic sequences, we have created the TIGR Maize Database (http://maize.tigr.org). In this resource, we have assembled and annotated the AZMs and used available sequenced markers to anchor AZMs to maize chromosomes. We have constructed a maize repeat database and generated draft sequence assemblies of 287 maize bacterial artificial chromosome (BAC) clone sequences, which we annotated along with 172 additional publicly available BAC clones. All sequences, assemblies and annotations are available at the project website via web interfaces and FTP downloads.

  20. [Methods of identification and assessment of safety of genetically modified microorganisms in manufacture food production].

    PubMed

    Khovaev, A A; Nesterenko, L N; Naroditskiĭ, B S

    2011-01-01

    Methods of identification of genetically modified microorganisms (GMM), used in manufacture food on control probes are presented. Results of microbiological and molecular and genetic analyses of food products and their components important in microbiological and genetic expert examination of GMM in foods are considered. Examination of biosafety of GMM are indicated.

  1. Genetically modified and wild soybeans: an immunologic comparison.

    PubMed

    Yum, Hye-Yung; Lee, Soo-Young; Lee, Kyung-Eun; Sohn, Myung-Hyun; Kim, Kyu-Earn

    2005-01-01

    Most traits introduced into genetically engineered crops result from the expression of new proteins. As the first step toward assessing the allergenic potential of genetically modified organism (GMO) food, immunologic and physicochemical characterizations are needed. We prepared crude extract from GMO soybeans, wild soybeans, curd, and soy milk and then performed sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). After acidification with HCl, the samples were separated to globulin and whey. To evaluate changes in protein composition, either the samples were heated or pepsin was added. Polymerase chain reaction with primer encoding the 35S-promotor and the 3-enol-pyruvyl-shikimat-5-phosphat-synthase gene were performed, respectively, to detect the GMO component. SDS-PAGE results showed definite protein bands at 80 kDa in GMO soybean, 50 kDa in wild soybean, and a similar distribution of protein bands was noticed below 40 kDa. It was difficult to observe protein distribution because of modifications that occurred during processing in soybean-processed products. After heating, proteins of GMO and wild soybeans showed similar distributions and no distinct bands were detected at 50 and 80 kDa. Although SDS-PAGE analyses of raw GMO and wild soybeans differed, the same protein bands of 68, 37, and 20 kDa were observed in the globulin fraction after acidification. After adding pepsin, 20- and 68-kDa bands were found preserved in GMO and wild soybeans. The polymerase chain reaction procedures with primers specific to GMO soybeans showed that GMO soybeans and some curd samples included a GMO component. The skin test results of 49 patients showed 13 positive results to wild soybeans and 8 positive results to GMO soybeans. One patient had a positive skin test result to GMO soybeans only. Sera from nine patients with positive skin tests to the crude extract and a positive capsulated allergen product test to the soybean antigen were used for the immunoblotting

  2. Application of a modified Haug and Lantzsch method for the rapid and accurate photometrical phytate determination in soybean, wheat, and maize meals.

    PubMed

    Reichwald, Kirsten; Hatzack, Frank

    2008-05-14

    A modified version of the Haug and Lantzsch method for rapid photometrical phytate determination was applied for the analysis of phytate in soybean, wheat, and maize meals. In comparison to the original protocol, the amount of the toxic reagent thioglycolic acid is reduced substantially to minimize potential health risks for laboratory personnel. Different extraction conditions for soybean meal were tested, and boiling for at least 30 min was found to be necessary to remove an interfering compound in soybean meal extracts. Phytate contents determined according to the modified Haug and Lantzsch method did not differ from those obtained by measuring total precipitated phosphorus or by sensitive and specific high-performance ion chromatography. Applicability and accuracy of the modified method for phytate analysis in major feed substrates, including soy-based textured vegetable protein, were demonstrated.

  3. Weeds in fields with contrasting conventional and genetically modified herbicide-tolerant crops. I. Effects on abundance and diversity.

    PubMed Central

    Heard, M S; Hawes, C; Champion, G T; Clark, S J; Firbank, L G; Haughton, A J; Parish, A M; Perry, J N; Rothery, P; Scott, R J; Skellern, M P; Squire, G R; Hill, M O

    2003-01-01

    We compared the seedbanks, seed rains, plant densities and biomasses of weeds under two contrasting systems of management in beet, maize and spring oilseed rape. Weed seedbank and plant density were measured at the same locations in two subsequent seasons. About 60 fields were sown with each crop. Each field was split, one half being sown with a conventional variety managed according to the farmer's normal practice, the other half being sown with a genetically modified herbicide-tolerant (GMHT) variety, with weeds controlled by a broad-spectrum herbicide. In beet and rape, plant densities shortly after sowing were higher in the GMHT treatment. Following weed control in conventional beet, plant densities were approximately one-fifth of those in GMHT beet. In both beet and rape, this effect was reversed after the first application of broad-spectrum herbicide, so that late-season plant densities were lower in the GMHT treatments. Biomass and seed rain in GMHT crops were between one-third and one-sixth of those in conventional treatments. The effects of differing weed-seed returns in these two crops persisted in the seedbank: densities following the GMHT treatment were about 20% lower than those following the conventional treatment. The effect of growing maize was quite different. Weed density was higher throughout the season in the GMHT treatment. Late-season biomass was 82% higher and seed rain was 87% higher than in the conventional treatment. The difference was not subsequently detectable in the seedbank because the total seed return was low after both treatments. In all three crops, weed diversity was little affected by the treatment, except for transient effects immediately following herbicide application. PMID:14561316

  4. Genetic Modifiers of MeCP2 Function in Drosophila

    PubMed Central

    Cukier, Holly N.; Perez, Alma M.; Collins, Ann L.; Zhou, Zhaolan; Zoghbi, Huda Y.; Botas, Juan

    2008-01-01

    The levels of methyl-CpG–binding protein 2 (MeCP2) are critical for normal post-natal development and function of the nervous system. Loss of function of MeCP2, a transcriptional regulator involved in chromatin remodeling, causes classic Rett syndrome (RTT) as well as other related conditions characterized by autism, learning disabilities, or mental retardation. Increased dosage of MeCP2 also leads to clinically similar neurological disorders and mental retardation. To identify molecular mechanisms capable of compensating for altered MeCP2 levels, we generated transgenic Drosophila overexpressing human MeCP2. We find that MeCP2 associates with chromatin and is phosphorylated at serine 423 in Drosophila, as is found in mammals. MeCP2 overexpression leads to anatomical (i.e., disorganized eyes, ectopic wing veins) and behavioral (i.e., motor dysfunction) abnormalities. We used a candidate gene approach to identify genes that are able to compensate for abnormal phenotypes caused by MeCP2 increased activity. These genetic modifiers include other chromatin remodeling genes (Additional sex combs, corto, osa, Sex combs on midleg, and trithorax), the kinase tricornered, the UBE3A target pebble, and Drosophila homologues of the MeCP2 physical interactors Sin3a, REST, and N-CoR. These findings demonstrate that anatomical and behavioral phenotypes caused by MeCP2 activity can be ameliorated by altering other factors that might be more amenable to manipulation than MeCP2 itself. PMID:18773074

  5. Molecular toolbox for the identification of unknown genetically modified organisms.

    PubMed

    Ruttink, Tom; Demeyer, Rolinde; Van Gulck, Elke; Van Droogenbroeck, Bart; Querci, Maddalena; Taverniers, Isabel; De Loose, Marc

    2010-03-01

    Competent laboratories monitor genetically modified organisms (GMOs) and products derived thereof in the food and feed chain in the framework of labeling and traceability legislation. In addition, screening is performed to detect the unauthorized presence of GMOs including asynchronously authorized GMOs or GMOs that are not officially registered for commercialization (unknown GMOs). Currently, unauthorized or unknown events are detected by screening blind samples for commonly used transgenic elements, such as p35S or t-nos. If (1) positive detection of such screening elements shows the presence of transgenic material and (2) all known GMOs are tested by event-specific methods but are not detected, then the presence of an unknown GMO is inferred. However, such evidence is indirect because it is based on negative observations and inconclusive because the procedure does not identify the causative event per se. In addition, detection of unknown events is hampered in products that also contain known authorized events. Here, we outline alternative approaches for analytical detection and GMO identification and develop new methods to complement the existing routine screening procedure. We developed a fluorescent anchor-polymerase chain reaction (PCR) method for the identification of the sequences flanking the p35S and t-nos screening elements. Thus, anchor-PCR fingerprinting allows the detection of unique discriminative signals per event. In addition, we established a collection of in silico calculated fingerprints of known events to support interpretation of experimentally generated anchor-PCR GM fingerprints of blind samples. Here, we first describe the molecular characterization of a novel GMO, which expresses recombinant human intrinsic factor in Arabidopsis thaliana. Next, we purposefully treated the novel GMO as a blind sample to simulate how the new methods lead to the molecular identification of a novel unknown event without prior knowledge of its transgene

  6. Attitudes of agricultural scientists in Indonesia towards genetically modified foods.

    PubMed

    Februhartanty, Judhiastuty; Widyastuti, Tri Nisa; Iswarawanti, Dwi Nastiti

    2007-01-01

    Conflicting arguments and partial truths on genetically modified (GM) foods have left confusion. Although studies of consumer acceptance of GM foods are numerous, the study of scientists is limited. Therefore, the main objective of this study was to assess the attitudes of scientists towards GM foods. The study was a cross sectional study. A total of 400 scientists (involved in at least one of teaching, research and consultancy) in the Bogor Agricultural Institute, Indonesia were selected randomly from its faculties of agriculture, veterinary, fishery, animal husbandry, forestry, agricultural technology, mathematics and science, and the post graduate department. Data collection was done by face-to-face interview using a structured questionnaire and self-administered questionnaire. The result showed that the majority (72.8%) of the respondents were favorably disposed towards GM foods, 14.8% were neutral, and only 12.5% were against them. The majority (78.3%) stated that they would try GM food if offered. Most (71%) reported that they were aware of the term "GM foods". Only half of the respondents felt that they had a basic understanding about GM foods. However, based on a knowledge test, 69.8% had a good knowledge score. Nearly 50% indicated that they were more exposed to news which supported GM foods. Over 90% said that there should be some form of labeling to distinguish food containing GM ingredients from non-GM foods. Attitudes were significantly associated with willingness to try GM foods if offered, restrictions on GM foods, and exposure to media reports about the pros and cons of GM foods.

  7. Factors influencing stakeholders attitudes toward genetically modified aedes mosquito.

    PubMed

    Amin, Latifah; Hashim, Hasrizul

    2015-06-01

    Dengue fever is a debilitating and infectious disease that could be life-threatening. It is caused by the dengue virus which affects millions of people in the tropical area. Currently, there is no cure for the disease as there is no vaccine available. Thus, prevention of the vector population using conventional methods is by far the main strategy but has been found ineffective. A genetically modified (GM) mosquito is among the favoured alternatives to curb dengue fever in Malaysia. Past studies have shown that development and diffusion of gene technology products depends heavily upon public acceptance. The purpose of this study is to identify the relevant factors influencing stakeholders' attitudes toward the GM Aedes mosquito and to analyse the relationships between all the factors using the structural equation model. A survey was carried out on 509 respondents from various stakeholder groups in the Klang Valley region of Malaysia. Results of the survey have confirmed that public perception towards complex issues such as gene technology should be seen as a multi-faceted process. The perceived benefit-perceived risk balance is very important in determining the most predominant predictor of attitudes toward a GM mosquito. In this study the stakeholders perceived the benefit of the GM mosquito as outweighing its risk, translating perceived benefit as the most important direct predictor of attitudes toward the GM mosquito. Trust in key players has a direct influence on attitudes toward the GM mosquito while moral concern exhibited an indirect influence through perceived benefits. Other factors such as attitudes toward technology and nature were also indirect predictors of attitudes toward the GM mosquito while religiosity and engagement did not exhibited any significant roles. The research findings serve as a useful database to understand public acceptance and the social construct of public attitudes towards the GM mosquito to combat dengue.

  8. Transgene × Environment Interactions in Genetically Modified Wheat

    PubMed Central

    Zeller, Simon L.; Kalinina, Olena; Brunner, Susanne; Keller, Beat; Schmid, Bernhard

    2010-01-01

    Background The introduction of transgenes into plants may cause unintended phenotypic effects which could have an impact on the plant itself and the environment. Little is published in the scientific literature about the interrelation of environmental factors and possible unintended effects in genetically modified (GM) plants. Methods and Findings We studied transgenic bread wheat Triticum aestivum lines expressing the wheat Pm3b gene against the fungus powdery mildew Blumeria graminis f.sp. tritici. Four independent offspring pairs, each consisting of a GM line and its corresponding non-GM control line, were grown under different soil nutrient conditions and with and without fungicide treatment in the glasshouse. Furthermore, we performed a field experiment with a similar design to validate our glasshouse results. The transgene increased the resistance to powdery mildew in all environments. However, GM plants reacted sensitive to fungicide spraying in the glasshouse. Without fungicide treatment, in the glasshouse GM lines had increased vegetative biomass and seed number and a twofold yield compared with control lines. In the field these results were reversed. Fertilization generally increased GM/control differences in the glasshouse but not in the field. Two of four GM lines showed up to 56% yield reduction and a 40-fold increase of infection with ergot disease Claviceps purpurea compared with their control lines in the field experiment; one GM line was very similar to its control. Conclusions Our results demonstrate that, depending on the insertion event, a particular transgene can have large effects on the entire phenotype of a plant and that these effects can sometimes be reversed when plants are moved from the glasshouse to the field. However, it remains unclear which mechanisms underlie these effects and how they may affect concepts in molecular plant breeding and plant evolutionary ecology. PMID:20635001

  9. Clinical and laboratory investigation of allergy to genetically modified foods.

    PubMed

    Bernstein, Jonathan A; Bernstein, I Leonard; Bucchini, Luca; Goldman, Lynn R; Hamilton, Robert G; Lehrer, Samuel; Rubin, Carol; Sampson, Hugh A

    2003-06-01

    Technology has improved the food supply since the first cultivation of crops. Genetic engineering facilitates the transfer of genes among organisms. Generally, only minute amounts of a specific protein need to be expressed to obtain the desired trait. Food allergy affects only individuals with an abnormal immunologic response to food--6% of children and 1.5-2% of adults in the United States. Not all diseases caused by food allergy are mediated by IgE. A number of expert committees have advised the U.S. government and international organizations on risk assessment for allergenicity of food proteins. These committees have created decision trees largely based on assessment of IgE-mediated food allergenicity. Difficulties include the limited availability of allergen-specific IgE antisera from allergic persons as validated source material, the utility of specific IgE assays, limited characterization of food proteins, cross-reactivity between food and other allergens, and modifications of food proteins by processing. StarLink was a corn variety modified to produce a (Italic)Bacillus thuringiensis(/Italic) (Bt) endotoxin, Cry9C. The Centers for Disease Control and Prevention investigated 51 reports of possible adverse reactions to corn that occurred after the announcement that StarLink, allowed for animal feed, was found in the human food supply. Allergic reactions were not confirmed, but tools for postmarket assessment were limited. Workers in agricultural and food preparation facilities have potential inhalation exposure to plant dusts and flours. In 1999, researchers found that migrant health workers can become sensitized to certain Bt spore extracts after exposure to Bt spraying.

  10. Clinical and laboratory investigation of allergy to genetically modified foods.

    PubMed Central

    Bernstein, Jonathan A; Bernstein, I Leonard; Bucchini, Luca; Goldman, Lynn R; Hamilton, Robert G; Lehrer, Samuel; Rubin, Carol; Sampson, Hugh A

    2003-01-01

    Technology has improved the food supply since the first cultivation of crops. Genetic engineering facilitates the transfer of genes among organisms. Generally, only minute amounts of a specific protein need to be expressed to obtain the desired trait. Food allergy affects only individuals with an abnormal immunologic response to food--6% of children and 1.5-2% of adults in the United States. Not all diseases caused by food allergy are mediated by IgE. A number of expert committees have advised the U.S. government and international organizations on risk assessment for allergenicity of food proteins. These committees have created decision trees largely based on assessment of IgE-mediated food allergenicity. Difficulties include the limited availability of allergen-specific IgE antisera from allergic persons as validated source material, the utility of specific IgE assays, limited characterization of food proteins, cross-reactivity between food and other allergens, and modifications of food proteins by processing. StarLink was a corn variety modified to produce a (Italic)Bacillus thuringiensis(/Italic) (Bt) endotoxin, Cry9C. The Centers for Disease Control and Prevention investigated 51 reports of possible adverse reactions to corn that occurred after the announcement that StarLink, allowed for animal feed, was found in the human food supply. Allergic reactions were not confirmed, but tools for postmarket assessment were limited. Workers in agricultural and food preparation facilities have potential inhalation exposure to plant dusts and flours. In 1999, researchers found that migrant health workers can become sensitized to certain Bt spore extracts after exposure to Bt spraying. PMID:12826483

  11. Genetic and molecular characterization of the maize rp3 rust resistance locus.

    PubMed Central

    Webb, Craig A; Richter, Todd E; Collins, Nicholas C; Nicolas, Marie; Trick, Harold N; Pryor, Tony; Hulbert, Scot H

    2002-01-01

    In maize, the Rp3 gene confers resistance to common rust caused by Puccinia sorghi. Flanking marker analysis of rust-susceptible rp3 variants suggested that most of them arose via unequal crossing over, indicating that rp3 is a complex locus like rp1. The PIC13 probe identifies a nucleotide binding site-leucine-rich repeat (NBS-LRR) gene family that maps to the complex. Rp3 variants show losses of PIC13 family members relative to the resistant parents when probed with PIC13, indicating that the Rp3 gene is a member of this family. Gel blots and sequence analysis suggest that at least 9 family members are at the locus in most Rp3-carrying lines and that at least 5 of these are transcribed in the Rp3-A haplotype. The coding regions of 14 family members, isolated from three different Rp3-carrying haplotypes, had DNA sequence identities from 93 to 99%. Partial sequencing of clones of a BAC contig spanning the rp3 locus in the maize inbred line B73 identified five different PIC13 paralogues in a region of approximately 140 kb. PMID:12242248

  12. Maize susceptibility to Ustilago maydis is influenced by genetic and chemical perturbation of carbohydrate allocation.

    PubMed

    Kretschmer, Matthias; Croll, Daniel; Kronstad, James W

    2016-08-26

    The ability of biotrophic fungi to metabolically adapt to the host environment is a critical factor in fungal diseases of crop plants. In this study, we analysed the transcriptome of maize tumours induced by Ustilago maydis to identify key features underlying metabolic shifts during disease. Among other metabolic changes, this analysis highlighted modifications during infection in the transcriptional regulation of carbohydrate allocation and starch metabolism. We confirmed the relevance of these changes by establishing that symptom development was altered in an id1 (indeterminate1) mutant that showed increased accumulation of sucrose as well as being defective in the vegetative to reproductive transition. We further established the relevance of specific metabolic functions related to carbohydrate allocation by assaying disease in su1 (sugary1) mutant plants with altered starch metabolism and in plants treated with glucose, sucrose and silver nitrate during infection. We propose that specific regulatory and metabolic changes influence the balance between susceptibility and resistance by altering carbon allocation to promote fungal growth or to influence plant defence. Taken together, these studies reveal key aspects of metabolism that are critical for biotrophic adaptation during the maize-U. maydis interaction.

  13. A BAC pooling strategy combined with PCR-based screenings in a large, highly repetitive genome enables integration of the maize genetic and physical maps

    PubMed Central

    Yim, Young-Sun; Moak, Patricia; Sanchez-Villeda, Hector; Musket, Theresa A; Close, Pamela; Klein, Patricia E; Mullet, John E; McMullen, Michael D; Fang, Zheiwei; Schaeffer, Mary L; Gardiner, Jack M; Coe, Edward H; Davis, Georgia L

    2007-01-01

    Background Molecular markers serve three important functions in physical map assembly. First, they provide anchor points to genetic maps facilitating functional genomic studies. Second, they reduce the overlap required for BAC contig assembly from 80 to 50 percent. Finally, they validate assemblies based solely on BAC fingerprints. We employed a six-dimensional BAC pooling strategy in combination with a high-throughput PCR-based screening method to anchor the maize genetic and physical maps. Results A total of 110,592 maize BAC clones (~ 6x haploid genome equivalents) were pooled into six different matrices, each containing 48 pools of BAC DNA. The quality of the BAC DNA pools and their utility for identifying BACs containing target genomic sequences was tested using 254 PCR-based STS markers. Five types of PCR-based STS markers were screened to assess potential uses for the BAC pools. An average of 4.68 BAC clones were identified per marker analyzed. These results were integrated with BAC fingerprint data generated by the Arizona Genomics Institute (AGI) and the Arizona Genomics Computational Laboratory (AGCoL) to assemble the BAC contigs using the FingerPrinted Contigs (FPC) software and contribute to the construction and anchoring of the physical map. A total of 234 markers (92.5%) anchored BAC contigs to their genetic map positions. The results can be viewed on the integrated map of maize [1,2]. Conclusion This BAC pooling strategy is a rapid, cost effective method for genome assembly and anchoring. The requirement for six replicate positive amplifications makes this a robust method for use in large genomes with high amounts of repetitive DNA such as maize. This strategy can be used to physically map duplicate loci, provide order information for loci in a small genetic interval or with no genetic recombination, and loci with conflicting hybridization-based information. PMID:17291341

  14. Stable Carbon Isotope Discrimination Is under Genetic Control in the C4 Species Maize with Several Genomic Regions Influencing Trait Expression1[W

    PubMed Central

    Gresset, Sebastian; Westermeier, Peter; Rademacher, Svenja; Ouzunova, Milena; Presterl, Thomas; Westhoff, Peter; Schön, Chris-Carolin

    2014-01-01

    In plants with C4 photosynthesis, physiological mechanisms underlying variation in stable carbon isotope discrimination (Δ13C) are largely unknown, and genetic components influencing Δ13C have not been described. We analyzed a maize (Zea mays) introgression library derived from two elite parents to investigate whether Δ13C is under genetic control in this C4 species. High-density genotyping with the Illumina MaizeSNP50 Bead Chip was used for a detailed structural characterization of 89 introgression lines. Phenotypic analyses were conducted in the field and in the greenhouse for kernel Δ13C as well as plant developmental and photosynthesis-related traits. Highly heritable significant genetic variation for Δ13C was detected under field and greenhouse conditions. For several introgression library lines, Δ13C values consistently differed from the recurrent parent within and across the two phenotyping platforms. Δ13C was significantly associated with 22 out of 164 analyzed genomic regions, indicating a complex genetic architecture of Δ13C. The five genomic regions with the largest effects were located on chromosomes 1, 2, 6, 7, and 9 and explained 55% of the phenotypic variation for Δ13C. Plant development stage had no effect on Δ13C expression, as phenotypic as well as genotypic correlations between Δ13C, flowering time, and plant height were not significant. To our knowledge, this is the first study demonstrating Δ13C to be under polygenic control in the C4 species maize. PMID:24280436

  15. Choosing a Genome Browser for a Model Organism Database (MOD): Surveying the Maize Community

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As the maize genome sequencing is nearing its completion, the Maize Genetics and Genomics Database (MaizeGDB), the Model Organism Database for maize, integrated a genome browser to its already existing Web interface and database. The addition of the MaizeGDB Genome Browser to MaizeGDB will allow it ...

  16. Genetic relationships among Italian and Mexican maize-rhizosphere Burkholderia cepacia complex (BCC) populations belonging to Burkholderia cenocepacia IIIB and BCC6 group

    PubMed Central

    2011-01-01

    Background A close association between maize roots and Burkholderia cepacia complex (BCC) bacteria has been observed in different locations globally. In this study we investigated by MultiLocus Restriction Typing (MLRT) the genetic diversity and relationships among Burkholderia cenocepacia IIIB and BCC6 populations associated with roots of maize plants cultivated in geographically distant countries (Italy and Mexico), in order to provide new insights into their population structure, evolution and ecology. Results The 31 B. cenocepacia IIIB and 65 BCC6 isolates gave rise to 29 and 39 different restriction types (RTs), respectively. Two pairs of isolates of B. cenocepacia IIIB and BCC6, recovered from both Italian and Mexican maize rhizospheres, were found to share the same RT. The eBURST (Based Upon Related Sequence Types) analysis of MLRT data grouped all the B. cenocepacia IIIB isolates into four clonal complexes, with the RT-4-complex including the 42% of them, while the majority of the BCC6 isolates (94%) were grouped into the RT-104-complex. These two main clonal complexes included RTs shared by both Italian and Mexican maize rhizospheres and a clear relationship between grouping and maize variety was also found. Grouping established by eBURST correlated well with the assessment using unweighted-pair group method with arithmetic mean (UPGMA). The standardized index of association values obtained in both B. cenocepacia IIIB and BCC6 suggests an epidemic population structure in which occasional clones emerge and spread. Conclusions Taken together our data demonstrate a wide dispersal of certain B. cenocepacia IIIB and BCC6 isolates in Mexican and Italian maize rhizospheres. Despite the clear relationship found between the geographic origin of isolates and grouping, identical RTs and closely related isolates were observed in geographically distant regions. Ecological factors and selective pressure may preferably promote some genotypes within each local microbial

  17. Consumer reaction to information on the labels of genetically modified food

    PubMed Central

    Sebastian-Ponce, Miren Itxaso; Sanz-Valero, Javier; Wanden-Berghe, Carmina

    2014-01-01

    OBJECTIVE To analyze consumer opinion on genetically modified foods and the information included on the label. METHODS A systematic review of the scientific literature on genetically modified food labeling was conducted consulting bibliographic databases (Medline – via PubMed –, EMBASE, ISI-Web of knowledge, Cochrane Library Plus, FSTA, LILACS, CINAHL and AGRICOLA) using the descriptors “organisms, genetically modified” and “food labeling”. The search covered the first available date, up to June 2012, selecting relevant articles written in English, Portuguese or Spanish. RESULTS Forty articles were selected after applying the inclusion and exclusion criteria. All of them should have conducted a population-based intervention focused on consumer awareness of genetically modified foods and their need or not, to include this on the label. The consumers expressed a preference for non-genetically modified products, and added that they were prepared to pay more for this but, ultimately, the product bought was that with the best price, in a market which welcomes new technologies. In 18 of the articles, the population was in favor of obligatory labelling, and in six, in favor of this being voluntary; seven studies showed the consumer knew little about genetically modified food, and in three, the population underestimated the quantity they consumed. Price was an influencing factor in all cases. CONCLUSIONS Label should be homogeneous and clarify the degree of tolerance of genetically modified products in humans, in comparison with those non-genetically modified. Label should also present the content or not of genetically modified products and how these commodities are produced and should be accompanied by the certifying entity and contact information. Consumers express their preference for non-genetically modifiedproducts and they even notice that they are willing to pay more for it, but eventually they buy the item with the best price, in a market that welcomes

  18. Recent advances in genome editing and creation of genetically modified pigs.

    PubMed

    Butler, James R; Ladowski, Joseph M; Martens, Gregory R; Tector, Matthew; Tector, A Joseph

    2015-11-01

    The field of xenotransplantation is benefiting greatly from recent advances in genetic engineering. The efficiency and pace with which new model animals are being created has dramatically sped progress towards clinical relevance. Endonuclease-driven genome editing now allows for the efficient generation of targeted genetic alterations. Herein we review the available methods of genetic engineering that have been successfully employed to create genetically modified pigs.

  19. Preventing the spread of malaria and dengue fever using genetically modified mosquitoes.

    PubMed

    James, Anthony A

    2007-01-01

    In this candid interview, Anthony A. James explains how mosquito genetics can be exploited to control malaria and dengue transmission. Population replacement strategy, the idea that transgenic mosquitoes can be released into the wild to control disease transmission, is introduced, as well as the concept of genetic drive and the design criterion for an effective genetic drive system. The ethical considerations of releasing genetically-modified organisms into the wild are also discussed.

  20. Classical genetic and quantitative trait loci analyses of heterosis in a maize hybrid between two elite inbred lines.

    PubMed

    Frascaroli, Elisabetta; Canè, Maria Angela; Landi, Pierangelo; Pea, Giorgio; Gianfranceschi, Luca; Villa, Marzio; Morgante, Michele; Pè, Mario Enrico

    2007-05-01

    The exploitation of heterosis is one of the most outstanding advancements in plant breeding, although its genetic basis is not well understood yet. This research was conducted on the materials arising from the maize single cross B73 x H99 to study heterosis by procedures of classical genetic and quantitative trait loci (QTL) analyses. Materials were the basic generations, the derived 142 recombinant inbred lines (RILs), and the three testcross populations obtained by crossing the 142 RILs to each parent and their F(1). For seedling weight (SW), number of kernels per plant (NK), and grain yield (GY), heterosis was >100% and the average degree of dominance was >1. Epistasis was significant for SW and NK but not for GY. Several QTL were identified and in most cases they were in the additive-dominance range for traits with low heterosis and mostly in the dominance-overdominance range for plant height (PH), SW, NK, and GY. Only a few QTL with digenic epistasis were identified. The importance of dominance effects was confirmed by highly significant correlations between heterozygosity level and phenotypic performance, especially for GY. Some chromosome regions presented overlaps of overdominant QTL for SW, PH, NK, and GY, suggesting pleiotropic effects on overall plant vigor.

  1. Avoiding genetically modified foods in GMO Ground Zero: A reflective self-narrative.

    PubMed

    Edwards, Sachi

    2015-05-01

    I engage in a reflective self-narrative of my experience attempting to maintain a diet free of genetically modified organisms. Social tension over the genetically modified organism industry in Hawai'i, United States, has led to public debates over jobs and social identities. Drawing on local media sources, grassroots organizations, and blog posts, I describe the way this tension has shaped my experience with food, eating, and being with others as a genetically modified organism avoider. I utilize discursive positioning to make sense of my experiences by locating them within the ongoing public conversations that give structure to the daily lives of Hawai'i's residents.

  2. Recombination in maize is stable, predictable, and associated with genetic load: a joint study of the US and Chinese maize NAM populations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Among the fundamental evolutionary forces, recombination arguably has the largest impact on the practical work of plant breeders. Varying over 1,000-fold across the maize genome, the local meiotic recombination rate limits the resolving power of quantitative trait mapping and the precision of favora...

  3. Romanian Maize (Zea mays) Inbred Lines as a Source of Genetic Diversity in SE Europe, and Their Potential in Future Breeding Efforts

    PubMed Central

    Haș, Voichița; Haș, Ioan; Miclăuș, Mihai

    2013-01-01

    Maize has always been under constant human selection ever since it had been domesticated. Intensive breeding programs that resulted in the massive use of hybrids nowadays have started in the 60s. That brought significant yield increases but reduced the genetic diversity at the same time. Consequently, breeders and researchers alike turned their attention to national germplasm collections established decades ago in many countries, as they may hold allelic variations that could prove useful for future improvements. These collections are mainly composed of inbred lines originating from well-adapted local open pollinated varieties. However, there is an overall lack of data in the literature about the genetic diversity of maize in SE Europe, and its potential for future breeding efforts. There are no data, whatsoever, on the nutritional quality of the grain, primarily dictated by the zein proteins. We therefore sought to use the Romanian maize germplasm as an entry point in understanding the molecular make-up of maize in this part of Europe. By using 80 SSR markers, evenly spread throughout the genome, on 82 inbred lines from various parts of the country, we were able to decipher population structure and the existing relationships between those and the eight international standards used, including the reference sequenced genome B73. Corroborating molecular data with a standardized morphological, physiological, and biochemical characterization of all 90 inbred lines, this is the first comprehensive such study on the existing SE European maize germplasm. The inbred lines we present here are an important addition to the ever-shrinking gene pool that the breeding programs are faced-with, because of the allelic richness they hold. They may serve as parental lines in crosses that will lead to new hybrids, characterized by a high level of heterosis, nationwide and beyond, due to their existing relationship with the international germplasm. PMID:24392016

  4. Romanian maize (Zea mays) inbred lines as a source of genetic diversity in SE Europe, and their potential in future breeding efforts.

    PubMed

    Şuteu, Dana; Băcilă, Ioan; Haș, Voichița; Haș, Ioan; Miclăuș, Mihai

    2013-01-01

    Maize has always been under constant human selection ever since it had been domesticated. Intensive breeding programs that resulted in the massive use of hybrids nowadays have started in the 60s. That brought significant yield increases but reduced the genetic diversity at the same time. Consequently, breeders and researchers alike turned their attention to national germplasm collections established decades ago in many countries, as they may hold allelic variations that could prove useful for future improvements. These collections are mainly composed of inbred lines originating from well-adapted local open pollinated varieties. However, there is an overall lack of data in the literature about the genetic diversity of maize in SE Europe, and its potential for future breeding efforts. There are no data, whatsoever, on the nutritional quality of the grain, primarily dictated by the zein proteins. We therefore sought to use the Romanian maize germplasm as an entry point in understanding the molecular make-up of maize in this part of Europe. By using 80 SSR markers, evenly spread throughout the genome, on 82 inbred lines from various parts of the country, we were able to decipher population structure and the existing relationships between those and the eight international standards used, including the reference sequenced genome B73. Corroborating molecular data with a standardized morphological, physiological, and biochemical characterization of all 90 inbred lines, this is the first comprehensive such study on the existing SE European maize germplasm. The inbred lines we present here are an important addition to the ever-shrinking gene pool that the breeding programs are faced-with, because of the allelic richness they hold. They may serve as parental lines in crosses that will lead to new hybrids, characterized by a high level of heterosis, nationwide and beyond, due to their existing relationship with the international germplasm.

  5. The Genetic Modifiers of Motor Onset Age (GeM MOA) website: genome-wide association analysis for genetic modifiers of Huntington's disease

    PubMed Central

    Correia, Kevin; Harold, Denise; Kim, Kyung-Hee; Holmans, Peter; Jones, Lesley; Orth, Michael; Myers, Richard H.; Kwak, Seung; Wheeler, Vanessa C.; MacDonald, Marcy E.; Gusella, James F.; Lee, Jong-Min

    2016-01-01

    BACKGROUND Huntington's disease (HD) is a dominantly inherited disease caused by a CAG expansion mutation in HTT. The age at onset of clinical symptoms is determined primarily by the length of this CAG expansion but is also influenced by other genetic and/or environmental factors. OBJECTIVE Recently, through genome-wide association studies (GWAS) aimed at discovering genetic modifiers, we identified loci associated with age at onset of motor signs that are significant at the genome-wide level. However, many additional HD modifiers may exist but may not have achieved statistical significance due to limited power. METHODS In order to disseminate broadly the entire GWAS results and make them available to complement alternative approaches, we have developed the internet website "GeM MOA" where genetic association results can be searched by gene name, SNP ID, or genomic coordinates of a region of interest. RESULTS Users of the Genetic Modifiers of Motor Onset Age (GeM MOA) site can therefore examine support for association between any gene region and age at onset of HD motor signs. GeM MOA's interactive interface also allows users to navigate the surrounding region and to obtain association p-values for individual SNPs. CONCLUSIONS Our website conveys a comprehensive view of the genetic landscape of modifiers of HD from the existing GWAS, and will provide the means to evaluate the potential influence of genes of interest on the onset of HD. GeM MOA is freely available at https://www.hdinhd.org/. PMID:26444025

  6. Exploiting the Genetic Diversity of Maize using a Combined Metabolomic, Enzyme Activity Profiling, and Metabolic Modelling Approach to Link Leaf Physiology to Kernel Yield.

    PubMed

    Cañas, Rafael A; Yesbergenova-Cuny, Zhazira; Simons, Margaret; Chardon, Fabien; Armengaud, Patrick; Quilleré, Isabelle; Cukier, Caroline; Gibon, Yves; Limami, Anis M; Nicolas, Stéphane D; Brulé, Lénaïg; Lea, Peter J; Maranas, Costas D; Hirel, Bertrand

    2017-04-10

    A combined metabolomic, biochemical, fluxomic, and metabolic modelling approach was developed using nineteen genetically distant maize (Zea mays L.) lines from Europe and America. Considerable differences were detected between the lines when leaf metabolic profiles and activities of the main enzymes involved in primary metabolism were compared. During grain filling, the leaf metabolic composition appeared to be a reliable marker, allowing a classification matching the genetic diversity of the lines. During the same period, there was a significant correlation between the genetic distance of the lines and the activities of enzymes involved in carbon metabolism, notably glycolysis. Although large differences were observed in terms of leaf metabolic fluxes, these variations were not tightly linked to the genome structure of the lines. Both correlation studies and metabolic network analyses allowed the description of a maize ideotype with a high grain yield potential. Such an ideotype is characterized by low accumulation of soluble amino acids and carbohydrates in the leaves and high activity of enzymes involved in the C4 photosynthetic pathway and in the biosynthesis of amino acids derived from glutamate. Chlorogenates appear to be important markers that can be used to select for maize lines that produce larger kernels.

  7. Multiple organ histopathological changes in broiler chickens fed on genetically modified organism.

    PubMed

    Cîrnatu, Daniela; Jompan, A; Sin, Anca Ileana; Zugravu, Cornelia Aurelia

    2011-01-01

    Diet can influence the structural characteristics of internal organs. An experiment involving 130 meat broilers was conducted during 42 days (life term for a meat broiler) to study the effect of feed with protein from genetically modified soy. The 1-day-old birds were randomly allocated to five study groups, fed with soy, sunflower, wheat, fish flour, PC starter. In the diet of each group, an amount of protein from soy was replaced with genetically modified soy (I - 0%, II - 25%, III - 50%, IV - 75%, V - 100% protein from genetically modified soy). The level of protein in soy, either modified, or non-modified, was the same. Organs and carcass weights were measured at about 42 days of age of the birds and histopathology exams were performed during May-June 2009. No statistically significant differences were observed in mortality, growth performance variables or carcass and organ yields between broilers consuming diets produced with genetically modified soybean fractions and those consuming diets produced with near-isoline control soybean fractions. Inflammatory and degenerative liver lesions, muscle hypertrophy, hemorrhagic necrosis of bursa, kidney focal tubular necrosis, necrosis and superficial ulceration of bowel and pancreatic dystrophies were found in tissues from broilers fed on protein from genetically modified soy. Different types of lesions found in our study might be due to other causes (parasites, viral) superimposed but their presence exclusively in groups fed with modified soy raises some serious questions about the consequences of use of this type of feed.

  8. Degradation of Cry1Ab protein from genetically modified maize in the bovine gastrointestinal tract.

    PubMed

    Lutz, Bodo; Wiedemann, Steffi; Einspanier, Ralf; Mayer, Johann; Albrecht, Christiane

    2005-03-09

    Immunoblotting assays using commercial antibodies were established to investigate the unexpected persistence of the immunoactive Cry1Ab protein in the bovine gastrointestinal tract (GIT) previously suggested by enzyme-linked immunosorbent assay (ELISA). Samples of two different feeding experiments in cattle were analyzed with both ELISA and immunoblotting methods. Whereas results obtained by ELISA suggested that the concentration of the Cry1Ab protein increased during the GIT passage, the immunoblotting assays revealed a significant degradation of the protein in the bovine GIT. Samples showing a positive signal in the ELISA consisted of fragmented Cry1Ab protein of approximately 17 and 34 kDa size. Two independent sets of gastrointestinal samples revealed the apparent discrepancy between the results obtained by ELISA and immunoblotting, suggesting that the antibody used in the ELISA reacts with fragmented yet immunoactive epitopes of the Cry1Ab protein. It was concluded that Cry1Ab protein is degraded during digestion in cattle. To avoid misinterpretation, samples tested positive for Cry1Ab protein by ELISA should be reassessed by another technique.

  9. Definition and feasibility of isolation distances for transgenic maize cultivation.

    PubMed

    Sanvido, Olivier; Widmer, Franco; Winzeler, Michael; Streit, Bernhard; Szerencsits, Erich; Bigler, Franz

    2008-06-01

    A major concern related to the adoption of genetically modified (GM) crops in agricultural systems is the possibility of unwanted GM inputs into non-GM crop production systems. Given the increasing commercial cultivation of GM crops in the European Union (EU), there is an urgent need to define measures to prevent mixing of GM with non-GM products during crop production. Cross-fertilization is one of the various mechanisms that could lead to GM-inputs into non-GM crop systems. Isolation distances between GM and non-GM fields are widely accepted to be an effective measure to reduce these inputs. However, the question of adequate isolation distances between GM and non-GM maize is still subject of controversy both amongst scientists and regulators. As several European countries have proposed largely differing isolation distances for maize ranging from 25 to 800 m, there is a need for scientific criteria when using cross-fertilization data of maize to define isolation distances between GM and non-GM maize. We have reviewed existing cross-fertilization studies in maize, established relevant criteria for the evaluation of these studies and applied these criteria to define science-based isolation distances. To keep GM-inputs in the final product well below the 0.9% threshold defined by the EU, isolation distances of 20 m for silage and 50 m for grain maize, respectively, are proposed. An evaluation using statistical data on maize acreage and an aerial photographs assessment of a typical agricultural landscape by means of Geographic Information Systems (GIS) showed that spatial resources would allow applying the defined isolation distances for the cultivation of GM maize in the majority of the cases under actual Swiss agricultural conditions. The here developed approach, using defined criteria to consider the agricultural context of maize cultivation, may be of assistance for the analysis of cross-fertilization data in other countries.

  10. The iojap gene in maize

    SciTech Connect

    Martienssen, Robert

    2001-12-01

    The classical maize mutant iojap (Iodent japonica) has variegated green and white leaves. Green sectors have cells with normal chloroplasts whereas white sectors have cells where plastids fail to differentiate. These mutant plastids, when transmitted through the female gametophyte, do not recover in the presence of wild type Iojap. We cloned the Ij locus, and we have investigated the mechanism of epigenetic inheritance and phenotypic expression. More recently, a modifier of this type of variegation, ''Inhibitor of striate'', has also been cloned. Both the iojap and inhibitor of striate proteins have homologs in bacteria and are members of ancient conserved families found in multiple species. These tools can be used to address fundamental questions of inheritance and variegation associated with this classical conundrum of maize genetics. Since the work of Rhoades there has been considerable speculation concerning the nature of the Iojap gene product, the origin of leaf variegation and the mechanism behind the material inheritance of defective plastids. This has made Iojap a textbook paradigm for cytoplasmic inheritance and nuclear-organellar interaction for almost 50 years. Cloning of the Iojap gene in maize, and homologs in other plants and bacteria, provides a new means to address the origin of heteroplastidity, variegation and cytoplasmic inheritance in higher plants.

  11. [New technology in maize breeding].

    PubMed

    Konstantinov, K; Mladenović, S; Stojkov, S; Delić, N; Gosić, S; Petrović, R; Lević, J; Denić, M

    1992-01-01

    Results obtained by several approaches in the application of Biotechnology in maize breeding are reviewed. RFLP technology in the determination of genetic variation; gene transfer by the use of different methods of gene delivery and the determination of gene integration. Three technologies for foreign gene introduction have been applied; injection of plasmid pRT100 neo into archesporial tissue before micro and macro sporogenesis, slightly modified pollen-tube pathway technology and dry seed incubation in plasmid DNA solution. NPTII gene integration was followed by dot-blot and Southern blot analysis of plant DNA of both T1 and T2 plants. Gene expression was analysed by neomycin phosphotransferase activity. Transformed plants contained the selective NPTII gene sequence in an active form. Bacterial gene integration induced several heritable changes of plant phenotype. As an important change, alteration of the flowering time has been used as a criterion for selection and plant propagation to keep transformed progeny. Besides plant genome transformation, endogenous bacteria living in different maize tissue were found. As a perspective approach for biotechnology application in maize breeding biological vaccine construction has been selected. Therefore, antagonistic effect of gram positive bacterial strains to several pathogenic fungi was investigated. Results obtained after in vivo experiments are discussed.

  12. How scary! An analysis of visual communication concerning genetically modified organisms in Italy.

    PubMed

    Ventura, Vera; Frisio, Dario G; Ferrazzi, Giovanni; Siletti, Elena

    2016-04-01

    Several studies provide evidence of the role of written communication in influencing public perception towards genetically modified organisms, whereas visual communication has been sparsely investigated. This article aims to evaluate the exposure of the Italian population to scary genetically modified organism-related images. A set of 517 images collected through Google are classified considering fearful attributes, and an index that accounts for the scary impact of these images is built. Then, through an ordinary least-squares regression, we estimate the relationship between the Scary Impact Index and a set of variables that describes the context in which the images appear. The results reveal that the first (and most viewed) Google result images contain the most frightful contents. In addition, the agri-food sector in Italy is strongly oriented towards offering a negative representation of genetically modified organisms. Exposure to scary images could be a factor that affects the negative perception of genetically modified organisms in Italy.

  13. USE OF MODELING APPROACHES TO UNDERSTAND POTENTIAL IMPACTS OF GENETICALLY MODIFIED PLANTS ON PLANT COMMUNITIES

    EPA Science Inventory

    Model development is of interest to ecologists, regulators and developers, since it may assist theoretical understanding, decision making in experimental design, product development and risk assessment. In order to predict the potential impacts of genetically modified (GM) plants...

  14. [Progress on biosafety assessment of marker genes in genetically modified foods].

    PubMed

    Yang, Lichen; Yang, Xiaoguang

    2003-05-01

    Marker genes are useful in facilitating the detection of genetically modified organisms(GMO). These genes play an important role during the early identification stage of GMO development, but they exist in the mature genetically modified crops. So the safety assessment of these genes could not be neglected. In this paper, all the study on the biosafety assessment of marker genes were reviewed, their possible hazards and risks were appraised, and the marker genes proved safe were list too. GMO Labeling the is one important regulations for the development of genetically modified foods in the market. The accurate detecting techniques for GMO are the basis for setting up labeling regulation. In addition, some methods used to remove marker genes in genetically modified foods were introduced in the paper, which can eliminate their biosafety concern thoroughly.

  15. Maize (Zea mays L.).

    PubMed

    Frame, Bronwyn; Warnberg, Katey; Main, Marcy; Wang, Kan

    2015-01-01

    Agrobacterium tumefaciens-mediated transformation is an effective method for introducing genes into maize. In this chapter, we describe a detailed protocol for genetic transformation of the maize genotype Hi II. Our starting plant material is immature embryos cocultivated with an Agrobacterium strain carrying a standard binary vector. In addition to step-by-step laboratory transformation procedures, we include extensive details in growing donor plants and caring for transgenic plants in the greenhouse.

  16. [Genetically modified plants and food safety. State of the art and discussion in the European Union].

    PubMed

    Schauzu, M

    2004-09-01

    Placing genetically modified (GM) plants and derived products on the European Union's (EU) market has been regulated by a Community Directive since 1990. This directive was complemented by a regulation specific for genetically modified and other novel foods in 1997. Specific labelling requirements have been applicable for GM foods since 1998. The law requires a pre-market safety assessment for which criteria have been elaborated and continuously adapted in accordance with the state of the art by national and international bodies and organisations. Consequently, only genetically modified products that have been demonstrated to be as safe as their conventional counterparts can be commercialized. However, the poor acceptance of genetically modified foods has led to a de facto moratorium since 1998. It is based on the lack of a qualified majority of EU member states necessary for authorization to place genetically modified plants and derived foods on the market. New Community Regulations are intended to end this moratorium by providing a harmonized and transparent safety assessment, a centralised authorization procedure, extended labelling provisions and a traceability system for genetically modified organisms (GMO) and derived food and feed.

  17. Mutation Scanning in a Single and a Stacked Genetically Modified (GM) Event by Real-Time PCR and High Resolution Melting (HRM) Analysis

    PubMed Central

    Ben Ali, Sina-Elisabeth; Madi, Zita Erika; Hochegger, Rupert; Quist, David; Prewein, Bernhard; Haslberger, Alexander G.; Brandes, Christian

    2014-01-01

    Genetic mutations must be avoided during the production and use of seeds. In the European Union (EU), Directive 2001/18/EC requires any DNA construct introduced via transformation to be stable. Establishing genetic stability is critical for the approval of genetically modified organisms (GMOs). In this study, genetic stability of two GMOs was examined using high resolution melting (HRM) analysis and real-time polymerase chain reaction (PCR) employing Scorpion primers for amplification. The genetic variability of the transgenic insert and that of the flanking regions in a single oilseed rape variety (GT73) and a stacked maize (MON88017 × MON810) was studied. The GT73 and the 5' region of MON810 showed no instabilities in the examined regions. However; two out of 100 analyzed samples carried a heterozygous point mutation in the 3' region of MON810 in the stacked variety. These results were verified by direct sequencing of the amplified PCR products as well as by sequencing of cloned PCR fragments. The occurrence of the mutation suggests that the 5' region is more suitable than the 3' region for the quantification of MON810. The identification of the single nucleotide polymorphism (SNP) in a stacked event is in contrast to the results of earlier studies of the same MON810 region in a single event where no DNA polymorphism was found. PMID:25365178

  18. Environmental distribution and genetic diversity of vegetative compatibility groups determine biocontrol strategies to mitigate aflatoxin contamination of maize by Aspergillus flavus.

    PubMed

    Atehnkeng, Joseph; Donner, Matthias; Ojiambo, Peter S; Ikotun, Babatunde; Augusto, Joao; Cotty, Peter J; Bandyopadhyay, Ranajit

    2016-01-01

    Maize infected by aflatoxin-producing Aspergillus flavus may become contaminated with aflatoxins, and as a result, threaten human health, food security and farmers' income in developing countries where maize is a staple. Environmental distribution and genetic diversity of A. flavus can influence the effectiveness of atoxigenic isolates in mitigating aflatoxin contamination. However, such information has not been used to facilitate selection and deployment of atoxigenic isolates. A total of 35 isolates of A. flavus isolated from maize samples collected from three agro-ecological zones of Nigeria were used in this study. Ecophysiological characteristics, distribution and genetic diversity of the isolates were determined to identify vegetative compatibility groups (VCGs). The generated data were used to inform selection and deployment of native atoxigenic isolates to mitigate aflatoxin contamination in maize. In co-inoculation with toxigenic isolates, atoxigenic isolates reduced aflatoxin contamination in grain by > 96%. A total of 25 VCGs were inferred from the collected isolates based on complementation tests involving nitrate non-utilizing (nit(-)) mutants. To determine genetic diversity and distribution of VCGs across agro-ecological zones, 832 nit(-) mutants from 52 locations in 11 administrative districts were paired with one self-complementary nitrate auxotroph tester-pair for each VCG. Atoxigenic VCGs accounted for 81.1% of the 153 positive complementations recorded. Genetic diversity of VCGs was highest in the derived savannah agro-ecological zone (H = 2.61) compared with the southern Guinea savannah (H = 1.90) and northern Guinea savannah (H = 0.94) zones. Genetic richness (H = 2.60) and evenness (E5  = 0.96) of VCGs were high across all agro-ecological zones. Ten VCGs (40%) had members restricted to the original location of isolation, whereas 15 VCGs (60%) had members located between the original source of isolation and a distance

  19. A Large Maize (Zea mays L.) SNP Genotyping Array: Development and Germplasm Genotyping, and Genetic Mapping to Compare with the B73 Reference Genome

    PubMed Central

    Ganal, Martin W.; Durstewitz, Gregor; Polley, Andreas; Bérard, Aurélie; Buckler, Edward S.; Charcosset, Alain; Clarke, Joseph D.; Graner, Eva-Maria; Hansen, Mark; Joets, Johann; Le Paslier, Marie-Christine; McMullen, Michael D.; Montalent, Pierre; Rose, Mark; Schön, Chris-Carolin; Sun, Qi; Walter, Hildrun; Martin, Olivier C.; Falque, Matthieu

    2011-01-01

    SNP genotyping arrays have been useful for many applications that require a large number of molecular markers such as high-density genetic mapping, genome-wide association studies (GWAS), and genomic selection. We report the establishment of a large maize SNP array and its use for diversity analysis and high density linkage mapping. The markers, taken from more than 800,000 SNPs, were selected to be preferentially located in genes and evenly distributed across the genome. The array was tested with a set of maize germplasm including North American and European inbred lines, parent/F1 combinations, and distantly related teosinte material. A total of 49,585 markers, including 33,417 within 17,520 different genes and 16,168 outside genes, were of good quality for genotyping, with an average failure rate of 4% and rates up to 8% in specific germplasm. To demonstrate this array's use in genetic mapping and for the independent validation of the B73 sequence assembly, two intermated maize recombinant inbred line populations – IBM (B73×Mo17) and LHRF (F2×F252) – were genotyped to establish two high density linkage maps with 20,913 and 14,524 markers respectively. 172 mapped markers were absent in the current B73 assembly and their placement can be used for future improvements of the B73 reference sequence. Colinearity of the genetic and physical maps was mostly conserved with some exceptions that suggest errors in the B73 assembly. Five major regions containing non-colinearities were identified on chromosomes 2, 3, 6, 7 and 9, and are supported by both independent genetic maps. Four additional non-colinear regions were found on the LHRF map only; they may be due to a lower density of IBM markers in those regions or to true structural rearrangements between lines. Given the array's high quality, it will be a valuable resource for maize genetics and many aspects of maize breeding. PMID:22174790

  20. A large maize (Zea mays L.) SNP genotyping array: development and germplasm genotyping, and genetic mapping to compare with the B73 reference genome.

    PubMed

    Ganal, Martin W; Durstewitz, Gregor; Polley, Andreas; Bérard, Aurélie; Buckler, Edward S; Charcosset, Alain; Clarke, Joseph D; Graner, Eva-Maria; Hansen, Mark; Joets, Johann; Le Paslier, Marie-Christine; McMullen, Michael D; Montalent, Pierre; Rose, Mark; Schön, Chris-Carolin; Sun, Qi; Walter, Hildrun; Martin, Olivier C; Falque, Matthieu

    2011-01-01

    SNP genotyping arrays have been useful for many applications that require a large number of molecular markers such as high-density genetic mapping, genome-wide association studies (GWAS), and genomic selection. We report the establishment of a large maize SNP array and its use for diversity analysis and high density linkage mapping. The markers, taken from more than 800,000 SNPs, were selected to be preferentially located in genes and evenly distributed across the genome. The array was tested with a set of maize germplasm including North American and European inbred lines, parent/F1 combinations, and distantly related teosinte material. A total of 49,585 markers, including 33,417 within 17,520 different genes and 16,168 outside genes, were of good quality for genotyping, with an average failure rate of 4% and rates up to 8% in specific germplasm. To demonstrate this array's use in genetic mapping and for the independent validation of the B73 sequence assembly, two intermated maize recombinant inbred line populations - IBM (B73×Mo17) and LHRF (F2×F252) - were genotyped to establish two high density linkage maps with 20,913 and 14,524 markers respectively. 172 mapped markers were absent in the current B73 assembly and their placement can be used for future improvements of the B73 reference sequence. Colinearity of the genetic and physical maps was mostly conserved with some exceptions that suggest errors in the B73 assembly. Five major regions containing non-colinearities were identified on chromosomes 2, 3, 6, 7 and 9, and are supported by both independent genetic maps. Four additional non-colinear regions were found on the LHRF map only; they may be due to a lower density of IBM markers in those regions or to true structural rearrangements between lines. Given the array's high quality, it will be a valuable resource for maize genetics and many aspects of maize breeding.

  1. Assessment of DNA degradation induced by thermal and UV radiation processing: implications for quantification of genetically modified organisms.

    PubMed

    Ballari, Rajashekhar V; Martin, Asha

    2013-12-01

    DNA quality is an important parameter for the detection and quantification of genetically modified organisms (GMO's) using the polymerase chain reaction (PCR). Food processing leads to degradation of DNA, which may impair GMO detection and quantification. This study evaluated the effect of various processing treatments such as heating, baking, microwaving, autoclaving and ultraviolet (UV) irradiation on the relative transgenic content of MON 810 maize using pRSETMON-02, a dual target plasmid as a model system. Amongst all the processing treatments examined, autoclaving and UV irradiation resulted in the least recovery of the transgenic (CaMV 35S promoter) and taxon-specific (zein) target DNA sequences. Although a profound impact on DNA degradation was seen during the processing, DNA could still be reliably quantified by Real-time PCR. The measured mean DNA copy number ratios of the processed samples were in agreement with the expected values. Our study confirms the premise that the final analytical value assigned to a particular sample is independent of the degree of DNA degradation since the transgenic and the taxon-specific target sequences possessing approximately similar lengths degrade in parallel. The results of our study demonstrate that food processing does not alter the relative quantification of the transgenic content provided the quantitative assays target shorter amplicons and the difference in the amplicon size between the transgenic and taxon-specific genes is minimal.

  2. Development of sampling approaches for the determination of the presence of genetically modified organisms at the field level.

    PubMed

    Sustar-Vozlic, Jelka; Rostohar, Katja; Blejec, Andrej; Kozjak, Petra; Cergan, Zoran; Meglic, Vladimir

    2010-03-01

    In order to comply with the European Union regulatory threshold for the adventitious presence of genetically modified organisms (GMOs) in food and feed, it is important to trace GMOs from the field. Appropriate sampling methods are needed to accurately predict the presence of GMOs at the field level. A 2-year field experiment with two maize varieties differing in kernel colour was conducted in Slovenia. Based on the results of data mining analyses and modelling, it was concluded that spatial relations between the donor and receptor field were the most important factors influencing the distribution of outcrossing rate (OCR) in the field. The approach for estimation fitting function parameters in the receptor (non-GM) field at two distances from the donor (GM) field (10 and 25 m) for estimation of the OCR (GMO content) in the whole receptor field was developed. Different sampling schemes were tested; a systematic random scheme in rows was proposed to be applied for sampling at the two distances for the estimation of fitting function parameters for determination of OCR. The sampling approach had already been validated with some other OCR data and was practically applied in the 2009 harvest in Poland. The developed approach can be used for determination of the GMO presence at the field level and for making appropriate labelling decisions. The importance of this approach lies in its possibility to also address other threshold levels beside the currently prescribed labelling threshold of 0.9% for food and feed.

  3. A rapid method for detection of genetically modified organisms based on magnetic separation and surface-enhanced Raman scattering.

    PubMed

    Guven, Burcu; Boyacı, İsmail Hakkı; Tamer, Ugur; Çalık, Pınar

    2012-01-07

    In this study, a new method combining magnetic separation (MS) and surface-enhanced Raman scattering (SERS) was developed to detect genetically modified organisms (GMOs). An oligonucleotide probe which is specific for 35 S DNA target was immobilized onto gold coated magnetic nanospheres to form oligonucleotide-coated nanoparticles. A self assembled monolayer was formed on gold nanorods using 5,5'-dithiobis (2-nitrobenzoic acid) (DTNB) and the second probe of the 35 S DNA target was immobilized on the activated nanorod surfaces. Probes on the nanoparticles were hybridized with the target oligonucleotide. Optimization parameters for hybridization were investigated by high performance liquid chromatography. Optimum hybridization parameters were determined as: 4 μM probe concentration, 20 min immobilization time, 30 min hybridization time, 55 °C hybridization temperature, 750 mM buffer salt concentration and pH: 7.4. Quantification of the target concentration was performed via SERS spectra of DTNB on the nanorods. The correlation between the target concentration and the SERS signal was found to be linear within the range of 25-100 nM. The analyses were performed with only one hybridization step in 40 min. Real sample analysis was conducted using Bt-176 maize sample. The results showed that the developed MS-SERS assay is capable of detecting GMOs in a rapid and selective manner.

  4. Effects of genetically modified herbicide-tolerant cropping systems on weed seedbanks in two years of following crops.

    PubMed

    Firbank, L G; Rothery, P; May, M J; Clark, S J; Scott, R J; Stuart, R C; Boffey, C W H; Brooks, D R; Champion, G T; Haughton, A J; Hawes, C; Heard, M S; Dewar, A M; Perry, J N; Squire, G R

    2006-03-22

    The Farm Scale Evaluations (FSEs) showed that genetically modified herbicide-tolerant (GMHT) cropping systems could influence farmland biodiversity because of their effects on weed biomass and seed production. Recently published results for winter oilseed rape showed that a switch to GMHT crops significantly affected weed seedbanks for at least 2 years after the crops were sown, potentially causing longer-term effects on other taxa. Here, we seek evidence for similar medium-term effects on weed seedbanks following spring-sown GMHT crops, using newly available data from the FSEs. Weed seedbanks following GMHT maize were significantly higher than following conventional varieties for both the first and second years, while by contrast, seedbanks following GMHT spring oilseed rape were significantly lower over this period. Seedbanks following GMHT beet were smaller than following conventional crops in the first year after the crops had been sown, but this difference was much reduced by the second year for reasons that are not clear. These new data provide important empirical evidence for longer-term effects of GMHT cropping on farmland biodiversity.

  5. Genetic studies on cytoplasmic male sterility in maize. Progress report, April 15, 1990--April 14, 1992

    SciTech Connect

    Laughnan, J.R.

    1992-05-01

    Our research concerns the basic mechanisms of cytoplasmic male sterility (CMS) and fertility restoration in maize. The molecular determination of CMS is in the DNA of the mitochondria (mtDNA) but specific nuclear restorer-of-fertility (Rf) genes can overrule the male-sterile effect of the cytoplasm. Our approach to the study of the Rf genes is threefold. We are attempting to tag the cms-S Rf genes and the cms-T Rf2 gene with controlling elements (CEs). Since we have identified a number of spontaneous Rf genes for cms-S and have demonstrated that they are themselves transposable, we are also searching for cases in which an Rf gene is inserted into a wild-type gene. The other aspect of our research involves the nuclear control over the organization of the mitochondrial genome. We found that the changes in mtDNA organization upon cytoplasmic reversion to fertility were characteristic of the nuclear background in which the reversion event occurred. We have investigated whether these differences are a reflection of differences in the organization of the mtDNA genome before reversion.

  6. Detection and traceability of genetically modified organisms in the food production chain.

    PubMed

    Miraglia, M; Berdal, K G; Brera, C; Corbisier, P; Holst-Jensen, A; Kok, E J; Marvin, H J P; Schimmel, H; Rentsch, J; van Rie, J P P F; Zagon, J

    2004-07-01

    Both labelling and traceability of genetically modified organisms are current issues that are considered in trade and regulation. Currently, labelling of genetically modified foods containing detectable transgenic material is required by EU legislation. A proposed package of legislation would extend this labelling to foods without any traces of transgenics. These new legislations would also impose labelling and a traceability system based on documentation throughout the food and feed manufacture system. The regulatory issues of risk analysis and labelling are currently harmonised by Codex Alimentarius. The implementation and maintenance of the regulations necessitates sampling protocols and analytical methodologies that allow for accurate determination of the content of genetically modified organisms within a food and feed sample. Current methodologies for the analysis of genetically modified organisms are focused on either one of two targets, the transgenic DNA inserted- or the novel protein(s) expressed- in a genetically modified product. For most DNA-based detection methods, the polymerase chain reaction is employed. Items that need consideration in the use of DNA-based detection methods include the specificity, sensitivity, matrix effects, internal reference DNA, availability of external reference materials, hemizygosity versus homozygosity, extrachromosomal DNA, and international harmonisation. For most protein-based methods, enzyme-linked immunosorbent assays with antibodies binding the novel protein are employed. Consideration should be given to the selection of the antigen bound by the antibody, accuracy, validation, and matrix effects. Currently, validation of detection methods for analysis of genetically modified organisms is taking place. In addition, new methodologies are developed, including the use of microarrays, mass spectrometry, and surface plasmon resonance. Challenges for GMO detection include the detection of transgenic material in materials

  7. Genome-wide association study dissects the genetic architecture of oil biosynthesis and accumulation in maize kernel

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A Genome Wide Association Study (GWAS) on a population of 368 maize inbreds with 1.06 million SNPs was performed and identified 74 highly significantly associated genes influencing maize kernel oil content and fatty acid composition. To validate these findings, three biparental linkage mapping popul...

  8. Genetic relationships and structure among open pollinated maize varieties adapted to eastern and southern Africa using microsatellite markers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The International Maize and Wheat Improvement Center (CIMMYT), in collaboration with the national agricultural systems (NARS) in sub-Saharan Africa (SSA), have developed various stress-tolerant and more nutritious open-pollinated varieties (OPVs) of maize that are suitable for smallholder farmers’ g...

  9. ZmCCT and the genetic basis of day-length adaptation underlying the postdomestication spread of maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Teosinte, the progenitor of maize, is restricted to tropical environments in Mexico and Central America. The pre-Columbian spread of maize from its center of origin in tropical Southern Mexico to the higher latitudes of the Americas required post-domestication selection for adaptation to longer dayl...

  10. Genetically Modified Crops and Nuisance: Exploring the Role of Precaution in Private Law

    ERIC Educational Resources Information Center

    Craik, Neil; Culver, Keith; Siebrasse, Norman

    2007-01-01

    This article critically considers calls for the precautionary principle to inform judicial decision making in a private law context in light of the Hoffman litigation, where it is alleged that the potential for genetic contamination from genetically modified (GM) crops causes an unreasonable interference with the rights of organic farmers to use…

  11. [Questions safety and tendency of using genetically modified microorganisms in food, food additives and food derived].