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1

PCR detection of genetically modified soya and maize in foodstuffs  

Microsoft Academic Search

The detection of genetically modified foodstuffs is becoming both a food sales and legal necessity. This study reports a rapid DNA extraction\\/PCR-based method for the detection of genetically modified soya (GMS) and maize (GMM) in mixed samples of transgenic and unmodified soybeans and maize kernels, and a variety of processed samples including soya flour, soya protein isolates, extruded defatted soya,

Carolyn D. Hurst; Angus Knight; Ian J. Bruce

1999-01-01

2

Investigations on Genetically Modified Maize (Bt-Maize) in Pig Nutrition: Fattening Performance and Slaughtering Results  

Microsoft Academic Search

A grower finisher performance trial with forty-eight pigs was designed to compare the growth performance of pigs fed diets containing either genetically modified (GM) Bt-maize (NX6262) or its parental maize (Prelude) line. During the experiment, the pigs were fed with a grower and a finisher diet both containing 70% maize investigated in a previously study which showed that they contained

T. Reuter; Karen Aulrich; A. Berk

2002-01-01

3

Unconventional P-35S sequence identified in genetically modified maize.  

PubMed

The Cauliflower Mosaic Virus 35S promoter sequence, CaMV P-35S, is one of several commonly used genetic targets to detect genetically modified maize and is found in most GMOs. In this research we report the finding of an alternative P-35S sequence and its incidence in GM maize marketed in Jordan. The primer pair normally used to amplify a 123 bp DNA fragment of the CaMV P-35S promoter in GMOs also amplified a previously undetected alternative sequence of CaMV P-35S in GM maize samples which we term V3. The amplified V3 sequence comprises 386 base pairs and was not found in the standard wild-type maize, MON810 and MON 863 GM maize. The identified GM maize samples carrying the V3 sequence were found free of CaMV when compared with CaMV infected brown mustard sample. The data of sequence alignment analysis of the V3 genetic element showed 90% similarity with the matching P-35S sequence of the cauliflower mosaic virus isolate CabbB-JI and 99% similarity with matching P-35S sequences found in several binary plant vectors, of which the binary vector locus JQ693018 is one example. The current study showed an increase of 44% in the incidence of the identified 386 bp sequence in GM maize sold in Jordan's markets during the period 2009 and 2012. PMID:24495911

Al-Hmoud, Nisreen; Al-Husseini, Nawar; Ibrahim-Alobaide, Mohammed A; Kübler, Eric; Farfoura, Mahmoud; Alobydi, Hytham; Al-Rousan, Hiyam

2014-01-01

4

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

PubMed

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. PMID:21975255

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

2010-01-01

5

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

PubMed

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. PMID:18298063

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

2008-03-26

6

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

PubMed

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. PMID:11829636

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

2002-02-13

7

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

PubMed

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. PMID:23904260

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

2013-10-01

8

Detection of genetically modified maize and soybean in feed samples.  

PubMed

Despite the controversy about genetically modified (GM) plants, they are still incrementally cultivated. In recent years, many food and feed products produced by genetic engineering technology have appeared on store shelves. Controlling the production and legal presentation of GM crops are very important for the environment and human health, especially in terms of long-term consumption. In this study, 11 kinds of feed obtained from different regions of Turkey were used for genetic analysis based on foreign gene determination. All samples were screened by conventional polymerase chain reaction (PCR) technique for widely used genetic elements; cauliflower mosaic virus 35S promoter (CaMV35S promoter), and nopaline synthase terminator (T-NOS) sequences for GM plants. After determination of GM plant-containing samples, nested PCR and conventional PCR analysis were performed to find out whether the samples contained Bt176 or GTS-40-3-2 for maize and soy, respectively. As a result of PCR-based GM plant analysis, all samples were found to be transgenic. Both 35S- and NOS-containing feed samples or potentially Bt176-containing samples, in other words, were analyzed with Bt176 insect resistant cryIAb gene-specific primers via nested PCR. Eventually, none of them were found Bt176-positive. On the other hand, when we applied conventional PCR to the same samples with the herbicide resistance CTP4-EPSPS construct-specific primers for transgenic soy variety GTS-40-3-2, we found that all samples were positive for GTS-40-3-2. PMID:24634172

Meriç, S; Cak?r, O; Turgut-Kara, N; Ar?, S

2014-01-01

9

Monitoring of MON810 genetically modified maize in foods in Brazil from 2005 to 2007  

Microsoft Academic Search

Regulations for the use and labeling of genetically modified (GM) products and derived ingredients were implemented in Brazil in 2003. In 2008, GM maize line MON810 was approved for commercialization in Brazil; nevertheless, maize Bt11, Bt176 and MON810 were found in Brazilian market products sold in 2000 and 2001. Nested polymerase chain reaction (PCR) method was employed to monitor the

Andréia Zilio Dinon; Jaqueline Elis de Melo; Ana Carolina Maisonnave Arisi

2008-01-01

10

[Medical and biological safety assessment of genetically modified maize strain MIR604].  

PubMed

The results of toxicologo-hygienic examinations, which were conducted within the framework of integrated medical and biological assessment of genetically modified rootworm Diabrotica spp.-protected maize event MIR604, are presented. Analysis of morphological, hematological, biochemical parameters and system (sensitive) biomarkers has not confirmed any toxic effect of maize event MIR604. PMID:19514339

Tutel'ian, V A; Gapparov, M M G; Avren'eva, L I; Aksiuk, I N; Guseva, G V; Kravchenko, L V; L'vova, L S; Saprykin, V P; Tyshko, N V; Chernysheva, O N

2009-01-01

11

5'Nuclease PCR for quantitative event-specific detection of the genetically modified Mon810 MaisGard maize  

Microsoft Academic Search

Genetically modified maize is grown extensively in the world today. MaisGard (Monsanto, Yieldgard in the USA) is a genetically modified maize harbouring the Mon810 transformation event. European Community legislation requires that genetically modified organisms (GMOs) be approved before they are placed on the market. Labelling is required when more than 1% of any ingredient of a food originates from a

Askild Holck; Marc Vaïtilingom; Luc Didierjean; Knut Rudi

2002-01-01

12

Presence of genetically modified maize and soy in food products sold commercially in Brazil from 2000 to 2005  

Microsoft Academic Search

Qualitative and quantitative polymerase chain reaction-based methods to detect genetically modified soy (RoundupReady™ soy) and maize (Bt176 Maximizer™ maize, Bt11 maize, MON810 YieldGard™ corn, T25 LibertyLink™ maize) were applied to processed foods sold commercially in Brazil. From 2000 to 2005, 100 food products containing maize and 100 food products containing soy were analysed every single year. The presence of genetically

Ralf Greiner; Ursula Konietzny

2008-01-01

13

DETECTION OF GENETICALLY MODIFIED MAIZE FOOD PRODUCTS BY THE POLYMERASE CHAIN REACTION DETECCIÓN DE PRODUCTOS DE MAIZ GENETICAMENTE MODIFICADOS POR LA REACCIÓN EN CADENA DE LA POLIMERASA  

Microsoft Academic Search

A polymerase chain reaction (PCR) was applied to detect genetically modified (GM) maize and soybean food product, using specific 35S promoter primers for inserted chimerical genes in maize or soybean. The PCR detected food products that include ingredients obtained from GMOs in maize grains and flour, as well as processed in foods such as tortillas (Mexican crepe), corn chips, corn

A. Mendoza; S. Fernández; M. A. Cruz; M. A. Rodríguez-Perez; D. Resendez-Perez; H. A. Barrera Saldaña

2006-01-01

14

[Medical and biological safety assessment of genetically modified maize event MIR604].  

PubMed

There are presented the results of genotoxicologic, immunologic and allergologic examinations which were conducted within the framework of integrated medical and biological assessment of genetically modified rootworm Diabrotica spp.-protected maize event MIR604. Analysis of damages of DNA and structural chromosome aberrations, assessment of the allergenic potential and immunoreactive properties has not confirmed any genotoxic, allergenic and immunotoxic effect of maize event MIR604. PMID:19514340

Tyshko, N V; Britsina, M V; Gmoshinski?, I V; Zhanataev, A K; Zakharova, N S; Zorin, S N; Mazo, V K; Ozeretskovskaia, M N; Semenov, B F

2009-01-01

15

DETECTION OF GENETICALLY MODIFIED MAIZE BY PCR AND CAPILLARY GEL ELECTROPHORESIS (CGE) USING UNCOATED COLUMNS  

Microsoft Academic Search

In this work, analysis of genetically modified insect- resistant Bt maize is demostrated by combining amplification of a DNA fragment by PCR and subsequent detection by Capillary Gel Electrophoresis (CGE). A new CGE method is developed that allows obtaining reproducible separations of DNA fragments using bare fused silica capillaries. The method combines a washing routine of the column with 0.1

Virginia García-Cañas; Ramón González; Alejandro Cifuentes

16

Evaluation of modified PCR quantitation of genetically modified maize and soybean using reference molecules: interlaboratory study.  

PubMed

Real-time polymerase chain reaction (PCR)-based quantitative methods were previously developed and validated for genetically modified (GM) maize or soy. In this study, the quantification step of the validated methods was modified, and an interlaboratory study was conducted. The modification included the introduction of the PCR system SSIIb 3 instead of SSIIb 1 for the detection of the taxon-specific sequence of maize, as well as the adoption of colE1 as a carrier included in a reference plasmid solution as a replacement for salmon testis. The interlaboratory study was conducted with the ABI PRISM 7700 and consisted of 2 separate stages: (1) the measurement of conversion factor (Cf) value, which is the ratio of recombinant DNA (r-DNA) sequence to taxon-specific sequence in each genuine GM seed, and (2) the quantification of blind samples. Additionally, Cf values of other instruments, such as the ABI PRISM 7900 and the ABI PRISM 7000, were measured in a multilaboratory trial. After outlier laboratories were eliminated, the repeatability and reproducibility for 5.0% samples were <15.8 and 20.6%, respectively. The quantitation limits of these methods were 0.5% for Bt11, T25, and MON810, and 0.1% for GA21, Event176, and RR soy. The quantitation limits, trueness, and precision of the current modified methods were equivalent to those of the previous methods. Therefore, it was concluded that the modified methods would be a suitable replacement for the validated methods. PMID:19382580

Kodama, Takashi; Kuribara, Hideo; Minegishi, Yasutaka; Futo, Satoshi; Watai, Masatoshi; Sawada, Chihiro; Watanabe, Takahiro; Akiyama, Hiroshi; Maitani, Tamio; Teshima, Reiko; Furui, Satoshi; Hino, Akihiro; Kitta, Kazumi

2009-01-01

17

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

PubMed

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. PMID:24250568

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

2013-01-01

18

Detection of Genetically Modified Maize in Processed Foods Sold Commercially in Iran by Qualitative PCR  

PubMed Central

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.

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

2013-01-01

19

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

PubMed

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. PMID:24804053

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

2013-11-01

20

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

PubMed Central

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.

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

2013-01-01

21

[Medical and biological safety assessment of genetically modified maize event MON 88017. Report 1. Toxicologo-hygienic examinations].  

PubMed

The results of toxicologo-hygienic examinations, which were conducted within the framework of integrated medical and biological assessment of genetically modified rootworm Diabrotica spp.--protected and glyphosate tolerant maize event MON 88017, are presented. Analysis of morphological, hematological, biochemical parameters and system (sensitive) biomarkers has not confirmed any toxic effect of maize event MON 88017. PMID:19048881

Tutel'ian, V A; Gapparov, M M; Avren'eva, L I; Aksiuk, I N; Guseva, G V; kravchenko, L V; L'vova, L S; Saprykin, V P; Tyshko, N V; Chernysheva, O N

2008-01-01

22

Growth performance and organ development in Atlantic salmon, Salmo salar L. parr fed genetically modified (GM) soybean and maize  

Microsoft Academic Search

Although the inclusion of genetically modified (GM) plants in diets fed to fish is a contentious issue, there are few empirical data. The present study addressed nutritional value and potential risks of four maize types (two traditional and two GM maize varieties) and two soy types (one traditional and one Roundup Readysoy) included at moderate levels in diets fed to

M. SANDEN; A. KROGDAHL; A. M. BAKKE-MCKELLEP; R. K. BUDDINGTON; G.-I. HEMRE

2006-01-01

23

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

PubMed

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 maizes. PMID:17199308

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

2007-01-10

24

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

PubMed

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. PMID:19902949

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

2009-12-01

25

Farm questionnaires for monitoring genetically modified crops: a case study using GM maize.  

PubMed

Monitoring is a statutory requirement for the cultivation of genetically modified (GM) crops in the European Community. Questionnaires for farmers to report on observations of effects linked with the cultivation of GM crops can form a useful part of a monitoring regime. A questionnaire for GM maize (Zea mays L.) was designed, with questions focusing on potential effects related to the GM maize grown, as well as on background information about cultivation methods and on individual field situations. In this paper we present the methodological approach of the monitoring regime, the structuring of the data, and the contents and structure of the questionnaire. The statistical requirements and background for an appropriate evaluation and interpretation of the data are described. Results of interviews made from 2001 to 2005 are also presented. It is envisaged that this approach will be developed for monitoring other cultivated GM plants and traits, and may be applicable in monitoring certain non-farmed environments. PMID:18801326

Schmidt, Kerstin; Wilhelm, Ralf; Schmidtke, Jörg; Beissner, Lutz; Mönkemeyer, Wenke; Böttinger, Petra; Sweet, Jeremy; Schiemann, Joachim

2008-01-01

26

Qualitative and quantitative detection of genetically modified maize and soy in processed foods sold commercially in Brazil by PCR-based methods  

Microsoft Academic Search

Qualitative and quantitative polymerase-chain-reaction-based methods to detect genetically modified (gm) soy (RoundupReadyTM soy) and maize (Bt176 Maximizer maize; Bt11 maize, MON810 Yield Gard corn, T25 LibertyR Link maize) were applied to processed foods sold commercially in Brazil. In total 100 foods containing maize and 100 foods containing soy were analysed in 2000 and again in 2001. In 2000, 13% of

Ralf Greiner; Ursula Konietzny; Anna L. C. H. Villavicencio

2005-01-01

27

[Medical and biological safety assessment of genetically modified maize event MON 88017. Report 2. Genotoxicologic, immunologic and allergologic examinations].  

PubMed

There are presented the results of genotoxicologic, immunologic and allergologic examinations which were conducted within the framework of integrated medical and biological assessment of genetically modified rootworm Diabrotica spp.--protected and glyphosate tolerant maize event MON 88017. Analysis of damages of DNA and structural chromosome aberrations, assessment of the allergenic potential and immunoreactive properties has not confirmed any genotoxic, allergenic and immunotoxic effect of maize event MON 88017. PMID:19048882

Tyshko, N V; Britsina, M V; Gmoshinski?, I V; Zhanataev, A K; Zakharova, N S; Zorin, S N; Mazo, V K; Semenov, B F

2008-01-01

28

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

PubMed

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. PMID:17300145

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

2007-02-21

29

Detection of airborne genetically modified maize pollen by real-time PCR.  

PubMed

The cultivation of genetically modified (GM) crops has raised numerous concerns in the European Union and other parts of the world about their environmental and economic impact. Especially outcrossing of genetically modified organisms (GMO) was from the beginning a critical issue as airborne pollen has been considered an important way of GMO dispersal. Here, we investigate the use of airborne pollen sampling combined with microscopic analysis and molecular PCR analysis as an approach to monitor GM maize cultivations in a specific area. Field trial experiments in the European Union and South America demonstrated the applicability of the approach under different climate conditions, in rural and semi-urban environment, even at very low levels of airborne pollen. The study documents in detail the sampling of GM pollen, sample DNA extraction and real-time PCR analysis. Our results suggest that this 'GM pollen monitoring by bioaerosol sampling and PCR screening' approach might represent an useful aid in the surveillance of GM-free areas, centres of origin and natural reserves. PMID:22805239

Folloni, Silvia; Kagkli, Dafni-Maria; Rajcevic, Bojan; Guimarães, Nilson C C; Van Droogenbroeck, Bart; Valicente, Fernando H; Van den Eede, Guy; Van den Bulcke, Marc

2012-09-01

30

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

PubMed

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. PMID:18561390

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

2008-06-01

31

Transgenerational effects of feeding genetically modified maize to nulliparous sows and offspring on offspring growth and health.  

PubMed

This study assessed the effect of feeding genetically modified maize expressing a truncated form of the Cry1Ab protein from Bacillus thuringiensis (Bt MON810 maize) to sows during gestation and lactation and their offspring from weaning to 115 d postweaning on offspring growth and health. After weaning at approximately 28 d of age (d 0), individually penned, mixed sex pigs (approximately 8 kg BW) from sows fed isogenic or Bt maize diets were blocked by sow treatment, sex, and BW and randomly assigned to Bt or isogenic maize diets as follows: i) isogenic maize-fed sow/isogenic maize-fed offspring (iso/iso); ii) isogenic maize-fed sow/Bt maize-fed offspring (iso/Bt); iii) Bt maize-fed sow/isogenic maize-fed offspring (Bt/iso); and iv) Bt maize-fed sow/Bt maize-fed offspring (Bt/Bt). Growth performance was recorded at intervals to harvest at approximately 105 kg BW (n=15/treatment) and blood samples were taken for biochemical analysis on d 0, 30, 70, 100, and 115 postweaning (n=10/treatment). Pigs were harvested on d 115 postweaning (n=10/treatment), and carcass weight, backfat depth, and organ weights (heart, kidney, spleen, and liver) were recorded. Kidney, liver, lymph nodes, and small intestine were collected for histological analysis. Offspring from Bt maize-fed sows were heavier than offspring from isogenic maize-fed sows on d 30 (P<0.05), 100 (P<0.05), and 115 postweaning (P<0.05) and had greater overall ADG (P<0.05). Overall ADFI was greater for offspring from sows fed Bt maize (P<0.05) and for Bt maize-fed pigs (P<0.05). Offspring from Bt maize-fed sows had greater carcass (P<0.05) and lighter spleen (P<0.05) weights. Dressing percentage was greater for Bt maize-fed pigs than isogenic maize-fed pigs (P<0.05), and livers were lighter for pigs in the Bt/Bt group than pigs in the iso/Bt or Bt/iso group (P<0.05). Offspring from Bt maize-fed sows also had greater duodenal crypt depths (P<0.05) and lower villus height/crypt depth ratios (P<0.05). No pathology was observed in the organs, and serum biochemistry values generally remained within normal limits and no overall differences were observed, with the exception of overall ? glutamyltransferase, which was less for pigs on the Bt/Bt treatment than pigs on the iso/Bt and Bt/iso treatments. These results indicate that transgenerational consumption of Bt maize diets is not detrimental to pig growth and health. PMID:23097397

Buzoianu, S G; Walsh, M C; Rea, M C; Cassidy, J P; Ryan, T P; Ross, R P; Gardiner, G E; Lawlor, P G

2013-01-01

32

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

PubMed

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. PMID:24471096

Moon, Gi-Seong; Shin, Weon-Sun

2012-12-01

33

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

PubMed

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. PMID:19609704

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

2010-04-01

34

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

Microsoft Academic Search

To investigate the relative degradation and fragmentation pattern of the recombinant Cry1Ab protein from genetically modified\\u000a (GM) maize MON810 throughout the gastrointestinal tract (GIT) of dairy cows, a 25 months GM maize feeding study was conducted\\u000a on 36 lactating Bavarian Fleckvieh cows allocated into two groups (18 cows per group) fed diets containing either GM maize\\u000a MON810 or nearly isogenic non-GM

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

2010-01-01

35

Detection of six genetically modified maize lines using optical thin-film biosensor chips.  

PubMed

As more and more genetically modified organisms (GMO) are commercialized, efficient and inexpensive assays are required for their quick detection. An event-specific detection strategy based on the unique and specific sequences of integration junctions is useful because of its high specificity. This study developed a system for detecting six GM maize lines (Bt11, Bt176, GA21, MON810, NK603, and T25) using optical silicon thin-film biosensor chips. Aldehyde-labeled probes were arrayed and covalently attached to a hydrazine-derivatized chip surface. Biotinylated PCR amplicons were then hybridized with the probes. After washing and brief incubation with an anti-biotin IgG horseradish peroxidase conjugate and a precipitable horseradish peroxidase substrate, biotinylated PCR amplicons perfectly matched with the probes can be visualized by the color change on the chip surface (gold to blue/purple). This assay is extremely robust, exhibits high sensitivity and specificity, and is flexible from low through moderate to high throughput. PMID:20614904

Bai, Sulan; Zhang, Jie; Li, Shucheng; Chen, Haodong; Terzaghi, William; Zhang, Xin; Chi, Xiurong; Tian, Jin; Luo, Hongxia; Huang, Wensheng; Chen, Ying; Zhang, Yaochuan

2010-08-11

36

Representative taxa in field trials for environmental risk assessment of genetically modified maize.  

PubMed

When assessing the benefits and risks of transgenic crops, one consideration is their relative effects on non-target arthropod (NTA) abundance and functions within agroecosystems. Several laboratory and field trials have been conducted in Spain since the late 1990s to assess this issue. A consideration in the design of field trials is whether it is necessary to sample most NTAs living in the crop or only representative taxa that perform main ecological functions and have a good capacity to detect small changes in their abundance. Small changes in the field abundance of an effective representative taxon should be detectable using standard experimental protocols. The ability of a species to reveal differences across treatments may be analysed by examining the detectable treatment effects for surveyed non-target organisms. Analysis of data from several NTAs recorded in 14 field trials conducted over 10 years using complete block designs allowed us to select a number of representative taxa capable of detecting changes in the density or activity of arthropod herbivores, predators, parasitoids and decomposers in transgenic and non-transgenic maize varieties. The most suitable NTA as representative taxa (with detectable treatment effects below 50%) included leafhoppers among arthropod herbivores, Orius spp., Araneae, and Carabidae among predators, chalcidids, particularly the family Mymaridae, among parasitoids and Chloropidae as decomposer. Details of sampling techniques for each sampled taxa and their advantages and disadvantages are discussed. It is concluded that abundance of taxa is the most influential factor determining their capacity to detect changes caused by genetically modified varieties. PMID:23987801

Albajes, R; Lumbierres, B; Pons, X; Comas, J

2013-12-01

37

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

PubMed Central

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.

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

2006-01-01

38

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

PubMed Central

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.

Szenasi, Agnes; Palinkas, Zoltan; Zalai, Mihaly; Schmitz, Oswald J.; Balog, Adalbert

2014-01-01

39

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

PubMed

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. PMID:24937207

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

2014-01-01

40

Interlaboratory validation of an event-specific real time polymerase chain reaction detection method for genetically modified DAS59132 maize.  

PubMed

A real-time polymerase chain reaction (PCR) method specific for genetically modified (GM) maize event DAS59132 (E32) was adapted for qualitative detection of low level presence of E32. The method was validated by a collaborative trial with eight participating Japanese laboratories. Sensitivity was assessed with three different samples of corn flour fortified to 0%, 0.05% and 0.1% (w/w) E32 respectively. In addition, a 0.01% E32 DNA solution was used. The detection limit with DNA solution was estimated to be approximately 0.01%. In conclusion, the results of the study confirmed this real-time PCR method as a reliable tool for qualitative detection of E32 maize. PMID:20453456

Akiyama, Hiroshi; Sakata, Kozue; Spiegelhalter, Frank; Furui, Satoshi; Nakashima, Akie; Kitta, Kazumi; Teshima, Reiko

2010-01-01

41

Screening of genetically modified organisms and specific detection of Bt176 maize in flours and starches by PCR-enzyme linked immunosorbent assay  

Microsoft Academic Search

Polymerase chain reaction (PCR)-enzyme linked immunosorbent assays (ELISAs) targeting either the 35S promoter or the Bt176 specific junction sequence were developed to screen for the presence of genetically modified organisms (GMOs) and specifically detect Bt176 maize in flours and starches. Two additional PCR-ELISA assays were developed to validate the results: one, based on the detection of the maize alcohol dehydrogenase

Laetitia Petit; Fabienne Baraige; Anne-Marie Balois; Yves Bertheau; Patrick Fach

2003-01-01

42

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

PubMed

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. PMID:23124960

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

2013-03-01

43

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

Microsoft Academic Search

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 ampli- fiable from rumen fluid sampled 5 h after feeding maize grains. The

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

2003-01-01

44

Sequence-Based Analysis of the Intestinal Microbiota of Sows and Their Offspring Fed Genetically Modified Maize Expressing a Truncated Form of Bacillus thuringiensis Cry1Ab Protein (Bt Maize)  

PubMed Central

The aim was to investigate transgenerational effects of feeding genetically modified (GM) maize expressing a truncated form of Bacillus thuringiensis Cry1Ab protein (Bt maize) to sows and their offspring on maternal and offspring intestinal microbiota. Sows were assigned to either non-GM or GM maize dietary treatments during gestation and lactation. At weaning, offspring were assigned within sow treatment to non-GM or GM maize diets for 115 days, as follows: (i) non-GM maize-fed sow/non-GM maize-fed offspring (non-GM/non-GM), (ii) non-GM maize-fed sow/GM maize-fed offspring (non-GM/GM), (iii) GM maize-fed sow/non-GM maize-fed offspring (GM/non-GM), and (iv) GM maize-fed sow/GM maize-fed offspring (GM/GM). Offspring of GM maize-fed sows had higher counts of fecal total anaerobes and Enterobacteriaceae at days 70 and 100 postweaning, respectively. At day 115 postweaning, GM/non-GM offspring had lower ileal Enterobacteriaceae counts than non-GM/non-GM or GM/GM offspring and lower ileal total anaerobes than pigs on the other treatments. GM maize-fed offspring also had higher ileal total anaerobe counts than non-GM maize-fed offspring, and cecal total anaerobes were lower in non-GM/GM and GM/non-GM offspring than in those from the non-GM/non-GM treatment. The only differences observed for major bacterial phyla using 16S rRNA gene sequencing were that fecal Proteobacteria were less abundant in GM maize-fed sows prior to farrowing and in offspring at weaning, with fecal Firmicutes more abundant in offspring. While other differences occurred, they were not observed consistently in offspring, were mostly encountered for low-abundance, low-frequency bacterial taxa, and were not associated with pathology. Therefore, their biological relevance is questionable. This confirms the lack of adverse effects of GM maize on the intestinal microbiota of pigs, even following transgenerational consumption.

Buzoianu, Stefan G.; Walsh, Maria C.; Rea, Mary C.; Quigley, Lisa; O'Sullivan, Orla; Cotter, Paul D.; Ross, R. Paul; Lawlor, Peadar G.

2013-01-01

45

Sequence-based analysis of the intestinal Microbiota of sows and their offspring fed genetically modified maize expressing a truncated form of Bacillus thuringiensis Cry1Ab protein (Bt Maize).  

PubMed

The aim was to investigate transgenerational effects of feeding genetically modified (GM) maize expressing a truncated form of Bacillus thuringiensis Cry1Ab protein (Bt maize) to sows and their offspring on maternal and offspring intestinal microbiota. Sows were assigned to either non-GM or GM maize dietary treatments during gestation and lactation. At weaning, offspring were assigned within sow treatment to non-GM or GM maize diets for 115 days, as follows: (i) non-GM maize-fed sow/non-GM maize-fed offspring (non-GM/non-GM), (ii) non-GM maize-fed sow/GM maize-fed offspring (non-GM/GM), (iii) GM maize-fed sow/non-GM maize-fed offspring (GM/non-GM), and (iv) GM maize-fed sow/GM maize-fed offspring (GM/GM). Offspring of GM maize-fed sows had higher counts of fecal total anaerobes and Enterobacteriaceae at days 70 and 100 postweaning, respectively. At day 115 postweaning, GM/non-GM offspring had lower ileal Enterobacteriaceae counts than non-GM/non-GM or GM/GM offspring and lower ileal total anaerobes than pigs on the other treatments. GM maize-fed offspring also had higher ileal total anaerobe counts than non-GM maize-fed offspring, and cecal total anaerobes were lower in non-GM/GM and GM/non-GM offspring than in those from the non-GM/non-GM treatment. The only differences observed for major bacterial phyla using 16S rRNA gene sequencing were that fecal Proteobacteria were less abundant in GM maize-fed sows prior to farrowing and in offspring at weaning, with fecal Firmicutes more abundant in offspring. While other differences occurred, they were not observed consistently in offspring, were mostly encountered for low-abundance, low-frequency bacterial taxa, and were not associated with pathology. Therefore, their biological relevance is questionable. This confirms the lack of adverse effects of GM maize on the intestinal microbiota of pigs, even following transgenerational consumption. PMID:24096421

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

2013-12-01

46

Quantitative competitive PCR for the detection of genetically modified soybean and maize  

Microsoft Academic Search

The surveillance of food labelling concerning genetically modified organisms (GMOs) requires DNA-based analytical techniques.\\u000a Present assay systems allow the detection of GMO in food; however, they do not permit their quantitation. In this study, we\\u000a report the development of quantitative competitive polymerase chain reaction (QC-PCR) systems for the detection and quantitation\\u000a of the Roundup Ready soybean (RRS) and the Maximizer

Edgar Studer; Claudio Rhyner; Jürg Lüthy; P. Hübner

1998-01-01

47

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

Microsoft Academic Search

Quantitative analysis of genetically modified (GM) foods requires estimation of the amount of the transgenic event relative\\u000a to an endogenous gene. Regulatory authorities in the European Union (EU) have defined the labelling threshold for GM food\\u000a on the copy number ratio between the transgenic event and an endogenous gene. Real-time polymerase chain reaction (PCR) is\\u000a currently being used for quantification

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

2010-01-01

48

Environmental impact of herbicide regimes used with genetically modified herbicide-resistant maize  

Microsoft Academic Search

With the potential advent of genetically modified herbicide-resistant (GMHR) crops in the European Union, changes in patterns\\u000a of herbicide use are predicted. Broad-spectrum, non-selective herbicides used with GMHR crops are expected to substitute for\\u000a a set of currently used herbicides, which might alter the agro-environmental footprint from crop production. To test this\\u000a hypothesis, the environmental impact of various herbicide regimes

Yann Devos; Mathias Cougnon; Sofie Vergucht; Robert Bulcke; Geert Haesaert; Walter Steurbaut; Dirk Reheul

2008-01-01

49

Detection of genetically modified soya and maize: Impact of heat processing  

Microsoft Academic Search

The analysis of processed foods entails a number of complications, which negatively affect the performance of DNA based detection methods. Heat-processing methods viz. autoclaving and micro-waving, that mimic processing and manufacturing, as model unit operation systems were used to study their effect on the detection of genetically modified organisms (GMOs). This study confirms the premise that high temperature and\\/or pressure

K. R. Vijayakumar; Asha Martin; Lalitha R. Gowda; V. Prakash

2009-01-01

50

Estimating Mexican Farmers’ Valuation of Milpa Diversity and Genetically Modified Maize: A Choice Experiment Approach  

Microsoft Academic Search

The milpa is a traditional intercropping system of maize, bean, and squash. Milpas are repositories of agrobiodiversity in México, not only rich in inter- and infra-crop species diversity, but also in landraces of maize, which are building blocks for future improvements in this globally important staple crop. Even though they are still widely cultivated across México, sustainability of milpa cultivation

Ekin Birol; Eric Rayn Villalba

2006-01-01

51

Event-specific detection of seven genetically modified soybean and maizes using multiplex-PCR coupled with oligonucleotide microarray.  

PubMed

With the increasing development of genetically modified organism (GMO) detection techniques, the polymerase chain reaction (PCR) technique has been the mainstay for GMO detection. An oligonucleotide microarray is a glass chip to the surface of which an array of oligonucleotides was fixed as spots, each containing numerous copies of a sequence-specific probe that is complementary to a gene of interest. So it is used to detect ten or more targets synchronously. In this research, 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 using multiplex-PCR together with oligonucleotide microarray. A commercial GM soybean (GTS 40-3-2) and six GM maize events (MON810, MON863, Bt176, Bt11, GA21, and T25) were detected by this method. The results indicate that it is a suitable method for the identification of these GM soybean and maizes. PMID:17559227

Xu, Jia; Zhu, Shuifang; Miao, Haizhen; Huang, Wensheng; Qiu, Minyan; Huang, Yan; Fu, Xuping; Li, Yao

2007-07-11

52

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

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. PMID:22467509

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

53

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

PubMed

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. PMID:18346452

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

2008-05-15

54

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

PubMed

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. PMID:24040165

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

2013-01-01

55

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

PubMed

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. PMID:23132355

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

56

Fate of recombinant DNA and Cry1Ab protein after ingestion and dispersal of genetically modified maize in comparison to rapeseed by fallow deer (Dama dama)  

Microsoft Academic Search

Abstract The fate of recombinant,DNA in fallow deer (Dama,dama) was,investigated by,feeding a diet of isogenic or genetically modified,(GM) maize,expressing Cry1Ab protein against the European corn borer (Ostrinia nubilalis). To study the degradability of ingested DNA, polymerase chain reaction (PCR) assays were introduced to detect fragments of the endogenous, highly abundant chloroplast-specific rubisco gene, the maize-specific zein gene,and the recombinant,cry1Ab gene.

P. Guertler; R. Einspanier; B. Killermann C. Albrecht

57

Development of quantitative duplex real-time PCR method for screening analysis of genetically modified maize.  

PubMed

A duplex real-time PCR method was developed for quantitative screening analysis of GM maize. The duplex real-time PCR simultaneously detected two GM-specific segments, namely the cauliflower mosaic virus (CaMV) 35S promoter (P35S) segment and an event-specific segment for GA21 maize which does not contain P35S. Calibration was performed with a plasmid calibrant specially designed for the duplex PCR. The result of an in-house evaluation suggested that the analytical precision of the developed method was almost equivalent to those of simplex real-time PCR methods, which have been adopted as ISO standard methods for the analysis of GMOs in foodstuffs and have also been employed for the analysis of GMOs in Japan. In addition, this method will reduce both the cost and time requirement of routine GMO analysis by half. The high analytical performance demonstrated in the current study would be useful for the quantitative screening analysis of GM maize. We believe the developed method will be useful for practical screening analysis of GM maize, although interlaboratory collaborative studies should be conducted to confirm this. PMID:19602858

Oguchi, Taichi; Onishi, Mari; Minegishi, Yasutaka; Kurosawa, Yasunori; Kasahara, Masaki; Akiyama, Hiroshi; Teshima, Reiko; Futo, Satoshi; Furui, Satoshi; Hino, Akihiro; Kitta, Kazumi

2009-06-01

58

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

PubMed

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. PMID:16972302

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

2006-10-01

59

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

PubMed

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. PMID:21873818

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

60

Effect of feeding genetically modified Bt MON810 maize to ?40-day-old pigs for 110 days on growth and health indicators.  

PubMed

A total of 72 male weaned pigs were used in a 110-day study to investigate the effect of feeding genetically modified (GM) Bt MON810 maize on selected growth and health indicators. It was hypothesised that in pigs fed Bt maize, growth and health are not impacted compared with pigs fed isogenic maize-based diets. Following a 12-day basal period, pigs (10.7 ± 1.9 kg body weight (BW); ?40 days old) were blocked by weight and ancestry and randomly assigned to treatments: (1) non-GM maize diet for 110 days (non-GM), (2) GM maize diet for 110 days (GM), (3) non-GM maize diet for 30 days followed by GM maize diet up to day 110 (non-GM/GM) and (4) GM maize diet for 30 days followed by non-GM maize diet up to day 110 (GM/non-GM). BW and daily feed intake were recorded on days 0, 30, 60 and 110 (n = 15). Body composition was determined by dual energy X-ray absorptiometry (n = 10) on day 80. Following slaughter on day 110, organs and intestines were weighed and sampled for histological analysis and urine was collected for biochemical analysis (n = 10). Serum biochemistry analysis was performed on days 0, 30, 60, 100 and 110. Growth performance and serum biochemistry were analysed as repeated measures with time and treatment as main factors. The slice option of SAS was used to determine treatment differences at individual time points. There was no effect of feeding GM maize on overall growth, body composition, organ and intestinal weight and histology or serum biochemistry on days 60 and 100 and on urine biochemistry on day 110. A treatment × time interaction was observed for serum urea (SU; P < 0.05), creatinine (SC; P < 0.05) and aspartate aminotransferase (AST; P < 0.05). On day 30, SU was lower for the non-GM/GM treatment compared with the non-GM, GM and GM/non-GM treatments (P < 0.05). On day 110, SC was higher for the non-GM/GM and GM/non-GM treatments compared with non-GM and GM treatments (P < 0.05). Overall, serum total protein was lower for the GM/non-GM treatment compared with the non-GM/GM treatment (P < 0.05). The magnitude of change observed in some serum biochemical parameters did not indicate organ dysfunction and the changes were not accompanied by histological lesions. Long-term feeding of GM maize to pigs did not adversely affect growth or the selected health indicators investigated. PMID:23031560

Buzoianu, S G; Walsh, M C; Rea, M C; Cassidy, J P; Ross, R P; Gardiner, G E; Lawlor, P G

2012-10-01

61

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

PubMed

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. PMID:20088594

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

2010-02-24

62

Development of the visual loop-mediated isothermal amplification assays for seven genetically modified maize events and their application in practical samples analysis.  

PubMed

As more and more genetically modified (GM) crops are approved for commercialization and planting, the development of quick and on-spot methods for GM crops and their derivates is required. Herein, we established the polymerase chain reaction and agarose gel electrophoresis-free system for the identification of seven GM maize events (DAS-59122-7, T25, BT176, TC1507, MON810, BT11, and MON863) employing a loop-mediated isothermal amplification (LAMP) technique. The LAMP assay was performed using a set of four specific primers at 60-65 °C in less than 40 min, and the results were observed by direct visual observation. In these developed assays, the specificity targeted at each GM maize event based on the event-specific sequence was well confirmed, and the limits of detection were as low as four copies of maize haploid genomic DNA with an exception of 40 copies for MON810 assay. Furthermore, these developed assays were successfully used to test six practical samples with different GM maize events and contents (ranged from 0.0 to 2.0%). All of the results indicated that the established event-specific visual LAMP assays are more convenient, rapid, and low-cost for GM maize routine analysis. PMID:21520936

Chen, Lili; Guo, Jinchao; Wang, Qidi; Kai, Guoyin; Yang, Litao

2011-06-01

63

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

PubMed

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. PMID:18767863

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

2008-10-01

64

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

PubMed

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. PMID:16302741

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

2005-11-30

65

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

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. PMID:22165018

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

66

Results of an interlaboratory assessment of a screening method of genetically modified organisms in soy beans and maize  

Microsoft Academic Search

The preliminary results on an interlaboratory trial on the detection of genetically modified organisms (GMO) are presented. The method applied is based on the detection of modified DNA using the polymerase chain reaction (PCR) for amplification. The amplified fragments analysed are derived from the 35S promotor and the NOS terminator used for modification and are present in 26 from the

M Lipp; E Anklam; P Brodmann; K Pietsch; J Pauwels

1999-01-01

67

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

PubMed

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. PMID:15853368

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

2005-05-01

68

Interlaboratory study of qualitative PCR methods for genetically modified maize events MON810, bt11, GA21, and CaMV P35S.  

PubMed

Qualitative PCR methods for the genetically modified (GM) maize events MON810, Bt11, and GA21, and the 35S promoter (P35S) region of the cauliflower mosaic virus (CaMV) were evaluated in an interlaboratory study. Real-time PCR-based quantitative methods for these GM events using the same primer pairs had already been validated in previous studies. Fifteen laboratories in Japan participated in this interlaboratory study. Each participant extracted DNA from blind samples, performed qualitative PCR assays, and then detected the PCR products with agarose gel electrophoresis. The specificity, sensitivity, and false-negative and false-positive rates of these methods were determined with different concentrations of GM mixing samples. LODs of these methods for MON810, Bt11, GA21, and the P35S segment calculated as the amount of MON810 were 0.2, 0.2, 0.1, and 0.2% or less, respectively, indicating that the LODs of MON810, Bt11, and P35S were lower than 10 copies, and the LOD of GA21 was lower than 25 copies of maize haploid genome. The current study demonstrated that the qualitative methods would be fit for the detection and identification of these GM maize events and the P35S segment. PMID:23767360

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

2013-01-01

69

[Laboratory-performance study of the notified methods to detect genetically modified maize (CBH351) and potato (NewLeaf Plus and NewLeaf Y)].  

PubMed

To investigate the key factors affecting the reliability of the analytical results, a laboratory-performance study was attempted for the notified methods to detect genetically modified (GM) maize (CBH351) and GM potato (NewLeaf Plus and NewLeaf Y). The test samples were designed as three pairs of blind duplicates, which included 0%, 0.1% and 1.0% GM maize (CBH351) or GM potato (NewLeaf Plus or NewLeaf Y). Fourteen laboratories participated in the study. The test samples were sent to the participating laboratories along with the protocol. The data were collected from all laboratories and statistically analyzed. For the 0% sample of the CBH351 maize, one laboratory reported a false-positive result. It was considered that contamination could have occurred via the common use of equipment or tools for the test. For the 0.1% samples of the NewLeaf Plus potato or NewLeaf Y potato, on the other hand, three laboratories reported false-negative results. It was presumed that these results were due to changes of the conditions of the electrophoresis and agarose-gel staining. The other laboratories reported appropriate results. It was considered that the method employed in this study was suitable for the assessment of laboratory performance. PMID:15038109

Watanabe, Takahiro; Kasama, Kikuko; Wakui, Chiseko; Shibuya, Masaaki; Matsuki, Akihiko; Akiyama, Hiroshi; Maitani, Tamio

2003-12-01

70

Assessing the risk posed to free-living soil nematodes by a genetically modified maize expressing the insecticidal Cry3Bb1 protein.  

PubMed

Before pest-resistant genetically modified maize can be grown commercially, the risks for soil-beneficial, non-target organisms must be determined. Here, a tiered approach was used to assess the risk to free-living soil nematodes posed by maize genetically modified to express the insecticidal Cry3Bb1 protein (event Mon88017), which confers resistance towards western corn rootworm (Diabrotica virgifera; Coleoptera). The toxicity of purified Cry3Bb1 for the nematode Caenorhabditis elegans was determined using a bioassay and gene expression analysis. In addition, a soil toxicity test was used to assess the effects on C. elegans of rhizosphere soil obtained from plots of an experimental field grown with Mon88017, the near-isogenic cultivar, or either of two conventional cultivars. Finally, the indigenous nematode communities from the experimental field site with Mon88017 and from the control cultivars were analyzed. The results showed a dose-dependent inhibitory effect of Cry3Bb1 on the growth and reproduction of C. elegans, with EC50 values of 22.3 mg l?¹ and 7.9 mg l?¹, respectively. Moreover, Cry-protein-specific defense genes were found to be up-regulated in the presence of either Cry1Ab or Cry3Bb1. However, C. elegans was not affected by rhizosphere soils from Mon88017 compared to the control plots, due to the very low Cry3Bb1 concentrations, as indicated by quantitative analyses (< 1 ng g?¹ soil). Nematode abundance and diversity were essentially the same between the various maize cultivars. At the last sampling date, nematode genus composition in Bt-maize plots differed significantly from that in two of the three non-Bt cultivars, including the near-isogenic maize, but the shift in genus composition did not influence the composition of functional guilds within the nematode communities. In conclusion, the risk to free-living soil nematodes posed by Mon88017 cultivation can be regarded as low, as long as Cry3Bb1 concentrations in soil remain four orders of magnitude below the toxicity threshold. PMID:21511326

Höss, S; Nguyen, H T; Menzel, R; Pagel-Wieder, S; Miethling-Graf, R; Tebbe, C C; Jehle, J A; Traunspurger, W

2011-06-01

71

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

PubMed

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. PMID:19888668

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

2010-08-01

72

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

Microsoft Academic Search

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

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

2008-01-01

73

Detect Genetically Modified Food  

NSDL National Science Digital Library

Genetically modified foods are often in the news and widely grown in the United States. Three US government agencies (USDA, FDA, and EPA) work to regulate the introduction and production of genetically modified foods. These crops can provide agricultural, ecological and nutritional benefits, but there are also potential risks to the environment and consumers. As consumers and public interest groups around the world have become aware of these risks, there has been a call for more explicit product labeling and reliable methods for the detection of genetic modification in the foods we eat. This lab activity explores these issues by taking students through a three-part process to detect the presence of genetic modification in corn (maize) or soy food products. This lab uses PCR analysis, one of the two methods for detection of genetic modification currently approved by the European Union. For convenience, the resource is divided into five sections, all PDF files, including background, wet lab, paper lab, assessment and further reading.

Brandner, Diana

2012-12-04

74

Quantification and identification of genetically modified maize events in non-identity preserved maize samples in 2009 using an individual kernel detection system.  

PubMed

We investigated the GM maize grain content of non-identity preserved (non-IP) maize samples produced in 2009 in the USA using our individual kernel detection system, involving two multiplex qualitative PCR methods coupled to microchip electrophoresis and partially real-time PCR array analysis, to clarify how many GM event maize grains were present in the samples and which GM events frequently appeared in 2009. The average percentage and standard deviation of GM maize grains on a kernel basis in five non-IP sample lots were 81.9%±2.8%, the average percentage of single GM event grains was 46.9%, and the average percentage of stacked GM event grains was 35.0%. MON88017 grains and NK603 grains were the most frequently observed as single GM event grains. The most frequent stacked GM event grains were MON88017×MON810 grains. This study shows that our method can provide information about GM maize events present in imported maize samples on a kernel basis. PMID:23132354

Akiyama, Hiroshi; Minegishi, Yasutaka; Makiyama, Daiki; Mano, Junichi; Sakata, Kozue; Nakamura, Kosuke; Noguchi, Akio; Takabatake, Reona; Futo, Satoshi; Kondo, Kazunari; Kitta, Kazumi; Kato, Yasuo; Teshima, Reiko

2012-01-01

75

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

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. PMID:17638110

Zhang, David; Corlet, Aurélie; Fouilloux, Stephane

2008-06-01

76

The Maize Genetics and Genomics Database. The Community Resource for Access to Diverse Maize Data1  

PubMed Central

The Maize Genetics and Genomics Database (MaizeGDB) serves the maize (Zea mays) research community by making a wealth of genetics and genomics data available through an intuitive Web-based interface. The goals of the MaizeGDB project are 3-fold: to provide a central repository for public maize information; to present the data through the MaizeGDB Web site in a way that recapitulates biological relationships; and to provide an array of computational tools that address biological questions in an easy-to-use manner at the site. In addition to these primary tasks, MaizeGDB team members also serve the community of maize geneticists by lending technical support for community activities, including the annual Maize Genetics Conference and various workshops, teaching researchers to use both the MaizeGDB Web site and Community Curation Tools, and engaging in collaboration with individual research groups to make their unique data types available through MaizeGDB.

Lawrence, Carolyn J.; Seigfried, Trent E.; Brendel, Volker

2005-01-01

77

Genetic Characterization of a Core Set of a Tropical Maize Race Tuxpe?o for Further Use in Maize Improvement  

PubMed Central

The tropical maize race Tuxpeño is a well-known race of Mexican dent germplasm which has greatly contributed to the development of tropical and subtropical maize gene pools. In order to investigate how it could be exploited in future maize improvement, a panel of maize germplasm accessions was assembled and characterized using genome-wide Single Nucleotide Polymorphism (SNP) markers. This panel included 321 core accessions of Tuxpeño race from the International Maize and Wheat Improvement Center (CIMMYT) germplasm bank collection, 94 CIMMYT maize lines (CMLs) and 54 U.S. Germplasm Enhancement of Maize (GEM) lines. The panel also included other diverse sources of reference germplasm: 14 U.S. maize landrace accessions, 4 temperate inbred lines from the U.S. and China, and 11 CIMMYT populations (a total of 498 entries with 795 plants). Clustering analyses (CA) based on Modified Rogers Distance (MRD) clearly partitioned all 498 entries into their corresponding groups. No sub clusters were observed within the Tuxpeño core set. Various breeding strategies for using the Tuxpeño core set, based on grouping of the studied germplasm and genetic distance among them, were discussed. In order to facilitate sampling diversity within the Tuxpeño core, a minicore subset of 64 Tuxpeño accessions (20% of its usual size) representing the diversity of the core set was developed, using an approach combining phenotypic and molecular data. Untapped diversity represents further use of the Tuxpeño landrace for maize improvement through the core and/or minicore subset available to the maize community.

Chavez-Tovar, Victor H.; Yan, Jianbing; Taba, Suketoshi

2012-01-01

78

Random amplified polymorphic DNA analysis of genetically modified organisms  

Microsoft Academic Search

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%

Cheah Yoke-Kqueen; Son Radu

2006-01-01

79

The genetic architecture of maize height.  

PubMed

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. PMID:24514905

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

80

The Genetic Architecture Of Maize Height  

PubMed Central

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.

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.

2014-01-01

81

Detection of Genetically Modified Food  

NSDL National Science Digital Library

Genetically modified foods are often in the news and widely grown in the United States. Three US government agencies (USDA, FDA, and EPA) work to regulate the introduction and production of genetically modified foods. These crops can provide agricultural, ecological and nutritional benefits, but there are also potential risks to the environment and consumers. As consumers and public interest groups around the world have become aware of these risks, there has been a call for more explicit product labeling and reliable methods for the detection of genetic modification in the foods we eat. This lab activity explores these issues by taking students through a three-part process to detect the presence of genetic modification in corn (maize) or soy food products. This lab uses PCR analysis, one of the two methods for detection of genetic modification currently approved by the European Union.For convenience, the resource is divided into 5 sections, all pdf files, including background, wet lab,paper lab, assessment and further reading.

Brandner, Diana

2009-08-31

82

Quantitation of 35S promoter in maize DNA extracts from genetically modified organisms using real-time polymerase chain reaction, part 2: interlaboratory study.  

PubMed

The European Committee for Standardization (CEN) and the European Network of GMO Working Laboratories have proposed development of a modular strategy for stepwise validation of complex analytical techniques. When applied to the quantitation of genetically modified organisms (GMOs) in food products, the instrumental quantitation step of the technique is separately validated from the DNA extraction step to better control the sources of uncertainty and facilitate the validation of GMO-specific polymerase chain reaction (PCR) tests. This paper presents the results of an interlaboratory study on the quantitation step of the method standardized by CEN for the detection of a regulatory element commonly inserted in GMO maize-based foods. This is focused on the quantitation of P35S promoter through using the quantitative real-time PCR (QRT-PCR). Fifteen French laboratories participated in the interlaboratory study of the P35S quantitation operating procedure on DNA extract samples using either the thermal cycler ABI Prism 7700 (Applied Biosystems, Foster City, CA) or Light Cycler (Roche Diagnostics, Indianapolis, IN). Attention was focused on DNA extract samples used to calibrate the method and unknown extract samples. Data were processed according to the recommendations of ISO 5725 standard. Performance criteria, obtained using the robust algorithm, were compared to the classic data processing after rejection of outliers by the Cochran and Grubbs tests. Two laboratories were detected as outliers by the Grubbs test. The robust precision criteria gave values between the classical values estimated before and after rejection of the outliers. Using the robust method, the relative expanded uncertainty by the quantitation method is about 20% for a 1% Bt176 content, whereas it can reach 40% for a 0.1% Bt176. The performances of the quantitation assay are relevant to the application of the European regulation, which has an accepted tolerance interval of about +/-50%. These data were fitted to a power model (r2 = 0.96). Thanks to this model, it is possible to propose an estimation of uncertainty of the QRT-PCR quantitation step and an uncertainty budget depending on the analytical conditions. PMID:15859084

Feinberg, Max; Fernandez, Sophie; Cassard, Sylvanie; Bertheau, Yves

2005-01-01

83

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

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. PMID:21504143

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

2011-05-25

84

Genetically transformed maize plants from protoplasts.  

PubMed

Genetically transformed maize plants were obtained from protoplasts treated with recombinant DNA. Protoplasts that were digested from embryogenic cell suspension cultures of maize inbred A188 were combined with plasmid DNA containing a gene coding for neomycin phosphotransferase (NPT II) next to the 35S promoter region of cauliflower mosaic virus. A high voltage electrical pulse was applied to the protoplasts, which were then grown on filters placed over feeder layers of maize suspension cells (Black Mexican Sweet) and selected for growth in the presence of kanamycin. Selected cell lines showed NPT II activity. Plants were regenerated from transformed cell lines and grown to maturity. Southern analysis of DNA extracted from callus and plants indicated the presence of the NPT II gene. PMID:2832947

Rhodes, C A; Pierce, D A; Mettler, I J; Mascarenhas, D; Detmer, J J

1988-04-01

85

MaizeGDB, the community database for maize genetics and genomics  

PubMed Central

The Maize Genetics and Genomics Database (MaizeGDB) is a central repository for maize sequence, stock, phenotype, genotypic and karyotypic variation, and chromosomal mapping data. In addition, MaizeGDB provides contact information for over 2400 maize cooperative researchers, facilitating interactions between members of the rapidly expanding maize community. MaizeGDB represents the synthesis of all data available previously from ZmDB and from MaizeDB—databases that have been superseded by MaizeGDB. MaizeGDB provides web-based tools for ordering maize stocks from several organizations including the Maize Genetics Cooperation Stock Center and the North Central Regional Plant Introduction Station (NCRPIS). Sequence searches yield records displayed with embedded links to facilitate ordering cloned sequences from various groups including the Maize Gene Discovery Project and the Clemson University Genomics Institute. An intuitive web interface is implemented to facilitate navigation between related data, and analytical tools are embedded within data displays. Web-based curation tools for both designated experts and general researchers are currently under development. MaizeGDB can be accessed at http://www.maizegdb.org/.

Lawrence, Carolyn J.; Dong, Qunfeng; Polacco, Mary L.; Seigfried, Trent E.; Brendel, Volker

2004-01-01

86

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

PubMed

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. PMID:22709787

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

2012-09-01

87

Genetic and environmental influence on maize kernel proteome.  

PubMed

Comparative targeted compositional analysis is currently an important element in the safety assessment of genetically modified plants. Profiling methods have been suggested as nontargeted tools to improve the detection of possible unintended effects. In this study, the capability of 2-dimensional electrophoresis to detect significant differences among seven conventional maize (Zea mays) cultivars grown in six different locations in Germany during two consecutive seasons was evaluated. Besides maize genotype, both geographic location and season had a significant effect on protein profiles. Differences as high as 55- and 53-fold in the quantity of specific proteins were recorded, the median observed difference being around 6- and 5-fold between the genotypes and growing locations, respectively. Understanding the variation in the quantity of individual proteins should help to put the variation of endogenous proteins and the novel proteins in the genetically modified plants in perspective. This together with the targeted analyses the profiling methods, including proteomics, could also help to get a deeper insight into the unintended alterations that might have occurred during the genetic modification process. PMID:20968288

Anttonen, Mikko J; Lehesranta, Satu; Auriola, Seppo; Röhlig, Richard M; Engel, Karl-Heinz; Kärenlampi, Sirpa O

2010-12-01

88

The art and design of genetic screens: maize  

Microsoft Academic Search

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 in this organism, and emphasize the available tools. Screens exploit the well-studied behaviour of

Héctor Candela; Sarah Hake

2008-01-01

89

Random amplified polymorphic DNA analysis of genetically modified organisms.  

PubMed

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. PMID:16860900

Yoke-Kqueen, Cheah; Radu, Son

2006-12-15

90

SOIL ECOLOGICAL AND ECONOMIC EVALUATION OF GENETICALLY MODIFIED CROPS - ECOGEN Hierarchical classification of environmental factors and agricultural practices affecting soil fauna under cropping systems using Bt maize  

Microsoft Academic Search

Summary The population dynamics of soil organisms under agricultural field conditions are influenced by many factors, such as pedology and climate, but also farming practices such as crop type, tillage and the use of pesticides. To assess the real effects of farming practices on soil organisms it is necessary to rank the influence of all of these parameters. Bt maize

Marko Debeljaka; Paul H. Kroghd; Saso Dzeroskia; Batiment Villemin

91

A three-year longitudinal study on the effects of a diet containing genetically modified Bt176 maize on the health status and performance of sheep  

Microsoft Academic Search

This study shows that a diet including insect-resistant Bt176 maize, fed to 53 ewes and their progeny for 3 years, did not have adverse effects on their health or performance and that no horizontal gene transfer to ruminal microorganisms or animal tissues was detected. No differences were observed regarding performance, reproductive traits, haematological parameters, antioxidant defences, lymphocyte proliferative capacity, phagocytosis and

Massimo Trabalza-Marinucci; Giorgio Brandi; Cristina Rondini; Luca Avellini; Camilla Giammarini; Silva Costarelli; Gabriele Acuti; Chiara Orlandi; Giovanni Filippini; Elisabetta Chiaradia; Manuela Malatesta; Silvia Crotti; Chiara Antonini; Giulia Amagliani; Elisabetta Manuali; Anna Rita Mastrogiacomo; Livia Moscati; Mohamed Naceur Haouet; Alberto Gaiti; Mauro Magnani

2008-01-01

92

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

PubMed

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. PMID:20595789

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

2010-01-01

93

Genetically Modified Food: Bt Corn  

NSDL National Science Digital Library

This online article is from the Museum's Seminars on Science, a series of distance-learning courses designed to help educators meet the new national science standards. Genetically Modified Food: Bt Corn, part of the Genetics, Genomics, Genethics seminar, briefly covers the planting of genetically modified corn instead of using insecticides and the possible ill effects this corn may have on monarch butterflies.

94

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

PubMed

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. PMID:19105640

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

2009-01-28

95

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

PubMed

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 ?g 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. PMID:21604675

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

2011-07-13

96

Metabolite profiling of maize kernels--genetic modification versus environmental influence.  

PubMed

A metabolite profiling approach based on gas chromatography-mass spectrometry (GC-MS) was applied to investigate the metabolite profiles of genetically modified (GM) Bt-maize (DKC78-15B, TXP 138F) and Roundup Ready-maize (DKC78-35R). For the comparative investigation of the impact of genetic modification versus environmental influence on the metabolite profiles, GM maize was grown together with the non-GM near-isogenic comparators under different environmental conditions, including several growing locations and seasons in Germany and South Africa. Analyses of variance (ANOVA) revealed significant differences between GM and non-GM maize grown in Germany and South Africa. For the factor genotype, 4 and 3%, respectively, of the total number of peaks detected by GC-MS showed statistically significant differences (p < 0.01) in peak heights as compared to the respective isogenic lines. However, ANOVA for the factor environment (growing location, season) revealed higher numbers of significant differences (p < 0.01) between the GM and the non-GM maize grown in Germany (42%) and South Africa (10%), respectively. This indicates that the majority of differences observed are related to natural variability rather than to the genetic modifications. In addition, multivariate data assessment by means of principal component analysis revealed that environmental factors, that is, growing locations and seasons, were dominant parameters driving the variability of the maize metabolite profiles. PMID:22375597

Frank, Thomas; Röhlig, Richard M; Davies, Howard V; Barros, Eugenia; Engel, Karl-Heinz

2012-03-28

97

The genetic architecture of maize stalk strength.  

PubMed

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 4,692 recombinant inbreds (RILs) comprising the maize nested association mapping (NAM) panel derived from crosses of diverse inbreds to the inbred, B73. An intermated B73×Mo17 family (IBM) of 196 RILs and a panel of 2,453 diverse inbreds from the North Central Regional Plant Introduction Station (NCRPIS) were also evaluated. We measured RPR in three environments. Family-nested QTL were identified by joint-linkage mapping in the NAM panel. We also performed a genome-wide association study (GWAS) and genomic best linear unbiased prediction (GBLUP) in each panel. Broad sense heritability computed on a line means basis was low for RPR. Only 8 of 26 families had a heritability above 0.20. The NCRPIS diversity panel had a heritability of 0.54. Across NAM and IBM families, 18 family-nested QTL and 141 significant GWAS associations were identified for RPR. Numerous weak associations were also found in the NCRPIS diversity panel. However, few were linked to loci involved in phenylpropanoid and cellulose synthesis or vegetative phase transition. Using an identity-by-state (IBS) relationship matrix estimated from 1.6 million single nucleotide polymorphisms (SNPs) and RPR measures from 20% of the NAM panel, genomic prediction by GBLUP explained 64±2% of variation in the remaining RILs. In the NCRPIS diversity panel, an IBS matrix estimated from 681,257 SNPs and RPR measures from 20% of the panel explained 33±3% of variation in the remaining inbreds. These results indicate the high genetic complexity of stalk strength and the potential for genomic prediction to hasten its improvement. PMID:23840585

Peiffer, Jason A; Flint-Garcia, Sherry A; De Leon, Natalia; McMullen, Michael D; Kaeppler, Shawn M; Buckler, Edward S

2013-01-01

98

Intraspecific violation of genetic colinearity and its implications in maize  

PubMed Central

Although allelic sequences can vary extensively, it is generally assumed that each gene in one individual will have an allelic counterpart in another individual of the same species. We report here that this assumption does not hold true in maize. We have sequenced over 100 kb from the bz genomic region of two different maize lines and have found dramatic differences between them. First, the retrotransposon clusters, which comprise most of the repetitive DNA in maize, differ markedly in make-up and location relative to the genes in the bz region. Second, and more importantly, the genes themselves differ between the two lines, demonstrating that genetic microcolinearity can be violated within the same species. Our finding has bearing on the underlying genetic basis of hybrid vigor in maize, and possibly other organisms, and on the measurement of genetic distances.

Fu, Huihua; Dooner, Hugo K.

2002-01-01

99

Genetically modified myths and realities.  

PubMed

Myths abound when it comes to GE crops. At their worst, myths play an active role in discouraging the use of GE to solve problems that afflict humankind, such as malnutrition and birth defects. Of all the various myths, two have been particularly important in preventing the use of GE maize in its areas of origin. The first is that transgenic maize will contaminate and destroy land races, thus destroying biodiversity and its associated cultural traditions. This myth totally ignores the fact that the gene flow that has taken place between maize and its progenitor, between the land races, and between land races and modern hybrids, has not led to any dire consequences. The second myth is that crops are natural and have not been modified by humans, or if they have, that plant breeding does not alter DNA. This myth ignores the fact that for the most part, it is impossible to alter the appearance of crops without changing the DNA. In fact, DNA movement within the crop genome is normal and its movement leads to double-strand DNA repair, with results like those found around transgene insertion sites. In addition, plants have ways to create novel genes. These changes help plants adapt to evolution and to human selection. The net result is that changes similar to what happens during the production of engineered plants takes place anyway in plant genomes. PMID:20609417

Parrott, Wayne

2010-11-30

100

From Many, One: Genetic Control of Prolificacy during Maize Domestication  

PubMed Central

A reduction in number and an increase in size of inflorescences is a common aspect of plant domestication. When maize was domesticated from teosinte, the number and arrangement of ears changed dramatically. Teosinte has long lateral branches that bear multiple small ears at their nodes and tassels at their tips. Maize has much shorter lateral branches that are tipped by a single large ear with no additional ears at the branch nodes. To investigate the genetic basis of this difference in prolificacy (the number of ears on a plant), we performed a genome-wide QTL scan. A large effect QTL for prolificacy (prol1.1) was detected on the short arm of chromosome 1 in a location that has previously been shown to influence multiple domestication traits. We fine-mapped prol1.1 to a 2.7 kb “causative region” upstream of the grassy tillers1 (gt1) gene, which encodes a homeodomain leucine zipper transcription factor. Tissue in situ hybridizations reveal that the maize allele of prol1.1 is associated with up-regulation of gt1 expression in the nodal plexus. Given that maize does not initiate secondary ear buds, the expression of gt1 in the nodal plexus in maize may suppress their initiation. Population genetic analyses indicate positive selection on the maize allele of prol1.1, causing a partial sweep that fixed the maize allele throughout most of domesticated maize. This work shows how a subtle cis-regulatory change in tissue specific gene expression altered plant architecture in a way that improved the harvestability of maize.

Wills, David M.; Whipple, Clinton J.; Takuno, Shohei; Kursel, Lisa E.; Shannon, Laura M.; Ross-Ibarra, Jeffrey; Doebley, John F.

2013-01-01

101

Genetic Modifiers of Ovarian Cancer.  

National Technical Information Service (NTIS)

Individuals with germline mutations in BRCA1 have an elevated but incomplete risk of developing ovarian cancer suggesting the presence of genetic modifiers of ovarian cancer in this population. A genome wide association study (GWAS) for ovarian cancer in ...

F. J. Couch

2012-01-01

102

Prospects for reducing fumonisin contamination of maize through genetic modification.  

PubMed

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 defense systems in kernel tissues. This has not yet been accomplished in maize, although promising results have been obtained recently in other monocots versus other fungal and bacterial pathogens. Achieving reproducible and stable enhanced ear mold resistance under field conditions will be immensely challenging for biotechnologists. A third approach, transgene strategies aimed at preventing mycotoxin biosynthesis, or detoxifying mycotoxins in planta, could provide further protection for the grower in environments where FBs present a risk to the crop even when the maize is relatively resistant to Fusarium mold. In one example of such a strategy, enzymes that degrade FBs have been identified in a filamentous saprophytic fungus isolated from maize, and corresponding genes have been cloned and are currently being tested in transgenic maize. PMID:11359705

Duvick, J

2001-05-01

103

Prospects for reducing fumonisin contamination of maize through genetic modification.  

PubMed Central

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 defense systems in kernel tissues. This has not yet been accomplished in maize, although promising results have been obtained recently in other monocots versus other fungal and bacterial pathogens. Achieving reproducible and stable enhanced ear mold resistance under field conditions will be immensely challenging for biotechnologists. A third approach, transgene strategies aimed at preventing mycotoxin biosynthesis, or detoxifying mycotoxins in planta, could provide further protection for the grower in environments where FBs present a risk to the crop even when the maize is relatively resistant to Fusarium mold. In one example of such a strategy, enzymes that degrade FBs have been identified in a filamentous saprophytic fungus isolated from maize, and corresponding genes have been cloned and are currently being tested in transgenic maize.

Duvick, J

2001-01-01

104

Genetically modified probiotics in foods.  

PubMed

Probiotics have many potential therapeutic uses, but have not been universally accepted because of a lack of understanding of their action. Lactic acid bacteria (LAB) have been modified by traditional and genetic engineering methods to produce new varieties. Modern techniques of molecular biology have facilitated the identification of probiotic LAB strains, but only a few LAB have been modified by recombinant-DNA technology because of consumer resistance to their introduction to markets, especially in Europe. PMID:14573362

Ahmed, Farid E

2003-11-01

105

Integrating genetic linkage maps with pachytene chromosome structure in maize.  

PubMed Central

Genetic linkage maps reveal the order of markers based on the frequency of recombination between markers during meiosis. Because the rate of recombination varies along chromosomes, it has been difficult to relate linkage maps to chromosome structure. Here we use cytological maps of crossing over based on recombination nodules (RNs) to predict the physical position of genetic markers on each of the 10 chromosomes of maize. This is possible because (1). all 10 maize chromosomes can be individually identified from spreads of synaptonemal complexes, (2). each RN corresponds to one crossover, and (3). the frequency of RNs on defined chromosomal segments can be converted to centimorgan values. We tested our predictions for chromosome 9 using seven genetically mapped, single-copy markers that were independently mapped on pachytene chromosomes using in situ hybridization. The correlation between predicted and observed locations was very strong (r(2) = 0.996), indicating a virtual 1:1 correspondence. Thus, this new, high-resolution, cytogenetic map enables one to predict the chromosomal location of any genetically mapped marker in maize with a high degree of accuracy. This novel approach can be applied to other organisms as well.

Anderson, Lorinda K; Salameh, Naser; Bass, Hank W; Harper, Lisa C; Cande, W Z; Weber, Gerd; Stack, Stephen M

2004-01-01

106

Estimating maize genetic erosion in modernized smallholder agriculture  

Microsoft Academic Search

Replacement of crop landraces by modern varieties is thought to cause diversity loss. We studied genetic erosion in maize\\u000a within a model system; modernized smallholder agriculture in southern Mexico. The local seed supply was described through\\u000a interviews and in situ seed collection. In spite of the dominance of commercial seed, the informal seed system was found to\\u000a persist. True landraces

Joost van Heerwaarden; J. Hellin; R. G. F. Visser; F. A. van Eeuwijk

2009-01-01

107

Genetic and Physiological Analysis of Iron Biofortification in Maize Kernels  

PubMed Central

Background Maize is a major cereal crop widely consumed in developing countries, which have a high prevalence of iron (Fe) deficiency anemia. The major cause of Fe deficiency in these countries is inadequate intake of bioavailable Fe, where poverty is a major factor. Therefore, biofortification of maize by increasing Fe concentration and or bioavailability has great potential to alleviate this deficiency. Maize is also a model system for genomic research and thus allows the opportunity for gene discovery. Here we describe an integrated genetic and physiological analysis of Fe nutrition in maize kernels, to identify loci that influence grain Fe concentration and bioavailability. Methodology Quantitative trait locus (QTL) analysis was used to dissect grain Fe concentration (FeGC) and Fe bioavailability (FeGB) from the Intermated B73 × Mo17 (IBM) recombinant inbred (RI) population. FeGC was determined by ion coupled argon plasma emission spectroscopy (ICP). FeGB was determined by an in vitro digestion/Caco-2 cell line bioassay. Conclusions Three modest QTL for FeGC were detected, in spite of high heritability. This suggests that FeGC is controlled by many small QTL, which may make it a challenging trait to improve by marker assisted breeding. Ten QTL for FeGB were identified and explained 54% of the variance observed in samples from a single year/location. Three of the largest FeGB QTL were isolated in sister derived lines and their effect was observed in three subsequent seasons in New York. Single season evaluations were also made at six other sites around North America, suggesting the enhancement of FeGB was not specific to our farm site. FeGB was not correlated with FeGC or phytic acid, suggesting that novel regulators of Fe nutrition are responsible for the differences observed. Our results indicate that iron biofortification of maize grain is achievable using specialized phenotyping tools and conventional plant breeding techniques.

Szalma, Stephen J.; Hart, Jonathan J.; Rutzke, Michael A.; Kochian, Leon V.; Glahn, Raymond P.; Hoekenga, Owen A.

2011-01-01

108

Impact of the Maize Rhizosphere on the Genetic Structure, the Diversity and the Atrazine-degrading Gene Composition of Cultivable Atrazine-degrading Communities  

Microsoft Academic Search

Sixty-six atrazine-degrading bacterial communities utilizing atrazine as sole N source and citrate as principal C source were\\u000a isolated from unplanted and maize planted soils treated with atrazine. Ribosomal intergenic spacer analysis (RISA) fingerprints\\u000a revealed that the genetic structure of atrazine-degrading bacterial communities was modified in the maize rhizosphere. To\\u000a assess the underlying microbial diversity, 16S rDNA sequences amplified from each

Fabrice Martin-Laurent; Benoît Barrès; Isabelle Wagschal; Séverine Piutti; Marion Devers; Guy Soulas; Laurent Philippot

2006-01-01

109

Catalan agriculture and genetically modified organisms (GMOs) — An application of DPSIR model  

Microsoft Academic Search

Although there is a strong controversy regarding the introduction and commercialisation of genetically modified organisms (GMOs) in Europe, GM maize has been sown in Spain since 1998. Stakeholders' positions on the role that GMOs play in trends of the state of agriculture and environment in Catalonia are analysed. The application of the Driving forces –Pressures – State – Impact –

Rosa Binimelis; Iliana Monterroso; Beatriz Rodríguez-Labajos

2009-01-01

110

Multiplex polymerase chain reaction and ligation detection reaction\\/universal array technology for the traceability of genetically modified organisms in foods  

Microsoft Academic Search

A multiplex polymerase chain reaction (PCR) system was developed for the simultaneous detection of target sequences in genetically modified soybean (Roundup Ready) and maize (MON810, Bt176, Bt11, and GA21). Primer pairs were designed to amplify the junction regions of the transgenic constructs analyzed and the endogenous genes of soybean (lectin) and maize (zein) were included as internal control targets to

C. Peano; R. Bordoni; M. Gulli; A. Mezzelani; M. C. Samson; G. De Bellis; N. Marmiroli

2005-01-01

111

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

ERIC Educational Resources Information Center

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)

Brandner, Diana L.

2002-01-01

112

[Genetic improvement of breeding materials in tropical and sub- tropical maize].  

PubMed

In the present study, 122 maize local cultivars and adapted exotic germplasm from Thailand were used to develop open pollinate varieties (OPVs) using modified ear-to-row scheme, top-cross or test-cross programmes. Ten new maize OPVs with distinct characters were created based on the precise breeding objectives and directional design. The selection of breeding materials was based upon three factors: elite performance, broad adaptability, and genetic diversity. The synthesizing system provided four features: genetic mixing and recombination, equal comparable genetic contribution, mild selection pressure, and maximum intermating for genetic equilibrium (i.e., the female traits were close for the genetic com-positions). Subsequently, Suwan 1 composite and its deritives (Suwan 2, Suwan 3 composite, Suwan 5 and KS24 synthetics), KS6 and KS28 synthetics with the dent type of different origins, and Caripeno DMR composite, KS23, and KS27 synthetics with the dent type of Non-Suwan 1 origin were developed. These OPVs had been improved for 2~13 cycles using S1 recurrent selection method. About 50 inbred lines were developed from these OPVs, and 16 elite single (three-way) crosses were combined and released from these inbred lines. At present, at least one parental inbred line of all the tropical hybrids was derived from Suwan (KS) germplasm in Thailand. Based on the theory of the synthesizing OPVs and developing inbred lines, this paper discussed the genetic moderate diversity, relationship, heterotic group, and patterns for synthesizing OPVs, and inspiration for composed OPVs to heterosis breeding. PMID:22207385

Sansern, Jampatong; Chaba, Jampatong

2011-12-01

113

Gene transfer from genetically modified food.  

PubMed

The current debate about the safety of genetically modified food includes some important scientific issues where more scientific data would aid the robustness of safety evaluation. One example is the possibility of gene transfer, especially from genetically modified plant material. PMID:11024371

Gasson, M J

2000-10-01

114

P OPULATION STRUCTURE AND GENETIC DIVERSITY OF NEW WORLD MAIZE RACES ASSESSED BY DNA MICROSATELLITES 1  

Microsoft Academic Search

Because of the economic importance of maize and its scientifi c importance as a model system for studies of domestication, its evolutionary history is of general interest. We analyzed the population genetic structure of maize races by genotyping 964 indi- vidual plants, representing almost the entire set of ~350 races native to the Americas, with 96 microsatellites. Using Bayesian clustering,

Yves Vigouroux; Jeffrey C. Glaubitz; Yoshihiro Matsuoka; Major M. Goodman; John Doebley

2008-01-01

115

Evaluating the nutritional impact of maize varieties genetically improved for protein quality  

Microsoft Academic Search

Biofortification, or the genetic improvement of the nutritional quality of food crops, is a promising technology to combat childhood undernutrition in developing countries. Significant progress has been made to develop maize varieties with improved protein quality, collectively known as quality protein maize (QPM). However, debate still continues over whether this agricultural technology will have a significant public health impact. A

Nilupa S Gunaratna

2007-01-01

116

Genetic Analysis of the Morphological Differences between Maize and Teosinte  

PubMed Central

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.

Doebley, J.; Stec, A.

1991-01-01

117

Genetically Modified Animals and Pharmacological Research  

Microsoft Academic Search

\\u000a This chapter reviews the use of genetically modified animals and the increasingly detailed knowledge of the genomes of the\\u000a domestic species. The different approaches to genetic modification are outlined as are the advantages and disadvantages of\\u000a the techniques in different species. Genetically modified mice have been fundamental in understanding gene function and in\\u000a generating affordable models of human disease although

Dominic J. Wells

118

Validation of a method based on polymerase chain reaction for the detection of genetically modified organisms in various processed foodstuffs  

Microsoft Academic Search

A qualitative screening method was validated for the detection of genetically modified organisms (GMOs) in various processed food matrices (cooked maize grit, infant formula, biscuits, meal of acidified soybeans). The prepared food matrices contained each 0%, 2%, 100% (10% instead of 100% in the case of biscuits) of Roundup-Ready© soybeans and\\/or of Bt-176 maize. The method was based on the

Markus Lipp; Anke Bluth; Fabrice Eyquem; Lothar Kruse; Heinz Schimmel; G. Van den Eede; E. Anklam

2001-01-01

119

Genetic dissection of maize phenology using an intraspecific introgression library  

PubMed Central

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 between the two parental genotypes, this collection will serve as a permanent source of nearly isogenic materials for multiple studies of QTL analysis and cloning.

2011-01-01

120

Genetic analysis of vertical root pulling resistance (VRPR) in maize using two genetic populations  

Microsoft Academic Search

Root traits are important in improving nutrient and water use efficiency. Vertical root pulling resistance (VRPR) has been\\u000a shown to be closely related to root system characteristics in maize (Zea mays L.). In the present study, two genetic populations derived from the same parents, one containing 218 recombinant inbred lines\\u000a (RILs) and the other containing 187 advanced backcross BC4F3 lines,

Jianchao LiuHongguang; Hongguang Cai; Qun Chu; Xiaohui Chen; Fanjun Chen; Lixing Yuan; Guohua Mi; Fusuo Zhang

121

Detection of genetic integrity of conserved maize ( Zea mays L.) germplasm in genebanks using SNP markers  

Microsoft Academic Search

Twenty maize landrace accessions regenerated and conserved in five maize genebanks were investigated for genetic integrity\\u000a using 1,150 Single Nucleotide Polymorphisms (SNPs) and 235 SNP haplotypes. The genetic diversity of three accessions changed\\u000a significantly in terms of the average number of alleles per locus. Ten out of twenty accessions had significantly different\\u000a SNP allelic frequencies, either after regeneration or in

Weiwei Wen; Suketoshi Taba; Trushar Shah; Victor H. Chavez Tovar; Jianbing Yan

2011-01-01

122

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

PubMed

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. PMID:24195276

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

2013-01-01

123

GENETICALLY MODIFIED MICE IN NEUROPHARMACOLOGY  

Microsoft Academic Search

Since the first transgenic mouse was reported in 1980, genetically engineered mice have become an invaluable biological tool for better understanding of physiological and pathological processes in many fields of biomedical research. The transgenic technology allows researchers to carry out specific genetic manipulation in all cells of a laboratory animal, and makes it possible to dissect gene function in a

ROSSELLA BRUSA

1999-01-01

124

Out of America: tracing the genetic footprints of the global diffusion of maize.  

PubMed

Maize was first domesticated in a restricted valley in south-central Mexico. It was diffused throughout the Americas over thousands of years, and following the discovery of the New World by Columbus, was introduced into Europe. Trade and colonization introduced it further into all parts of the world to which it could adapt. Repeated introductions, local selection and adaptation, a highly diverse gene pool and outcrossing nature, and global trade in maize led to difficulty understanding exactly where the diversity of many of the local maize landraces originated. This is particularly true in Africa and Asia, where historical accounts are scarce or contradictory. Knowledge of post-domestication movements of maize around the world would assist in germplasm conservation and plant breeding efforts. To this end, we used SSR markers to genotype multiple individuals from hundreds of representative landraces from around the world. Applying a multidisciplinary approach combining genetic, linguistic, and historical data, we reconstructed possible patterns of maize diffusion throughout the world from American "contribution" centers, which we propose reflect the origins of maize worldwide. These results shed new light on introductions of maize into Africa and Asia. By providing a first globally comprehensive genetic characterization of landraces using markers appropriate to this evolutionary time frame, we explore the post-domestication evolutionary history of maize and highlight original diversity sources that may be tapped for plant improvement in different regions of the world. PMID:23921956

Mir, C; Zerjal, T; Combes, V; Dumas, F; Madur, D; Bedoya, C; Dreisigacker, S; Franco, J; Grudloyma, P; Hao, P X; Hearne, S; Jampatong, C; Laloë, D; Muthamia, Z; Nguyen, T; Prasanna, B M; Taba, S; Xie, C X; Yunus, M; Zhang, S; Warburton, M L; Charcosset, A

2013-11-01

125

Evidence for multilocus genetic control of preferential fertilisation in maize.  

PubMed

Genetic segregation was studied in more than 1900 seedlings of an F2 between the maize (Zea mays L.) inbred lines T232 and CM37. Significant segregation distortion was observed at 11 of 17 segregating allozyme loci and at a single morphological marker locus distributed on 7 of the 10 chromosomes in the genome. Deviations from genotypic class expectations were small for most loci, and averaged 7.7 per cent. Percent transmission of the allele contributed by T232 varied from 47.7 per cent to 53.3 per cent. The allele donated by T232 was significantly under-represented for loci on chromosomes 1 and 8, whereas the allele contributed by CM37 was deficient for nine of the ten segregating loci on chromosomes 2, 3, and 6. In all cases, the parental origin of the deficient allele was consistent for markers on a chromosome. Evidence is presented that suggests the aberrant ratios arose from linkage of the markers with genetic factors affecting prezygotic transmission, and that a minimum of 5 such factors were operative, one on each of chromosomes 1, 2, 3, 6, and 8. In contrast to the multi-locus and multi-chromosomal distorted segregation observed in the F2, all loci in backcross progenies fit Mendelian expectations. It is suggested that this discrepancy reflects variable environmental selection pressures on genes that influence aspects of gamete competition. PMID:3471740

Wendel, J F; Edwards, M D; Stuber, C W

1987-04-01

126

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

PubMed Central

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.

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

2003-01-01

127

Tropical maize germplasm: what can we say about its genetic diversity in the light of molecular markers?  

Microsoft Academic Search

Knowledge about genetic variability of a crop allows for more efficient and effective use of resources in plant improvement\\u000a programs. The genetic variation within temperate maize has been studied extensively, but the levels and patterns of diversity\\u000a in tropical maize are still not well understood. Brazilian maize germplasm represents a very important pool of genetic diversity\\u000a due to many past

P. R. Laborda; K. M. Oliveira; A. A. F. Garcia; M. E. A. G. Z. Paterniani; A. P. de Souza

2005-01-01

128

Testing for Genetically Modified Foods Using PCR  

ERIC Educational Resources Information Center

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…

Taylor, Ann; Sajan, Samin

2005-01-01

129

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

PubMed Central

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.

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

130

Splicing regulation as a potential genetic modifier  

Microsoft Academic Search

Inherited diseases are associated with profound phenotypic variability, which is affected strongly by genetic modifiers. The splicing machinery could be one such modifying system, through a mechanism involving splicing motifs and their interaction with a complex repertoire of splicing factors. Mutations in splicing motifs and changes in levels of splicing factors can result in different splicing patterns. Changes in the

Malka Nissim-Rafinia; Batsheva Kerem

2002-01-01

131

Maize Authentication: Quality Control Methods and Multivariate Analysis (Chemometrics)  

Microsoft Academic Search

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

Ioannis S. Arvanitoyannis; Antonios Vlachos

2009-01-01

132

Genetically modified mice and cognition  

Microsoft Academic Search

Cognition in transgenic and knockout mice is preferentially assessed by spatial learning in the Morris water maze. Awareness is growing, however, that the putative cognitive deficits observed using such a paradigm may be biased by the genetic background and behavioral peculiarities of the specific animals used. Recent progress in cognitive research includes new behavioral tests and refined analysis of performance

Hans-Peter Lipp; David P Wolfer

1998-01-01

133

[Genetically modified food--unnecessary controversy?].  

PubMed

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. PMID:23243917

Tchórz, Micha?; Radoniewicz-Chagowska, Anna; Lewandowska-Stanek, Hanna; Szponar, Elzbieta; Szponar, Jaros?aw

2012-01-01

134

Effects of genetics and environment on the metabolome of commercial maize hybrids: a multisite study.  

PubMed

This study was designed to elucidate the biological variation in expression of many metabolites due to environment, genotype, or both, and to investigate the potential utility of metabolomics to supplement compositional analysis for substantial equivalence assessments of genetically modified (GM) crops. A total of 654 grain and 695 forage samples from 50 genetically diverse non-GM DuPont Pioneer maize hybrids grown at six locations in the U.S. and Canada were analyzed by coupled gas chromatography time-of-flight-mass spectrometry (GC/TOF-MS). A total of 156 and 185 metabolites were measured in grain and forage samples, respectively. Univariate and multivariate statistical analyses were employed extensively to compare and correlate the metabolite profiles. We show that the environment had far more impact on the forage metabolome compared to the grain metabolome, and the environment affected up to 50% of the metabolites compared to less than 2% by the genetic background. The findings from this study demonstrate that the combination of GC/TOF-MS metabolomics and comprehensive multivariate statistical analysis is a powerful approach to identify the sources of natural variation contributed by the environment and genotype. PMID:23113862

Asiago, Vincent M; Hazebroek, Jan; Harp, Teresa; Zhong, Cathy

2012-11-21

135

Genetic diversity of maize germplasm assessed by retrotransposon-based markers.  

PubMed

Maize is one of the most important crops and also a model for grass genome research. Transposable elements comprise over 78% of the maize genome and their ability to generate new copies makes them good potential markers. Interretrotransposon-amplified polymorphism (IRAP) and retrotransposon microsatellite amplified polymorphism (REMAP) protocols were used for the first time in maize to study the genetic variability between maize cultivars. Ten PCR primers were selected based on a systematic analysis of the sequence conservation in the extremities of different high copy number transposable elements, whereas one primer was chosen based on a microsatellite sequence. Of the 16 primer combinations tested, 14 produced polymorphic bands. These markers were used to identify genetic similarity among 20 maize cultivars selected by their different kernel oil content. Genetic similarity analysis was performed based on the polymorphic band profiles and dendrograms were developed by the unweighted pair-group method with arithmetic averages. Clustering technique revealed that samples were grouped into three clusters that differed in their kernel oil content and size, and in their relative embryo size. In the current investigation, there is evidence that IRAP/REMAP may be useful as markers in maize. PMID:24634146

Kuhn, Betty Cristiane; López-Ribera, Ignacio; da Silva Machado, Maria de Fátima Pires; Vicient, Carlos M

2014-07-01

136

Genetically modified sugarcane for bioenergy generation.  

PubMed

Sugarcane breeding has significantly progressed over the past 30 years, but attempts to further increase crop yield have been limited due to the complexity of the sugarcane genome. An alternative to boost the crop yield is the introduction of genes encoding desirable traits in the elite sugarcane cultivars. Genetically modified sugarcane with increased yield and pest and disease resistance has already proven its value not only by the increased sugar content but also for the improvement of the crop performance. However, transgene stability is still a challenge since transgene silencing seems to occur in a large proportion of genetically modified sugarcane plants. In addition, regulatory issues associated with the crop propagation model will also be a challenge to the commercial approval of genetically modified sugarcane. PMID:22093808

Arruda, Paulo

2012-06-01

137

Genetically modified mice and cognition.  

PubMed

Cognition in transgenic and knockout mice is preferentially assessed by spatial learning in the Morris water maze. Awareness is growing, however, that the putative cognitive deficits observed using such a paradigm may be biased by the genetic background and behavioral peculiarities of the specific animals used. Recent progress in cognitive research includes new behavioral tests and refined analysis of performance impairments. Advances in our understanding of memory and learning are being made possible through use of transgenic rescue of disrupted genes, inducible and reversible gene targeting in selected brain regions, and single-cell recordings of hippocampal place cells in mutant mice. PMID:9635213

Lipp, H P; Wolfer, D P

1998-04-01

138

Genetically modified animals and pharmacological research.  

PubMed

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. PMID:20204589

Wells, Dominic J

2010-01-01

139

Frankenfoods? The Debate Over Genetically Modified Crops  

NSDL National Science Digital Library

This discussion case, in which a university research laboratory is vandalized by environmental activists opposed to genetic engineering, focuses on the science and ethics of genetically modified crops. Students consider both the risks and benefits of biotechnology and explore the positions of various stakeholders, including environmentalists, conservationists, agricultural businesses, research scientists, and farmers. Originally written for a vegetable crops course, the case would be appropriate for a wide variety of courses in which biotechnology is discussed.

Rhodes, Bill; Alkhazindar, Maha M.; Schiller, Nancy A.

2001-01-01

140

Detection of genetically modified organisms in foods  

Microsoft Academic Search

Legislation enacted worldwide to regulate the presence of genetically modified organisms (GMOs) in crops, foods and ingredients, necessitated the development of reliable and sensitive methods for GMO detection. In this article, protein- and DNA-based methods employing western blots, enzyme-linked immunosorbant assay, lateral flow strips, Southern blots, qualitative-, quantitative-, real-time- and limiting dilution-PCR methods, are discussed. Where information on modified gene

Farid E. Ahmed

2002-01-01

141

[Effect of genetically modified plants on the development of rat progeny].  

PubMed

The paper presents the results of evaluating the effect of genetically modified (GM) maize on the prenatal and postnatal development of rat progeny in three generations. An experiment used 280 adult rats (160 females and 120 males) and 1545 infant rats of the first month of life. The animals were divided into 2 groups: 1) those given a diet including GM maize (an experimental group); 2) those fed on its isogenic control (a control group). The maize was included into the diet in maximally possible amount that did not impair the balance of essential nutrients (31.4% caloric value). Analysis of the data obtained from studies of the prenatal (preimplantation and postimplantation death and fetal somatometric parameters) and postnatal (physical development, survival, changes in somatometric parameters) development of rat offspring revealed no effect of GM maize as compared to the isogenic control. All the parameters were in the normal physiological range typical of the animals of this species and age. Thus, dietary intake of the given amount of GM maize had no impact on rat progeny development. PMID:22250399

Tyshko, N V; Zhminchenko, V M; Pashorina, V A; Saprykin, V P; Seliaskin, K E; Utembaeva, N T; Tutel'ian, V A

2011-01-01

142

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

PubMed

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. PMID:20438128

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

2010-05-26

143

Genetic Control and Linkage Relationships among Aminopeptidases in Maize  

PubMed Central

Maize aminopeptidase is coded by four genes. Amp1 and Amp2 have been localized to chromosome 1. A three-point cross shows the gene order to be Amp2—15%—Amp1—33%—Adh2 (alcohol dehydrogenase). Amp3 and Amp4 assort independently of each other and of chromosome 1 aminopeptidases. Another linkage relationship among the maize genes Amy2 (amylase), Cat1 (catalase), and Amp3 exists, but the chromosome location has yet to be established unequivocally.

Ott, Lila; Scandalios, John G.

1978-01-01

144

Genetically modified plants – the debate continues  

Microsoft Academic Search

The debate about the potential risks and benefits of genetically modified organisms (GMOs) has hit the headlines over the past few months. The polarization of much of the debate obscures what really constitutes ecological risk, and what methods we can apply to identify and quantify those risks. Ecological science has much to offer in this respect, including ecological theory, manipulative

Rosie S. Hails

2000-01-01

145

Incentive Design for Introducing Genetically Modified Crops  

Microsoft Academic Search

The introduction of genetically modified (GM) crops raises several issues. This paper looks at incentives required to reduce problems of illegal and improper use of GM proprietary technology used in growing GM crops. A simple model of producer behaviour describes some key influences of a farmer’s response to GM crops. The model is illustrated using the example of INGARD? cotton

Ross S. Kingwell

2000-01-01

146

What makes genetically modified organisms so distasteful?  

Microsoft Academic Search

The debate concerning genetically modified organisms goes on unabated and reflects some genuine concerns. I suggest that a significantly large number of educated people believe that moving genes around between species is intuitively wrong and that this is based on an essentialist view of the world. This essentialist view has a long history that dates back to Plato and Aristotle

Keith G. Davies

2001-01-01

147

Trade Conflict Over Genetically Modified Organisms  

Microsoft Academic Search

In 2003 the USA, seconded by Argentina and Canada, initiated litigation in the World Trade Organization (WTO) against the European Union's regulatory policy for genetically modified organisms (GMOs). The three plaintiffs claimed that the EU's GMO policy was creating illegal trade restrictions. Specifically, they argued (i) that the EU had implemented a de facto moratorium on approval of new biotech

Thomas Bernauer; Philipp Aerni; Kevin Gallagher

148

Release of genetically modified organisms: precautionary legislation  

Microsoft Academic Search

This paper analyses the debates surrounding the drafting and passage through the UK Parliament of the Environmental Protection Bill, Part VI, regarding the potential hazards arising from release of genetically modified organisms (GMOs). Both the previous voluntary and the current statutory systems have been precautionary (or proactive) in their approach to risk regulation.The EPA establishes a framework for guiding decisions

Les Levidow; Joyce Tait

1992-01-01

149

Screening Methodologies for Genetic Modified Organsims (GMOs)  

Microsoft Academic Search

There is an increasing need for analytical methods for the detection of genetically modified organisms (GMOs) detection in food due to the growth of use of GMOs, or their derivatives, in the food industry. This paper aims to briefly introduce the reader to GMOs, to describe the state of the art in detection methods for GMOs, and to provide the

M. Minunni; M. Mascini; I. Cozzani

2000-01-01

150

Genetically Modified (GM) Foods: A Brief Perspective  

Microsoft Academic Search

Due to ever-increasing population burden, genetically modified (GM) foods promised great potential, to solve many of the world's hunger and malnutrition problems, and also to preserve the environment. The authentic GM foods may not only have better nutritional and pharmaceutical values but are also resistant to pest and diseases, tolerant to extreme temperatures and herbicides. Yet they pose many challenges

Farrukh Jamal; Q. S. Haque; Tabish Qidwai; U. P. India

151

Towards a Better Understanding of the Genetic and Physiological Basis for Nitrogen Use Efficiency in Maize  

PubMed Central

To enhance our understanding of the genetic basis of nitrogen use efficiency in maize (Zea mays), we have developed a quantitative genetic approach by associating metabolic functions and agronomic traits to DNA markers. In this study, leaves of vegetative recombinant inbred lines of maize, already assessed for their agronomic performance, were analyzed for physiological traits such as nitrate content, nitrate reductase (NR), and glutamine synthetase (GS) activities. A significant genotypic variation was found for these traits and a positive correlation was observed between nitrate content, GS activity and yield, and its components. NR activity, on the other hand, was negatively correlated. These results suggest that increased productivity in maize genotypes was due to their ability to accumulate nitrate in their leaves during vegetative growth and to efficiently remobilize this stored nitrogen during grain filling. Quantitative trait loci (QTL) for various agronomic and physiological traits were searched for and located on the genetic map of maize. Coincidences of QTL for yield and its components with genes encoding cytosolic GS and the corresponding enzyme activity were detected. In particular, it appears that the GS locus on chromosome 5 is a good candidate gene that can, at least partially, explain variations in yield or kernel weight. Because at this locus coincidences of QTLs for grain yield, GS, NR activity, and nitrate content were also observed, we hypothesize that leaf nitrate accumulation and the reactions catalyzed by NR and GS are coregulated and represent key elements controlling nitrogen use efficiency in maize.

Hirel, Bertrand; Bertin, Pascal; Quillere, Isabelle; Bourdoncle, William; Attagnant, Celine; Dellay, Christophe; Gouy, Aurelia; Cadiou, Sandrine; Retailliau, Catherine; Falque, Mathieu; Gallais, Andre

2001-01-01

152

The physical and genetic framework of the maize B73 genome.  

PubMed

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). PMID:19936061

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

153

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

PubMed

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 toxins and antinutrients on nutritional safety, also coherent databases of standard parental lines and clear criteria for mandatory declarations are necessary. PMID:10828499

Novak, W K; Haslberger, A G

2000-06-01

154

Maize tassel-modified carbon paste electrode for voltammetric determination of Cu(II).  

PubMed

The preparation and application of a practical electrochemical sensor for environmental monitoring and assessment of heavy metal ions in samples is a subject of considerable interest. In this paper, a carbon paste electrode modified with maize tassel for the determination of Cu(II) has been proposed. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) were used to study morphology and identify the functional groups on the modified electrode, respectively. First, Cu(II) was adsorbed on the carbon paste electrode surface at open circuit and voltammetric techniques were used to investigate the electrochemical performances of the sensor. The electrochemical sensor showed an excellent electrocatalytic activity towards Cu(II) at pH 5.0 and by increasing the amount of maize tassel biomass, a maximum response at 1:2.5 (maize tassel:carbon paste; w/w) was obtained. The electrocatalytic redox current of Cu(II) showed a linear response in the range (1.23 ?M to 0.4 mM) with the correlation coefficient of 0.9980. The limit of detection and current-concentration sensitivity were calculated to be 0.13 (±0.01) ?M and 0.012 (±0.001) ?A/?M, respectively. The sensor gave good recovery of Cu(II) in the range from 96.0 to 98.0 % when applied to water samples. PMID:24705875

Moyo, Mambo; Okonkwo, Jonathan O; Agyei, Nana M

2014-08-01

155

[Genetically modified food--great unknown].  

PubMed

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. PMID:23009001

Cichosz, G; Wiackowski, S K

2012-08-01

156

Genetically modified pigs to model human diseases.  

PubMed

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. PMID:24234401

Flisikowska, Tatiana; Kind, Alexander; Schnieke, Angelika

2014-02-01

157

Are genetically modified plants useful and safe?  

PubMed

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. PMID:16036615

Weil, Jacques-Henry

2005-01-01

158

Mailing of Genetically Modified Microorganisms: A Field Survey.  

National Technical Information Service (NTIS)

Research institutions exchange genetically modified bacterial strains by mail on a regular basis. Therefore, most countries have introduced strict rules which regulate the way in which genetically modified microorganisms are mailed. Also the IATA has form...

H. C. J. C. Cremers H. F. Groot

1991-01-01

159

Genetics of osmotic adjustment in breeding maize for drought tolerance1  

Microsoft Academic Search

Osmotic adjustment in higher plants refers to the maintenance of turgor by lowering of osmotic potential arising from the net accumulation of solutes in response to water deficits. Genetic variation for osmotic adjustment has been reported in several crops, but little is known about its inheritance and potential use as selection criteria in tropical maize (Zea mays L.). Two tropical

Robert G Guei; C E Wassom

1993-01-01

160

Genetic Analysis of the Morphological Differences Between Maize and Teosinte  

Microsoft Academic Search

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

John Doebley; Adrian Stec

1991-01-01

161

Genetically Modified Organisms as Invasive Species?  

Microsoft Academic Search

The release of genetically modified organisms (GMOs) is a controversial subject. Some perceive it to be the single most important\\u000a development in biology since the discovery of natural selection. Others are concerned that the movement of genes with no reference\\u000a to natural species boundaries could pose new ecological risks. One conjectural risk is that transgenes will either cause the\\u000a host

Rosie Hails; Tracey Timms-Wilson

162

Consumer acceptance of genetically modified potaoes  

Microsoft Academic Search

Slow consumer acceptance has inhibited the market for genetically modified (GM) potato products. Logistic growth functions\\u000a were used to model market development patterns for three comparable products — diet sodas, frozen potatoes and microwave ovens.\\u000a Predictions of GMpotato acceptance were based on averages for the comparable products. The model predicts that consumer acceptance\\u000a will be in the introduction stage of

Joseph F. Guenthner

2002-01-01

163

Identity Preservation Systems for Genetically Modified Potatoes  

Microsoft Academic Search

In spite of benefits to growers, processors, consumers and the environment, genetically modified (GM) potatoes were a market\\u000a failure in North America. Contributing to the failure was the lack of an identity preservation (IP) system that could have\\u000a prevented unapproved GM potato products from entering export markets. We interviewed 26 industry experts to identify recommended\\u000a practices for GM potato IP

Elliot A. Toevs; Joseph F. Guenthner; Aaron J. Johnson; Christopher S. McIntosh; Michael K. Thornton

164

Genetic basis of heterosis explored by simple sequence repeat markers in a random-mated maize population  

Microsoft Academic Search

The genetic basis of heterosis in crop plants has not been completely resolved. Our objective in this study was to determine the level of dominance for quantitative trait loci (QTLs) that underlie heterosis in maize ( Zea mays L.). An F 2 population of an elite maize single cross, LH200 × LH216, was random mated for three generations in an

H. Lu; J. Romero-Severson; R. Bernardo

2003-01-01

165

Engineering a thermoregulated intein-modified xylanase into maize for consolidated lignocellulosic biomass processing.  

PubMed

Plant cellulosic biomass is an abundant, low-cost feedstock for producing biofuels and chemicals. Expressing cell wall-degrading (CWD) enzymes (e.g. xylanases) in plant feedstocks could reduce the amount of enzymes required for feedstock pretreatment and hydrolysis during bioprocessing to release soluble sugars. However, in planta expression of xylanases can reduce biomass yield and plant fertility. To overcome this problem, we engineered a thermostable xylanase (XynB) with a thermostable self-splicing bacterial intein to control the xylanase activity. Intein-modified XynB (iXynB) variants were selected that have <10% wild-type enzymatic activity but recover >60% enzymatic activity upon intein self-splicing at temperatures >59 °C. Greenhouse-grown xynB maize expressing XynB has shriveled seeds and low fertility, but ixynB maize had normal seeds and fertility. Processing dried ixynB maize stover by temperature-regulated xylanase activation and hydrolysis in a cocktail of commercial CWD enzymes produced >90% theoretical glucose and >63% theoretical xylose yields. PMID:23086202

Shen, Binzhang; Sun, Xueguang; Zuo, Xiao; Shilling, Taran; Apgar, James; Ross, Mary; Bougri, Oleg; Samoylov, Vladimir; Parker, Matthew; Hancock, Elaina; Lucero, Hector; Gray, Benjamin; Ekborg, Nathan A; Zhang, Dongcheng; Johnson, Jeremy C Schley; Lazar, Gabor; Raab, R Michael

2012-11-01

166

DETECCIÓN DE PRODUCTOS DE MAIZ GENETICAMENTE MODIFICADOS POR LA REACCIÓN EN CADENA DE LA POLIMERASA  

Microsoft Academic Search

A polymerase chain reaction (PCR) was applied to detect genetically modified (GM) maize and soybean food product, using specific 35S promoter primers for inserted chimerical genes in maize or soybean. The PCR detected food products that include ingredients obtained from GMOs in maize grains and flour, as well as processed in foods such as tortillas (Mexican crepe), corn chips, corn

A. Mendoza; S. Fernández; M. A. Cruz; M. A. Rodríguez-Perez; Barrera Saldaña; Elias Piña

2006-01-01

167

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

SciTech Connect

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.

Pauly, Markus [UC Berkeley; Hake, Sarah [USDA Albany

2013-10-31

168

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

PubMed Central

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.

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

169

Unpacking atitudes towards genetically modified food.  

PubMed

The present study investigates the structure of attitudes towards genetically modified (GM) food. A total of 431 respondents completed a questionnaire measuring their overall attitude, cognition and affect towards GM food. A model with distinct positive and negative, affective and cognitive components and a separate factor for perceived risk and worry best accounted for the data. Negative--but not positive--components directly affected behavioural intentions. Implications of these findings for our understanding of attitudes towards GM food and their impact on behaviour are discussed. PMID:16154663

de Liver, Yaël; van der Pligt, Joop; Wigboldus, Daniël

2005-12-01

170

Genetically modified T cells to target glioblastoma.  

PubMed

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

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

2013-01-01

171

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

PubMed

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. PMID:22642164

Sorokina, E Iu; Chernyshova, O N

2012-01-01

172

A somatic gene rearrangement contributing to genetic diversity in maize.  

PubMed

We have discovered a somatic genomic rearrangement that occurs at high frequency at a duplicated zein locus in certain cultures of the maize inbred line A188. The rearranged allele arises from the duplication by a two-step process involving a homologous recombination and a second event, which may be a deletion, inversion, or insertion; both steps always occur together. The frequency of rearrangement is lower in homozygous states of the parental allele than in heterozygotes. In both cases, the rearrangement is shown to be mitotic. The rearranged product can be transmitted through meiosis, providing another mechanism for genome evolution in higher eukaryotes. PMID:2235998

Das, O P; Levi-Minzi, S; Koury, M; Benner, M; Messing, J

1990-10-01

173

DNA stability in plant tissues: implications for the possible transfer of genes from genetically modified food.  

PubMed

The potential for transfer of antibiotic resistance genes from genetically modified (GM) plant material to microbes through genetic recombination in the human or animal gut is a consideration that has engendered caution in the use of GM foods. This study was aimed at defining the optimal physical and chemical conditions necessary to ensure sufficient fragmentation of DNA in plant tissues to a size where it would be unlikely to be stably transferred to bacterial gut microflora. The ribulose 1,5-bisphosphate carboxylase/oxygenase small subunit (Rubisco SS) genes are of similar size (approximately 1.4 kb) to transgenes present in GM plants. DNA analysis and PCR amplification of Rubisco SS genes showed that fresh maize and maize silage contained high molecular weight DNA and intact Rubisco SS genes. Relatively high temperatures and pressurised steam were necessary to degrade fully genomic DNA and Rubisco SS genes in maize and wheat grains, the source of most animal feedstuffs. Furthermore, chemical expulsion and extrusion of oilseeds resulted in residues with completely degraded genomic DNA. These results imply that stringent conditions are needed in the processing of GM plant tissues for feedstuffs to eliminate the possibility of transmission of transgenes. PMID:10996317

Chiter, A; Forbes, J M; Blair, G E

2000-09-15

174

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

PubMed

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. PMID:23205714

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

2013-02-01

175

Genetic and Morphological Analysis of a Maize-Teosinte F_2 Population: Implications for the Origin of Maize  

Microsoft Academic Search

Genes controlling the dramatic morphological differences between maize and its presumed progenitor (teosinte) were investigated in a maize-teosinte F_2 population through the use of molecular markers. Results indicate that the key traits differentiating maize and teosinte are each under multigenic control, although for some traits, such as the number of ranks of cupules, the data are consistent with a mode

John Doebley; Adrian Stec; Jonathan Wendel; Marlin Edwards

1990-01-01

176

Genetic Analysis of 63 Mutations Affecting Maize Kernel Development Isolated from Mutator Stocks  

PubMed Central

Sixty-three mutations affecting development of the maize kernel were isolated from active Robertson's Mutator (Mu) stocks. At least 14 previously undescribed maize gene loci were defined by mutations in this collection. Genetic mapping located 53 of these defective kernel (dek) mutations to particular chromosome arms, and more precise map determinations were made for 21 of the mutations. Genetic analyses identified 20 instances of allelism between one of the novel mutations and a previously described dek mutation, or between new dek mutations identified in this study; phenotypic variability was observed in three of the allelic series. Viability testing of homozygous mutant kernels identified numerous dek mutations with various pleiotropic effects on seedling and plant development. The mutations described here presumably arose by insertion of a Mu transposon within a dek gene; thus, many of the affected loci are expected to be accessible to molecular cloning via transposon-tagging.

Scanlon, M. J.; Stinard, P. S.; James, M. G.; Myers, A. M.; Robertson, D. S.

1994-01-01

177

Responses of plants and invertebrate trophic groups to contrasting herbicide regimes in the Farm Scale Evaluations of genetically modified herbicide-tolerant crops  

Microsoft Academic Search

Effects of genetically modified herbicide-tolerant (GMHT) and conventional crop management on invert- ebrate trophic groups (herbivores, detritivores, pollinators, predators and parasitoids) were compared in beet, maize and spring oilseed rape sites throughout the UK. These trophic groups were influenced by season, crop species and GMHT management. Many groups increased twofold to fivefold in abundance between early and late summer, and

C. Hawes; A. J. Haughton; J. L. Osborne; D. B. Roy; S. J. Clark; J. N. Perry; P. Rothery; D. A. Bohan; D. R. Brooks; G. T. Champion; A. M. Dewar; M. S. Heard; I. P. Woiwod; R. E. Daniels; M. W. Young; A. M. Parish; R. J. Scott; L. G. Firbank; G. R. Squire

2003-01-01

178

Invertebrates and vegetation of field margins adjacent to crops subject to contrasting herbicide regimes in the Farm Scale Evaluations of genetically modified herbicide-tolerant crops  

Microsoft Academic Search

The effects of management of genetically modified herbicide-tolerant (GMHT) crops on adjacent field margins were assessed for 59 maize, 66 beet and 67 spring oilseed rape sites. Fields were split into halves, one being sown with a GMHT crop and the other with the equivalent conventional non-GMHT crop. Margin vegetation was recorded in three components of the field margins. Most

D. B. Roy; D. A. Bohan; A. J. Haughton; M. O. Hill; J. L. Osborne; S. J. Clark; J. N. Perry; P. Rothery; R. J. Scott; D. R. Brooks; G. T. Champion; C. Hawes; M. S. Heard; L. G. Firbank

2003-01-01

179

Maize genetic diversity and association mapping using transposable element insertion polymorphisms.  

PubMed

Transposable elements are the major component of the maize genome and presumably highly polymorphic yet they have not been used in population genetics and association analyses. Using the Transposon Display method, we isolated and converted into PCR-based markers 33 Miniature Inverted Repeat Transposable Elements (MITE) polymorphic insertions. These polymorphisms were genotyped on a population-based sample of 26 American landraces for a total of 322 plants. Genetic diversity was high and partitioned within and among landraces. The genetic groups identified using Bayesian clustering were in agreement with published data based on SNPs and SSRs, indicating that MITE polymorphisms reflect maize genetic history. To explore the contribution of MITEs to phenotypic variation, we undertook an association mapping approach in a panel of 367 maize lines phenotyped for 26 traits. We found a highly significant association between the marker ZmV1-9, on chromosome 1, and male flowering time. The variance explained by this association is consistent with a flowering delay of +123 degree-days. This MITE insertion is located at only 289 nucleotides from the 3' end of a Cytochrome P450-like gene, a region that was never identified in previous association mapping or QTL surveys. Interestingly, we found (i) a non-synonymous mutation located in the exon 2 of the gene in strong linkage disequilibrium with the MITE polymorphism, and (ii) a perfect sequence homology between the MITE sequence and a maize siRNA that could therefore potentially interfere with the expression of the Cytochrome P450-like gene. Those two observations among others offer exciting perspectives to validate functionally the role of this region on phenotypic variation. PMID:22350086

Zerjal, Tatiana; Rousselet, Agnès; Mhiri, Corinne; Combes, Valérie; Madur, Delphine; Grandbastien, Marie-Angèle; Charcosset, Alain; Tenaillon, Maud I

2012-05-01

180

Genetic analysis and characterization of a new maize association mapping panel for quantitative trait loci dissection  

Microsoft Academic Search

Association mapping based on the linkage disequilibrium provides a promising tool to identify genes responsible for quantitative\\u000a variations underlying complex traits. Presented here is a maize association mapping panel consisting of 155 inbred lines with\\u000a mainly temperate germplasm, which was phenotyped for 34 traits and genotyped using 82 SSRs and 1,536 SNPs. Abundant phenotypic\\u000a and genetic diversities were observed within

Xiaohong YangJianbing; Jianbing Yan; Trushar Shah; Marilyn L. Warburton; Qing Li; Lin Li; Yufeng Gao; Yuchao Chai; Zhiyuan Fu; Yi Zhou; Shutu Xu; Guanghong Bai; Yijiang Meng; Yanping Zheng; Jiansheng Li

2010-01-01

181

Metabolite profiling of maize grain: differentiation due to genetics and environment  

Microsoft Academic Search

A comparative metabolite profiling approach based on gas chromatography-mass spectrometry (GC\\/MS) was applied to investigate\\u000a the impact of genetic background, growing location and season on the chemical composition of maize grain. The metabolite profiling\\u000a protocol involved sub-fractionation of the metabolites and allowed the assessment of about 300 distinct analytes from different\\u000a chemical classes (polar to lipophilic), of which 167 could

Richard M. Röhlig; Joachim Eder; Karl-Heinz Engel

2009-01-01

182

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

PubMed

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. PMID:24521148

Simi?, Domagoj; Lepeduš, Hrvoje; Jurkovi?, Vlatka; Antunovi?, Jasenka; Cesar, Vera

2014-07-01

183

[Nutrition and health--genetically modified food].  

PubMed

The genetically modified (GM) crops cultivated at present have new properties of benefit to agriculture. It is expected that in the future GM crops will also be cultivated with more complex genetic modifications that are aimed at improving the nutritional and health value to the consumer. The safety assessment of GM foods before market approval is based on a comparison of the characteristics of the GM food with those of the conventional counterpart. Identified differences are thoroughly tested for their toxicological and nutritional consequences. Supplementary modern analytical techniques are being developed for the assessment of future complex GM foods. No cases of adverse health or nutritional effects in consumers have been reported for the existing generation of GM foods. The feasibility of post-market surveillance of (GM) foods, in order to identify small or chronic effects that have not been noticed in the pre-market phase, is being investigated, yet its value should not be overestimated. Surveillance can be informative in case of specific questions concerning certain products as long as the consumer intake is well documented. To this end traceability and labelling systems must be set up. PMID:12602068

Kuiper, H A; Kleter, G A; Kok, E J

2003-01-11

184

Genetic studies on cytoplasmic male sterility in maize  

SciTech Connect

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.

Laughnan, J.R.

1992-01-01

185

Genetic dissection of Al tolerance QTLs in the maize genome by high density SNP scan  

PubMed Central

Background Aluminum (Al) toxicity is an important limitation to food security in tropical and subtropical regions. High Al saturation on acid soils limits root development, reducing water and nutrient uptake. In addition to naturally occurring acid soils, agricultural practices may decrease soil pH, leading to yield losses due to Al toxicity. Elucidating the genetic and molecular mechanisms underlying maize Al tolerance is expected to accelerate the development of Al-tolerant cultivars. Results Five genomic regions were significantly associated with Al tolerance, using 54,455 SNP markers in a recombinant inbred line population derived from Cateto Al237. Candidate genes co-localized with Al tolerance QTLs were further investigated. Near-isogenic lines (NILs) developed for ZmMATE2 were as Al-sensitive as the recurrent line, indicating that this candidate gene was not responsible for the Al tolerance QTL on chromosome 5, qALT5. However, ZmNrat1, a maize homolog to OsNrat1, which encodes an Al3+ specific transporter previously implicated in rice Al tolerance, was mapped at ~40 Mbp from qALT5. We demonstrate for the first time that ZmNrat1 is preferentially expressed in maize root tips and is up-regulated by Al, similarly to OsNrat1 in rice, suggesting a role of this gene in maize Al tolerance. The strongest-effect QTL was mapped on chromosome 6 (qALT6), within a 0.5 Mbp region where three copies of the Al tolerance gene, ZmMATE1, were found in tandem configuration. qALT6 was shown to increase Al tolerance in maize; the qALT6-NILs carrying three copies of ZmMATE1 exhibited a two-fold increase in Al tolerance, and higher expression of ZmMATE1 compared to the Al sensitive recurrent parent. Interestingly, a new source of Al tolerance via ZmMATE1 was identified in a Brazilian elite line that showed high expression of ZmMATE1 but carries a single copy of ZmMATE1. Conclusions High ZmMATE1 expression, controlled either by three copies of the target gene or by an unknown molecular mechanism, is responsible for Al tolerance mediated by qALT6. As Al tolerant alleles at qALT6 are rare in maize, marker-assisted introgression of this QTL is an important strategy to improve maize adaptation to acid soils worldwide.

2014-01-01

186

Genetically Modified Organisms and Biodiversity: Assessing the Threats  

Microsoft Academic Search

Genetically Modified Organisms (GMOs) are those into whose genome a foreign well-characterized DNA from a different source (plant, animal or microorganism) has been stably inserted. Transgenic plants are a recognized ex- ample. Scientists genetically modify plants to: increase post-harvest life, resist biotic and abiotic stresses, improve plant nutrient qualities and use them as biofactories in pharmaceutical and vaccine production. For

Camilo Ayra Pardo

2003-01-01

187

Detection of genetically modified organisms by electrochemiluminescence PCR method  

Microsoft Academic Search

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.

Jinfeng Liu; Da Xing; Xingyan Shen; Debin Zhu

2004-01-01

188

Genetically modified organisms and visceral leishmaniasis.  

PubMed

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. PMID:24860575

Chhajer, Rudra; Ali, Nahid

2014-01-01

189

Genetically modified plants and human health  

PubMed Central

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.

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

2008-01-01

190

Genetically modified mouse models addressing gonadotropin function.  

PubMed

The development of genetically modified animals has been useful to understand the mechanisms involved in the regulation of the gonadotropin function. It is well known that alterations in the secretion of a single hormone is capable of producing profound reproductive abnormalities. Human chorionic gonadotropin (hCG) is a glycoprotein hormone normally secreted by the human placenta, and structurally and functionally it is related to pituitary LH. LH and hCG bind to the same LH/hCG receptor, and hCG is often used as an analog of LH to boost gonadotropin action. There are many physiological and pathological conditions where LH/hCG levels and actions are elevated. In order to understand how elevated LH/hCG levels may impact on the hypothalamic-pituitary-gonadal axis we have developed a transgenic mouse model with chronic hCG hypersecretion. Female mice develop many gonadal and extragonadal phenotypes including obesity, infertility, hyperprolactinemia, and pituitary and mammary gland tumors. This article summarizes recent findings on the mechanisms involved in pituitary gland tumorigenesis and hyperprolactinemia in the female mice hypersecreting hCG, in particular the relationship of progesterone with the hyperprolactinemic condition of the model. In addition, we describe the role of hyperprolactinemia as the main cause of infertility and the phenotypic abnormalities in these mice, and the use of dopamine agonists bromocriptine and cabergoline to normalize these conditions. PMID:24607250

Ratner, Laura D; Rulli, Susana B; Huhtaniemi, Ilpo T

2014-03-01

191

Genetically modified crops and food security.  

PubMed

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. PMID:23755155

Qaim, Matin; Kouser, Shahzad

2013-01-01

192

Genetically Modified Organisms and Visceral Leishmaniasis  

PubMed Central

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.

Chhajer, Rudra; Ali, Nahid

2014-01-01

193

Genetically Modified Crops and Food Security  

PubMed Central

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.

Qaim, Matin; Kouser, Shahzad

2013-01-01

194

Construction of a reference plasmid containing ten targets for the detection of genetically modified crops.  

PubMed

Standard reference molecules play a significant role for the detection of genetically modified (GM) crops and products. The newest reference molecules should catch up with the rapid development of GM crops in the world. In this work, a reference plasmid containing ten targets from GM soybean, maize and cotton was constructed on the basis of the pTLE8 harboring eight targets only from GM soybean and cotton. Three target segments of the Bt176 event-specific 3'-junction (Bt176G3'), MON810 event-specific 3'-junction (MON810G3') and the endogenous maize Hmg genes, were fused into the 890 bp fragment by overlap extension PCR. The CP4 EPSPS gene in the plasmid pTLE8 previously constructed in our laboratory was replaced with above fusion fragment, thus generating a new plasmid pTLH10 containing ten target genes from GM soybean, maize and cotton. The PCR efficiencies with pTLH10 as a calibrator ranged from 93.3% to 99.9% for the standard curves of the Bt176G3', MON810G3' and Hmg genes. The standard deviation (SD) values of repeatability were from 0.04 to 0.8 for three different days and from 0.12 to 1.14 for one day, respectively. These results indicated that the reference plasmid constructed in this work is also suitable for the identification of GM maize, and would be an important tool to establish a feasible identification management for various GM crops components. PMID:23085154

Wang, Xiumin; Teng, Da; Xi, Di; Guan, Qingfeng; Wang, Jianhua

2013-01-01

195

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

PubMed Central

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.

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

1978-01-01

196

Genetically Modified Food: Golden Rice: Help or Hazard?  

NSDL National Science Digital Library

This online article is from the Museum's Seminars on Science, a series of distance-learning courses designed to help educators meet the new national science standards. Genetically Modified Food: Golden Rice, part of the Genetics, Genomics, Genethics seminar, briefly covers genetically engineering rice to help combat blindness due to vitamin A deficiencies and the ethical and environmental concerns of this proposal.

197

The genetic basis of natural variation for iron homeostasis in the maize IBM population  

PubMed Central

Background Iron (Fe) deficiency symptoms in maize (Zea mays subsp. mays) express as leaf chlorosis, growth retardation, as well as yield reduction and are typically observed when plants grow in calcareous soils at alkaline pH. To improve our understanding of genotypical variability in the tolerance to Fe deficiency-induced chlorosis, the objectives of this study were to (i) determine the natural genetic variation of traits related to Fe homeostasis in the maize intermated B73 × Mo17 (IBM) population, (ii) to identify quantitative trait loci (QTLs) for these traits, and (iii) to analyze expression levels of genes known to be involved in Fe homeostasis as well as of candidate genes obtained from the QTL analysis. Results In hydroponically-grown maize, a total of 47 and 39 QTLs were detected for the traits recorded under limited and adequate supply of Fe, respectively. Conclusions From the QTL results, we were able to identify new putative candidate genes involved in Fe homeostasis under a deficient or adequate Fe nutritional status, like Ferredoxin class gene, putative ferredoxin PETF, metal tolerance protein MTP4, and MTP8. Furthermore, our expression analysis of candidate genes suggested the importance of trans-acting regulation for 2’-deoxymugineic acid synthase 1 (DMAS1), nicotianamine synthase (NAS3, NAS1), formate dehydrogenase 1 (FDH1), methylthioribose-1-phosphate isomerase (IDI2), aspartate/tyrosine/aromatic aminotransferase (IDI4), and methylthioribose kinase (MTK).

2014-01-01

198

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

PubMed

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. PMID:22956211

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

199

Genetically modified crops: Brazilian law and overview.  

PubMed

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. PMID:25061747

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

2014-01-01

200

Genetic diversity analysis of elite European maize (Zea mays L.) inbred lines using AFLP, SSR, and SNP markers reveals ascertainment bias for a subset of SNPs.  

PubMed

Recent advances in high-throughput sequencing technologies have triggered a shift toward single-nucleotide polymorphism (SNP) markers. A systematic bias can be introduced if SNPs are ascertained in a small panel of genotypes and then used for characterizing a larger population (ascertainment bias). With the objective of evaluating a potential ascertainment bias of the Illumina MaizeSNP50 array with respect to elite European maize dent and flint inbred lines, we compared the genetic diversity among these materials based on 731 amplified fragment length polymorphisms (AFLPs), 186 simple sequence repeats (SSRs), 41,434 SNPs of the MaizeSNP50 array (SNP-A), and two subsets of it, i.e., 30,068 Panzea (SNP-P) and 11,366 Syngenta markers (SNP-S). We evaluated the bias effects on major allele frequency, allele number, gene diversity, modified Roger's distance (MRD), and on molecular variance (AMOVA). We revealed ascertainment bias in SNP-A, compared to AFLPs and SSRs. It affected especially European flint lines analyzed with markers (SNP-S) specifically developed to maximize differences among North American dent germplasm. The bias affected all genetic parameters, but did not substantially alter the relative distances between inbred lines within groups. For these reasons, we conclude that the SNP markers of the MaizeSNP50 array can be employed for breeding purposes in the investigated material. However, attention should be paid in case of comparisons between genotypes belonging to different heterotic groups. In this case, it is advisable to prefer a marker subset with potentially low ascertainment bias, like in our case the SNP-P marker set. PMID:22945268

Frascaroli, Elisabetta; Schrag, Tobias A; Melchinger, Albrecht E

2013-01-01

201

Methodological scheme for designing the monitoring of genetically modified crops at the regional scale.  

PubMed

According to EC regulations the deliberate release of genetically modified (GM) crops into the agro-environment needs to be accompanied by environmental monitoring to detect potential adverse effects, e.g. unacceptable levels of gene flow from GM to non-GM crops, or adverse effects on single species or species groups thus reducing biodiversity. There is, however, considerable scientific and public debate on how GM crops should be monitored with sufficient accuracy, discussing questions of potential adverse effects, agro-environmental variables or indicators to be monitored and respective detection methods; Another basic component, the appropriate number and location of monitoring sites, is hardly considered. Currently, no consistent GM crop monitoring approach combines these components systematically. This study focuses on and integrates spatial agro-environmental aspects at a landscape level in order to design monitoring networks. Based on examples of environmental variables associated with the cropping of Bt-Maize (Zea maize L.), herbicide-tolerant (HT) winter oilseed rape (Brassica napus L.), HT sugar beet (Beta vulgaris L.), and starch-modified potato (Solanum tuberosum L.), we develop a transferable framework and assessment scheme that comprises anticipated adverse environmental effects, variables to be measured and monitoring methods. These we integrate with a rule-based GIS (geographic information system) analysis, applying widely available spatial area and point information from existing environmental networks. This is used to develop scenarios with optimised regional GM crop monitoring networks. PMID:16311819

Graef, F; Züghart, W; Hommel, B; Heinrich, U; Stachow, U; Werner, A

2005-12-01

202

[Assessment of allergenicity of genetically modified food crops].  

PubMed

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. PMID:22373855

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

2012-03-01

203

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

PubMed

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. PMID:12083276

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

2002-01-01

204

Unraveling the genetic architecture of subtropical maize (Zea mays L.) lines to assess their utility in breeding programs  

PubMed Central

Background Maize is an increasingly important food crop in southeast Asia. The elucidation of its genetic architecture, accomplished by exploring quantitative trait loci and useful alleles in various lines across numerous breeding programs, is therefore of great interest. The present study aimed to characterize subtropical maize lines using high-quality SNPs distributed throughout the genome. Results We genotyped a panel of 240 subtropical elite maize inbred lines and carried out linkage disequilibrium, genetic diversity, population structure, and principal component analyses on the generated SNP data. The mean SNP distance across the genome was 70 Kb. The genome had both high and low linkage disequilibrium (LD) regions; the latter were dominant in areas near the gene-rich telomeric portions where recombination is frequent. A total of 252 haplotype blocks, ranging in size from 1 to 15.8 Mb, were identified. Slow LD decay (200–300 Kb) at r 2 ???0.1 across all chromosomes explained the selection of favorable traits around low LD regions in different breeding programs. The association mapping panel was characterized by strong population substructure. Genotypes were grouped into three distinct clusters with a mean genetic dissimilarity coefficient of 0.36. Conclusions The genotyped panel of subtropical maize lines characterized in this study should be useful for association mapping of agronomically important genes. The dissimilarity uncovered among genotypes provides an opportunity to exploit the heterotic potential of subtropical elite maize breeding lines.

2013-01-01

205

Use of rice straw and radiation-modified maize starch/acrylonitrile in the treatment of wastewater.  

PubMed

Graft copolymerization of acrylonitrile onto maize starch by a simultaneous irradiation technique using gamma-rays as the initiator was studied with regard to the various parameters of importance: the monomer-to-maize starch ratio and total dose (kGy). The water absorption of the modified maize starch was measured. The starch modified by acrylonitrile gives low water absorbance. Conversion of the copolymer to the amidoxime form gives high swelling. The gel (%) and the grafting efficiency were measured. An investigation was carried out to study the adsorption of basic violet 7, basic blue 3, direct yellow 50 and acid red 37 from aqueous solutions by the water-insoluble modified starch containing amidoxime groups and rice straw. The effects of initial pH of the solution, pollutant concentration and treatment time on the adsorption were studied and it was found that the maximum adsorption was at 1:2 (starch/acrylonitrile) at irradiation dose 30 kGy. PMID:16300882

Abdel-Aal, S E; Gad, Y H; Dessouki, A M

2006-02-28

206

High Genetic Variability of Herbivore-Induced Volatile Emission within a Broad Range of Maize Inbred Lines1  

PubMed Central

Maize plants (Zea mays) attacked by caterpillars release a mixture of odorous compounds that attract parasitic wasps, natural enemies of the herbivores. We assessed the genetic variability of these induced volatile emissions among 31 maize inbred lines representing a broad range of genetic diversity used by breeders in Europe and North America. Odors were collected from young plants that had been induced by injecting them with caterpillar regurgitant. Significant variation among lines was found for all 23 volatile compounds included in the analysis: the lines differed enormously in the total amount of volatiles emitted and showed highly variable odor profiles distinctive of each genotype. Principal component analysis performed on the relative quantities of particular compounds within the blend revealed clusters of highly correlated volatiles, which may share common metabolic pathways. European and American lines belonging to established heterotic groups were loosely separated from each other, with the most clear-cut difference in the typical release of (E)-?-caryophyllene by European lines. There was no correlation between the distances among the lines based on their odor profiles and their respective genetic distances previously assessed by neutral RFLP markers. This most comprehensive study to date on intraspecific variation in induced odor emission by maize plants provides a further example of the remarkably high genetic diversity conserved within this important crop plant. A better understanding of the genetic control of induced odor emissions may help in the development of maize varieties particularly attractive to parasitoids and other biological control agents and perhaps more repellent for herbivores.

Degen, Thomas; Dillmann, Christine; Marion-Poll, Frederic; Turlings, Ted C.J.

2004-01-01

207

Genetic diversity for restriction fragment length polymorphisms and heterosis for two diallel sets of maize inbreds  

Microsoft Academic Search

Changes that may have occurred over the past 50 years of hybrid breeding in maize (Zea maize L.) with respect to heterosis for yield and heterozygosity at the molecular level are of interest to both maize breeders and quantitative geneticists. The objectives of this study were twofold: The first, to compare two diallels produced from six older maize inbreds released

A. E. Melchinger; M. Lee; K. R. Lamkey; A. R. Hallauer; W. L. Woodman

1990-01-01

208

Genetic factors required to maintain repression of a paramutagenic maize pl1 allele.  

PubMed Central

A genetic screen identified two novel gene functions required to maintain mitotically and meiotically heritable gene silencing associated with paramutation of the maize purple plant 1 (pl1) locus. Paramutation at pl1 leads to heritable alterations of pl1 gene regulation; the Pl-Rhoades (Pl-Rh) allele, which typically confers strong pigmentation to juvenile and adult plant structures, changes to a lower expression state termed Pl'-mahogany (Pl'). Paramutation spontaneously occurs at low frequencies in Pl-Rh homozygotes but always occurs when Pl-Rh is heterozygous with Pl'. We identified four mutations that caused increased Pl' pigment levels. Allelism tests revealed that three mutations identified two new maize loci, required to maintain repression 1 (rmr1) and rmr2 and that the other mutation represents a new allele of the previously described mediator of paramutation 1 (mop1) locus. RNA levels from Pl' are elevated in rmr mutants and genetic tests demonstrate that Pl' can heritably change back to Pl-Rh in rmr mutant individuals at variable frequencies. Pigment levels controlled by two pl1 alleles that do not participate in paramutation are unaffected in rmr mutants. These results suggest that RMR functions are intimately involved in maintaining the repressed expression state of paramutant Pl' alleles. Despite strong effects on Pl' repression, rmr mutant plants have no gross developmental abnormalities even after several generations of inbreeding, implying that RMR1 and RMR2 functions are not generally required for developmental homeostasis.

Hollick, J B; Chandler, V L

2001-01-01

209

Gene Flow in Genetically Modified Wheat  

PubMed Central

Understanding gene flow in genetically modified (GM) crops is critical to answering questions regarding risk-assessment and the coexistence of GM and non-GM crops. In two field experiments, we tested whether rates of cross-pollination differed between GM and non-GM lines of the predominantly self-pollinating wheat Triticum aestivum. In the first experiment, outcrossing was studied within the field by planting “phytometers” of one line into stands of another line. In the second experiment, outcrossing was studied over distances of 0.5–2.5 m from a central patch of pollen donors to adjacent patches of pollen recipients. Cross-pollination and outcrossing was detected when offspring of a pollen recipient without a particular transgene contained this transgene in heterozygous condition. The GM lines had been produced from the varieties Bobwhite or Frisal and contained Pm3b or chitinase/glucanase transgenes, respectively, in homozygous condition. These transgenes increase plant resistance against pathogenic fungi. Although the overall outcrossing rate in the first experiment was only 3.4%, Bobwhite GM lines containing the Pm3b transgene were six times more likely than non-GM control lines to produce outcrossed offspring. There was additional variation in outcrossing rate among the four GM-lines, presumably due to the different transgene insertion events. Among the pollen donors, the Frisal GM line expressing a chitinase transgene caused more outcrossing than the GM line expressing both a chitinase and a glucanase transgene. In the second experiment, outcrossing after cross-pollination declined from 0.7–0.03% over the test distances of 0.5–2.5 m. Our results suggest that pollen-mediated gene flow between GM and non-GM wheat might only be a concern if it occurs within fields, e.g. due to seed contamination. Methodologically our study demonstrates that outcrossing rates between transgenic and other lines within crops can be assessed using a phytometer approach and that gene-flow distances can be efficiently estimated with population-level PCR analyses.

Rieben, Silvan; Kalinina, Olena; Schmid, Bernhard; Zeller, Simon L.

2011-01-01

210

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

PubMed Central

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.

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

211

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

PubMed

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. PMID:22120952

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

212

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

PubMed Central

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. A potential approach for improving stalk strength and crop yields in commercial maize lines may be to introgress favorable alleles of the locus that was found to have the largest effect on rind penetrometer resistance (qRPR3-1).

2014-01-01

213

Haplotype structure strongly affects recombination in a maize genetic interval polymorphic for Helitron and retrotransposon insertions  

PubMed Central

We have asked here how the remarkable variation in maize haplotype structure affects recombination. We compared recombination across a genetic interval of 9S in 2 highly dissimilar heterozygotes that shared 1 parent. The genetic interval in the common haplotype is ?100 kb long and contains 6 genes interspersed with gene-fragment-bearing Helitrons and retrotransposons that, together, comprise 70% of its length. In one heterozygote, most intergenic insertions are homozygous, although polymorphic, enabling us to determine whether any recombination junctions fall within them. In the other, most intergenic insertions are hemizygous and, thus, incapable of homologous recombination. Our analysis of the frequency and distribution of recombination in the interval revealed that: (i) Most junctions were circumscribed to the gene space, where they showed a highly nonuniform distribution. In both heterozygotes, more than half of the junctions fell in the stc1 gene, making it a clear recombination hotspot in the region. However, the genetic size of stc1 was 2-fold lower when flanked by a hemizygous 25-kb retrotransposon cluster. (ii) No junctions fell in the hypro1 gene in either heterozygote, making it a genic recombination coldspot. (iii) No recombination occurred within the gene fragments borne on Helitrons nor within retrotransposons, so neither insertion class contributes to the interval's genetic length. (iv) Unexpectedly, several junctions fell in an intergenic region not shared by all 3 haplotypes. (v) In general, the ability of a sequence to recombine correlated inversely with its methylation status. Our results show that haplotypic structural variability strongly affects the frequency and distribution of recombination events in maize.

He, Limei; Dooner, Hugo K.

2009-01-01

214

Genetically Modified Rice Adoption: Implications for Welfare and Poverty Alleviation  

Microsoft Academic Search

The first generation of genetically modified (GM) crop varieties sought to increase farmer profitability through cost reductions or higher yields. The next generation of GM food research is focusing also on breeding for attributes of interest to consumers, beginning with ‘golden rice’, which has been genetically engineered to contain a higher level of vitamin A and thereby boost the health

Kym Anderson; Lee Ann Jackson

2005-01-01

215

Modified Genetic Algorithm for Parameter Selection of Compartmental Models  

Microsoft Academic Search

A modified genetic algorithm has been developed for the task of optimal parameter selection for compartmental models. As a case study, a predictive model of the emerging health threat of obesity in America was developed which incorporated varying levels of three treatment strategies in an attempt to decrease the amount of overweight Americans over a ten-year period. The genetic algorithm

Neil A. Shah; Richard A. Moffitt; May D. Wang

2007-01-01

216

Review: genetically modified plants for the promotion of human health  

Microsoft Academic Search

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

Keiko Yonekura-Sakakibara; Kazuki Saito

2006-01-01

217

The Genetic Architecture of Response to Long-Term Artificial Selection for Oil Concentration in the Maize Kernel  

Microsoft Academic Search

In one of the longest-running experiments in biology, researchers at the University of Illinois have selected for altered composition of the maize kernel since 1896. Here we use an association study to infer the genetic basis of dramatic changes that occurred in response to selection for changes in oil concentration. The study population was produced by a cross between the

Cathy C. Laurie; Scott D. Chasalow; John R. LeDeaux; Robert McCarroll; David Bush; Brian Hauge; Chaoqiang Lai; Darryl Clark; Torbert R. Rocheford; John W. Dudley

2004-01-01

218

Modifier Genes and the Plasticity of Genetic Networks in Mice  

PubMed Central

Modifier genes are an integral part of the genetic landscape in both humans and experimental organisms, but have been less well explored in mammals than other systems. A growing number of modifier genes in mouse models of disease nonetheless illustrate the potential for novel findings, while new technical advances promise many more to come. Modifier genes in mouse models include induced mutations and spontaneous or wild-derived variations captured in inbred strains. Identification of modifiers among wild-derived variants in particular should detect disease modifiers that have been shaped by selection and might therefore be compatible with high fitness and function. Here we review selected examples and argue that modifier genes derived from natural variation may provide a bias for nodes in genetic networks that have greater intrinsic plasticity and whose therapeutic manipulation may therefore be more resilient to side effects than conventional targets.

Hamilton, Bruce A.; Yu, Benjamin D.

2012-01-01

219

The Detection of Genetically Modified Organisms: An Overview  

Microsoft Academic Search

Genetically modified organisms (GMOs) are those whose genetic material has been altered by the insertion of a new gene or\\u000a by the deletion of an existing one(s). Modern biotechnology, in particular, the rise of genetic engineering, has supported\\u000a the development of GMOs suitable for research purposes and practical applications (Gepts, 2002; Novoselova,Meuwissen, & Huirne,\\u000a 2007; Sakakibara & Saito, 2006). For

Jaroslava Ovesná; Katerina Demnerová; Vladimíra Pouchová

2008-01-01

220

Tropical Maize: Exploiting Maize Genetic Diversity to Develop a Novel Annual Crop for Lignocellulosic Biomass and Sugar Production  

Microsoft Academic Search

\\u000a Maize (Zea mays L.) is truly a remarkable crop species, having been adapted from its tropical origins to a wide diversity of environments\\u000a and end uses. According to the Food and Agriculture Organization of the United Nations FAOSTAT webpage, 792 million metric\\u000a tons of maize were produced worldwide in 2007, making it the world’s highest yielding grain crop (http:\\/\\/faostat.fao.org\\/site\\/339\\/default.aspx).\\u000a When

Wendy G. White; Stephen P. Moose; Clifford F. Weil; Maureen C. McCann; Nicholas C. Carpita

221

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

PubMed

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. PMID:19943159

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

222

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

PubMed

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. PMID:22295567

Griadunov, D A; Getman, I A; Chizhova, S I; Mikha?lovich, V M; Zasedatelev, A S; Romanov, G A

2011-01-01

223

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

PubMed

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. PMID:16042293

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

2005-06-01

224

Complexity and Genetic Variability of Heat-Shock Protein Expression in Isolated Maize Microspores.  

PubMed Central

The expression of heat-shock proteins (HSPs) in isolated maize (Zea mays L.) microspores has been investigated using high-resolution two-dimensional electrophoresis coupled to immunodetection and fluorography of in vivo synthesized proteins. To this end, homogeneous and viable populations of microspores have been purified in sufficient amounts for molecular analysis from plants grown in controlled conditions. Appropriate conditions for thermal stress application have been defined. The analysis revealed that isolated microspores from maize display a classical heat-shock response characterized by the repression of the normal protein synthesis and the expression of a set of HSPs. A high complexity of the response was demonstrated, with numerous different HSPs being resolved in each known major HSP molecular weight class. However, the extent of this heat-shock response is limited in that some of these HSPs do not accumulate at high levels following temperature elevation. Comparative analysis of the heat-shock responses of microspores isolated from five genotypes demonstrated high levels of genetic variability. Furthermore, many HSPs were detected in microspores at control temperature, indicating a possible involvement of these proteins in pollen development at stages close to first pollen mitosis.

Magnard, J. L.; Vergne, P.; Dumas, C.

1996-01-01

225

Development and validation of real-time PCR screening methods for detection of cry1A.105 and cry2Ab2 genes in genetically modified organisms  

Microsoft Academic Search

Primers and probes were developed for the element-specific detection of cry1A.105 and cry2Ab2 genes, based on their DNA sequence as present in GM maize MON89034. Cry genes are present in many genetically modified (GM) plants and they are important targets for developing GMO element-specific\\u000a detection methods. Element-specific methods can be of use to screen for the presence of GMOs in

Andréia Z. Dinon; Theo W. Prins; Jeroen P. van Dijk; Ana Carolina M. Arisi; Ingrid M. J. Scholtens; Esther J. Kok

2011-01-01

226

Intrathymic implants of genetically modified fibroblasts  

Microsoft Academic Search

Implantation of autologous rodent fibro- blasts genetically altered to express human growth hor- mone has recently been shown to be a feasible approach to the delivery of new gene products in somatic gene ther- apy. However, the novel gene product elicited in its recipients an intense antibody response that would have curtailed the effectiveness ofsuch therapy.The possibility of inducing tolerance

A. M. P. BEHABA; A. J. WESIUYrT

227

The fate of transgenic sequences present in genetically modified plant products in fish feed, investigating the survival of GM soybean DNA fragments during feeding trials in Atlantic salmon, Salmo salar L  

Microsoft Academic Search

Vegetable protein sources like soybeans, canola and maize gluten are good alternatives to fish meal. However, a large proportion of such products available on the international market may possess genetically modified (GM) components. This report concerns a study to investigate the fate and survival of ingested GM soy DNA fragments (120 and 195 bp) and a 180-bp fragment of the

Monica Sanden; Ian J Bruce; M. Azizur Rahman; Gro-Ingunn Hemre

2004-01-01

228

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

PubMed

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)-?-caryophyllene and ?-humulene, was found to compromise seed germination, plant growth and yield. These physiological costs provide a possible explanation for the inducibility of an (E)-?-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)-?-caryophyllene and ?-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. PMID:23425633

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

229

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

PubMed

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. PMID:19399482

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

2009-07-01

230

Genetically Modified Food: Knowledge and Attitude of Teachers and Students  

NASA Astrophysics Data System (ADS)

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.

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

2010-10-01

231

Perceived naturalness and acceptance of genetically modified food.  

PubMed

This study examines people's acceptance of genetically modified (GM) food. Results suggest that GM acceptance depends most on how natural the genetically modified product is perceived and not directly on how natural the non-GM product is seen. A GM product that is perceived as more natural is more likely to be accepted than a GM product that is perceived as less natural. The extent to which GM affects the perceived naturalness of a product partly depends on the kind of product. PMID:15896875

Tenbült, Petra; de Vries, Nanne K; Dreezens, Ellen; Martijn, Carolien

2005-08-01

232

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

PubMed

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. PMID:18289760

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

233

A PIEZOELECTRIC AFFINITY BIOSENSOR FOR GENETICALLY MODIFIED ORGANISMS (GMOs) DETECTION  

Microsoft Academic Search

A piezoelectric affinity sensor, based on DNA hybridisation has been studied for applications to Genetically Modified Organisms (GMOs) detection. The thiol\\/dextran modified surfaces were coupled to streptavidin for immobilising 5'-biotinyltead probes (25-mer). The probes sequences were respectively internal to the amplified product of P35S and T-NOS. These target sequences were chosen on the base of their wide presence in GMOs.

M. Minunni; S. Tombelli; S. Pratesi; M. Mascini; P. Piatti; P. Bogani; M. Buiatti

2001-01-01

234

Genetically modified plants for tactical systems applications  

NASA Astrophysics Data System (ADS)

Plants are ubiquitous in the environment and have the ability to respond to their environment physiologically and through altered gene expression profiles (they cannot walk away). In addition, plant genetic transformation techniques and genomic information in plants are becoming increasingly advanced. We have been performing research to express the jellyfish green fluorescent protein (GFP) in plants. GFP emits green light when excited by blue or UV light. In addition, my group and collaborators have developed methods to detect GFP in plants by contact instruments and at a standoff. There are several tactical uses for this technology. Some obvious applications are using plants as sentinels for detecting biological and chemical warfare agents or their derivatives from a remote platform, as well as detecting explosives. Another tactical application is covert monitoring using individual plants. Different methods to detect GFP in transgenic plants will be discussed.

Stewart, C. Neal, Jr.

2002-08-01

235

Huntingtin Interacting Proteins Are Genetic Modifiers of Neurodegeneration  

PubMed Central

Huntington's disease (HD) is a fatal neurodegenerative condition caused by expansion of the polyglutamine tract in the huntingtin (Htt) protein. Neuronal toxicity in HD is thought to be, at least in part, a consequence of protein interactions involving mutant Htt. We therefore hypothesized that genetic modifiers of HD neurodegeneration should be enriched among Htt protein interactors. To test this idea, we identified a comprehensive set of Htt interactors using two complementary approaches: high-throughput yeast two-hybrid screening and affinity pull down followed by mass spectrometry. This effort led to the identification of 234 high-confidence Htt-associated proteins, 104 of which were found with the yeast method and 130 with the pull downs. We then tested an arbitrary set of 60 genes encoding interacting proteins for their ability to behave as genetic modifiers of neurodegeneration in a Drosophila model of HD. This high-content validation assay showed that 27 of 60 orthologs tested were high-confidence genetic modifiers, as modification was observed with more than one allele. The 45% hit rate for genetic modifiers seen among the interactors is an order of magnitude higher than the 1%–4% typically observed in unbiased genetic screens. Genetic modifiers were similarly represented among proteins discovered using yeast two-hybrid and pull-down/mass spectrometry methods, supporting the notion that these complementary technologies are equally useful in identifying biologically relevant proteins. Interacting proteins confirmed as modifiers of the neurodegeneration phenotype represent a diverse array of biological functions, including synaptic transmission, cytoskeletal organization, signal transduction, and transcription. Among the modifiers were 17 loss-of-function suppressors of neurodegeneration, which can be considered potential targets for therapeutic intervention. Finally, we show that seven interacting proteins from among 11 tested were able to co-immunoprecipitate with full-length Htt from mouse brain. These studies demonstrate that high-throughput screening for protein interactions combined with genetic validation in a model organism is a powerful approach for identifying novel candidate modifiers of polyglutamine toxicity.

Becklin, Robert R; Chettier, Rakesh; Bell, Russell; Phansalkar, Amit; Strand, Andrew; Torcassi, Cameron; Savage, Justin; Hurlburt, Anthony; Cha, Guang-Ho; Ukani, Lubna; Chepanoske, Cindy Lou; Zhen, Yuejun; Sahasrabudhe, Sudhir; Olson, James; Kurschner, Cornelia; Ellerby, Lisa M; Peltier, John M; Botas, Juan; Hughes, Robert E

2007-01-01

236

The Future of Maize  

Microsoft Academic Search

In the near future, maize will continue to expand and diversify as a research model, as an industrial resource and as a crop\\u000a for feed and fuel. The generation of the first maize genome sequence, followed by great improvements in genome sequencing\\u000a technology, will allow the exceptional genetic diversity of maize to be described in multiple sequenced genomes. Maize will

Jeffrey L. Bennetzen

237

Maize Glutamine Synthetase Cdnas: Isolation by Direct Genetic Selection in Escherichia Coli  

PubMed Central

Maize glutamine synthetase cDNA clones were isolated by genetic selection for functional rescue of an Escherichia coli ?glnA mutant growing on medium lacking glutamine. The Black Mexican Sweet cDNA library used in this study was constructed in pUC13 such that cDNA sense strands were transcribed under the control of the lac promoter. E. coli ?glnA cells were transformed with cDNA library plasmid DNA, grown briefly in rich medium to allow phenotypic expression of the cDNAs and the pUC13 amp(r) gene, and challenged to grow on agar medium lacking glutamine. Large numbers of glutamine synthetase cDNA clones have been identified in individual 150-mm Petri dishes; all characterized cDNA clones carry complete coding sequences. Two cDNAs identical except for different 5' and 3' termini have been sequenced. The major open reading frame predicts a protein with an amino acid sequence that exhibits striking similarity to the amino acid sequences of the predicted products of previously sequenced eukaryotic glutamine synthetase cDNAs and genes. In addition, the maize glutamine synthetase cDNAs were shown to contain a 5' mini-ORF of 29 codons separated by 37 nucleotide pairs from the major ORF. This mini-ORF was shown not to be essential for the functional rescue of the E. coli ?glnA mutant. Expression of the cDNAs in E. coli is presumed to be due to the function of a polycistronic hybrid lac messenger RNA or translational fusions encoded by the pUC plasmids. Proteins of the expected sizes encoded by two different pUC clones were shown to react with antibodies to tobacco glutamine synthetase.

Snustad, D. P.; Hunsperger, J. P.; Chereskin, B. M.; Messing, J.

1988-01-01

238

Early Institutionalization: Neurobiological Consequences and Genetic Modifiers  

PubMed Central

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.

Drury, Stacy; McLaughlin, Kate; Almas, Alisa

2011-01-01

239

Therapeutic potential of genetically modified mesenchymal stem cells  

Microsoft Academic Search

Bone marrow-derived mesenchymal stem cells (MSC) are multipotent adult stem cells of mesodermal origin localized within the bone marrow compartment. MSC possess multilineage property making them useful for a number of potential therapeutic applications. MSC can be isolated from the bone marrow, expanded in culture and genetically modified to serve as cell carriers for local or systemic therapy. Despite their

S Kumar; D Chanda; S Ponnazhagan

2008-01-01

240

Genetically modified tumour vaccines (GMTV) in melanoma clinical trials  

Microsoft Academic Search

Since melanoma is a model immunogenic malignancy incurable in the disseminated phase of its natural course different immunotherapeutic approaches are tested in clinical trials. A number of tumour vaccines genetically modified (GMTV), with various immunostimulatory factors, are tested in phase I\\/II clinical trials. These factors include cytokines, tumour antigens (TA), costimulatory molecules or HLA antigens. We have designed a novel,

Sergiusz Nawrocki; Pawe? Murawa; Julian Malicki; Malgorzata Kapcinska; Katarzyna Gryska; Dariusz Izycki; Aldona Kaczmarek; Maria Laciak; Anna Czapczyk; Aldona Karczewska; Stefan Rose-John; Andrzej Mackiewicz

2000-01-01

241

Gender modulates cardiac phenotype development in genetically modified mice  

Microsoft Academic Search

Recent research using genetically modified mice has revealed significant sex differences in cardiac phenotypes. In the majority of strains, females display a lower mortality, less severe hypertrophy, better preserved function and mitigated cardiac pathology compared with male counterparts. Thus, gender is an independent determinant for the development of cardiac phenotype in murine models. While there is strong evidence for estrogen

Xiao-Jun Du

2004-01-01

242

Proposals for nutritional assessments of feeds from genetically modified plants  

Microsoft Academic Search

The cultivation of genetically modified plants (GMP) increased from 1.7 to 81 million. ha from 1996 to 2004 (James, 2004). Scientists and farmers, but also consumers, are asking for a nutritional assessment, including safety aspects, of feeds from those plants. Substantial equivalence was created as a framework for the compositional assessment of feeds from GMP of the so-called first generation

G. Flachowsky; H. Böhme

243

Detection approaches for genetically modified organisms in foods  

Microsoft Academic Search

This review examines the various detection strategies for genetically modified organisms (GMOs) in food products. It begins with a brief discussion of the issues related to the technology especially the risks and public concerns. An introduction to the biological aspects of the major GMOs then follows. The bulk of the review is concerned with the different approaches toward detection: (a)

Anil K. Deisingh; Neela Badrie

2005-01-01

244

Genetically modified organisms (GMO) in bioremediation and legislation  

Microsoft Academic Search

Some authors expect genetically modified organisms (GMO) to bring a breakthrough in bioremediation. Besides biochemistry and microbial ecology, legislation and biosafety should be considered in this regard. World wide rules request risk assessment to be performed before any release of GMO to the environment. Recently, the protocol has been negotiated by UNEP to the Convention of Biological Diversity (CBD), which

Jaroslav Drobn??k

1999-01-01

245

Genetically Modified Organisms in Peasant Farming: Social Impact and Equity  

Microsoft Academic Search

This paper's first objective is to discuss the potential social impact of the diffusion of genetically modified organisms (GMOs) into peasant sectors of less developed countries. While unwanted environmental impacts of the new technology can be partially assessed in controlled, experimental settings, assessment of social impacts requires experience and observation in particular farming systems. Owing to the absence of direct

STEPHEN B. BRUSH

2001-01-01

246

Electrochemiluminescence polymerase chain reaction detection of genetically modified organisms  

Microsoft Academic Search

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. Electrochemiluminescence (ECL) method is a chemiluminescent (CL) reaction of species generated electrochemically on an electrode surface. It is a highly efficient and accurate detection method. In this paper, ECL

Jinfeng Liu; Da Xing; Xingyan Shen; Debin Zhu

2005-01-01

247

Enacting Closure in the Environmental Control of Genetically Modified Organisms  

Microsoft Academic Search

One of the challenges of environmental law is to turn complex realities into coherent regulatory phenomena. The task requires ordering and boundary making. Motivated by this fact, this article studies the various types of closure through which releases of genetically modified organisms (GMOs) are made manageable in the European Union. We analyse the legal framework for controlling environmental releases of

Helena Valve; Jussi Kauppila

2008-01-01

248

Surface plasmon resonance biosensor for genetically modified organisms detection  

Microsoft Academic Search

The development of a surface plasmon resonance (SPR) affinity biosensor based on DNA hybridisation is described. This biosensor has been applied to genetically modified organisms (GMOs) detection. Single stranded DNA (ssDNA) probes were immobilised on the sensor chip of an SPR device and the hybridisation between the immobilised probe and the complementary sequence (target) was monitored. The probe sequences were

Elisa Mariotti; Maria Minunni; Marco Mascini

2002-01-01

249

Releasing genetically modified organisms: will any harm outweigh any advantage?  

Microsoft Academic Search

Summary 1. The public debate about genetically modified organisms has concentrated largely on concerns about food safety and potential risks to the environment. In both cases there appears to be an assumption that existing crops and animals are safe. I discuss the experience we have to date from traditional methods and conclude that most concerns about environmental harm are more

John E. Beringer

2000-01-01

250

Regulation of Genetically Modified Organisms in the European Union  

Microsoft Academic Search

To be successful, laws that regulate genetically modified organisms (GMOs) must help society decide rationally when to pause and when to proceed in adopting new biotechnological developments. In the context of European Union (EU) institutions and lawmaking procedures, this article examines European Community (EC) legal measures that govern the contained use, deliberate release, and labeling of GMOs. To illustrate Member

MARGARET ROSSO GROSSMAN; A. BRYAN ENDRES

2000-01-01

251

Regulatory control of genetically modified (GM) foods: likely developments  

Microsoft Academic Search

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,

Anne Constable

2002-01-01

252

Examining Consumer Behavior Toward Genetically Modified (GM) Food in Britain  

Microsoft Academic Search

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

Alexa Spence; Ellen Townsend

2006-01-01

253

Challenges for methods to detect genetically modified DNA in foods  

Microsoft Academic Search

Qualitative detection methods for genetically modified (GM) DNA sequences in foods have evolved fast during the past years. The sensitivity of these systems is extremely high, even for processed foodstuffs. However, in future, quantitative results about the fraction of GM material in a composite food will be needed and the fast increasing number of GM foods on the market demands

Georg A Schreiber

1999-01-01

254

Biological and biomedical aspects of genetically modified food  

Microsoft Academic Search

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.

Peter Celec; Martina Kuku?ková; Veronika Renczésová; Satheesh Natarajan; Roland Pálffy; Roman Gardlík; Július Hodosy; Michal Behuliak; Barbora Vlková; Gabriel Minárik; Tomáš Szemes; Stanislav Stuchlík; Ján Tur?a

2005-01-01

255

Use of Genetically Modified Viruses and Genetically Engineered Virus-vector Vaccines: Environmental Effects  

Microsoft Academic Search

Despite major therapeutic advances, infectious diseases remain highly problematic. Recent advancements in technology in producing DNA-based vaccines, together with the growing knowledge of the immune system, have provided new insights into the identification of the epitopes needed to target the development of highly targeted vaccines. Genetically modified (GM) viruses and genetically engineered virus-vector vaccines possess significant unpredictability and a number

Vivian S. W. Chan

2006-01-01

256

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

PubMed

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. PMID:17080241

Yonekura-Sakakibara, Keiko; Saito, Kazuki

2006-12-01

257

A practical approach to screen for authorised and unauthorised genetically modified plants.  

PubMed

In routine analysis, screening methods based on real-time PCR are most commonly used for the detection of genetically modified (GM) plant material in food and feed. In this paper, it is shown that the combination of five DNA target sequences can be used as a universal screening approach for at least 81 GM plant events authorised or unauthorised for placing on the market and described in publicly available databases. Except for maize event LY038, soybean events DP-305423 and BPS-CV127-9 and cotton event 281-24-236 x 3006-210-23, at least one of the five genetic elements has been inserted in these GM plants and is targeted by this screening approach. For the detection of these sequences, fully validated real-time PCR methods have been selected. A screening table is presented that describes the presence or absence of the target sequences for most of the listed GM plants. These data have been verified either theoretically according to available databases or experimentally using available reference materials. The screening table will be updated regularly by a network of German enforcement laboratories. PMID:19855963

Waiblinger, Hans-Ulrich; Grohmann, Lutz; Mankertz, Joachim; Engelbert, Dirk; Pietsch, Klaus

2010-03-01

258

Detection of genetically modified DNA sequences in milk from the Italian market.  

PubMed

The possible transfer and accumulation of novel DNA and/or proteins in food for human consumption derived from animals receiving genetically modified (GM) feed is at present the object of scientific dispute. A number of studies failed to identify GM DNA in milk, meat, or eggs derived from livestock receiving GM feed ingredients. The present study was performed in order to: (i) develop a valid protocol by PCR and multicomponent analysis for the detection of specific DNA sequences in milk, focused on GM maize and GM soybean; (ii) assess the stability of transgenic DNA after pasteurization treatment and (iii) determine the presence of GM DNA sequences in milk samples collected from the Italian market. Results from the screening of 60 samples of 12 different milk brands demonstrated the presence of GM maize sequences in 15 (25%) and of GM soybean sequences in 7 samples (11.7%). Our screening methodology shows a very high sensitivity and the use of an automatic identification of the amplified products increases its specificity and reliability. Moreover, we demonstrated that the pasteurization process is not able to degrade the DNA sequences in spiked milk samples. The detection of GM DNA in milk can be interpreted as an indicator of fecal or airborne contamination, respectively, with feed DNA or feed particles, although an alternative source of contamination, possibly recognizable in the natural environment can be suggested. Further studies, performed on a larger number of milk samples, are needed to understand the likely source of contamination of milk collected from the Italian market. PMID:16373205

Agodi, Antonella; Barchitta, Martina; Grillo, Agata; Sciacca, Salvatore

2006-01-01

259

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

PubMed

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. PMID:21296423

Domingo, José L; Giné Bordonaba, Jordi

2011-05-01

260

Water distribution network optimization using a modified genetic algorithm  

NASA Astrophysics Data System (ADS)

A modified genetic algorithm (GA) is proposed for water distribution network optimization. Several changes are introduced in the selection and mutation processes of a simple GA. In each generation a constant number of solutions is eliminated, the selected ones are ranked for crossover, and the new solutions are allowed to undergo at most one mutation. All these modifications greatly increase the algorithm convergence. The modified GA is tested on the New York City water supply expansion problem. It obtains the lowest-cost feasible solution reported in the literature in far fewer generations than any previous GA.

Montesinos, Pilar; Garcia-Guzman, Adela; Ayuso, Jose Luis

1999-11-01

261

Teosinte glume architecture 1: A Genetic Locus Controlling a Key Step in Maize Evolution  

Microsoft Academic Search

Teosinte, the probable progenitor of maize, has kernels that are encased in hardened fruitcases, which interfere with the use of the kernels as food. Although the components of the fruitcase are present in maize, their development is disrupted so that the kernels are not encased as in teosinte but exposed on the ear. The change from encased to exposed kernels

Jane Dorweiler; Adrian Stec; Jerry Kermicle; John Doebley

1993-01-01

262

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

PubMed

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

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

2013-09-01

263

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

ERIC Educational Resources Information Center

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.)

Taylor, Ann T. S.

2004-01-01

264

Genetic diversity among progenitors and elite lines from the Iowa Stiff Stalk Synthetic (BSSS) maize population: comparison of allozyme and RFLP data  

Microsoft Academic Search

Data for restriction fragment length polymorphisms (RFLPs) of 144 clone-enzyme combinations and for 22 allozyme loci from 21 U.S. Corn Belt maize (Zea mays L.) inbreds were analyzed. The genetic materials included 14 progenitors of the Iowa Stiff Stalk Synthetic (BSSS) maize population, both parents of one missing BSSS progenitor, four elite inbreds derived from BSSS, and inbred Mo17. Objectives

M. M. Messmer; A. E. Melchinger; M. Lee; W. L. Woodman; E. A. Lee; K. R. Lamkey

1991-01-01

265

Environmental risk assessment of genetically modified plants - concepts and controversies  

Microsoft Academic Search

Background and purpose  In Europe, the EU Directive 2001\\/18\\/EC lays out the main provisions of environmental risk assessment (ERA) of genetically\\u000a modified (GM) organisms that are interpreted very differently by different stakeholders. The purpose of this paper is to:\\u000a (a) describe the current implementation of ERA of GM plants in the EU and its scientific shortcomings, (b) present an improved\\u000a ERA

Angelika Hilbeck; Matthias Meier; Jörg Römbke; Stephan Jänsch; Hanka Teichmann; Beatrix Tappeser

2011-01-01

266

In vivo characterization of skeletal phenotype of genetically modified mice  

Microsoft Academic Search

Genetically modified mouse models provide an important tool for understanding of the roles of specific gene in skeletal growth,\\u000a development, and aging. Appropriate study design is essential for characterization of skeletal phenotype of these mice. It\\u000a is important to characterize the bone status of the different phases of skeletal development including the early rapid growth,\\u000a attainment of peak bone mass,

Hua Zhu Ke

2005-01-01

267

Molecular toolbox for the identification of unknown genetically modified organisms  

Microsoft Academic Search

Competent laboratories monitor genetically modified organisms (GMOs) and products derived thereof in the food and feed chain\\u000a in the framework of labeling and traceability legislation. In addition, screening is performed to detect the unauthorized\\u000a presence of GMOs including asynchronously authorized GMOs or GMOs that are not officially registered for commercialization\\u000a (unknown GMOs). Currently, unauthorized or unknown events are detected by

Tom Ruttink; Rolinde Demeyer; Elke Van Gulck; Bart Van Droogenbroeck; Maddalena Querci; Isabel Taverniers; Marc De Loose

2010-01-01

268

Environmental risks of chemicals and genetically modified organisms: A comparison  

Microsoft Academic Search

The principles of precaution and sustainability require more consideration in the assessment of environmental risks posed\\u000a by chemicals and genetically modified organisms. Instead of applying risk reduction measures when there are serious indications\\u000a for damage, full scientific certainty is often waited for before taking action. The precautionary principle particularly should\\u000a be applied in those cases in which the extent and

Klaus Günter Steinhäuser

2001-01-01

269

Examining consumer behaviour toward genetically modified (GM) food in Britain  

Microsoft Academic Search

Abstract This study examined,behaviour towards genetically modified (GM) food in a British community-based,sample. We used an equivalent gaintask in which participants actually received the options they chose to encoura ge truthful responding. In conjunction with this, theory of planned behaviour (TPB) components were evaluated so as to examine the relative importance of behavio ural influences in this domain. Here the

Alexa Spence

2006-01-01

270

An oligonucleotide array to detect genetically modified events in potato  

Microsoft Academic Search

For rapid and simultaneous detection of transgenic elements in genetically modified (GM) food crops, we explored DNA array\\u000a technology. Forty-four oligonucleotide 23-to 31-mers were selected to use in an array on the basis of melting temperature\\u000a and sequence specificity. Selected oligonucleotides consisted of DNA fragments corresponding to structural and regulatory\\u000a elements and selectable markers used in developing transgenic crops, such

Malliga M. Nagarajan; Solke H. De Boer

2003-01-01

271

Persistence of Genetically Modified Potatoes in the Field  

Microsoft Academic Search

Volunteers from genetically modified (GM) potatoes may pose an environmental problem if allowed to grow in the field after\\u000a the annual crop is harvested. We tested whether they are more likely to produce volunteers than non-GM potatoes. Specifically,\\u000a we compared the number of volunteers, number of tubers per plant, tuber size, and their vertical distribution in the soil.\\u000a More volunteer

Chang-Gi Kim; Do Young Kim; Ye Seul Moon; Hyo-Jeong Kim; Dae In Kim; Young Jin Chun; Kee Woong Park; Soon Chun Jeong; Soo Young Kim; Hwan Mook Kim

2010-01-01

272

Heterogeneity of genetic modifiers ensures normal cardiac development  

PubMed Central

Background Mutations of the transcription factor Nkx2-5 cause pleiotropic heart defects with incomplete penetrance. This variability suggests that additional factors can affect or prevent the mutant phenotype. We assess here the role of genetic modifiers and their interactions. Methods and Results Heterozygous Nkx2-5 knockout mice in the inbred strain background C57Bl/6 frequently have atrial and ventricular septal defects (ASD, VSD). The incidences are substantially reduced in the Nkx2-5+/? progeny of first generation (F1) outcrosses to the strains FVB/N or A/J. Defects recur in the second generation (F2) of the F1 × F1 intercross or backcrosses to the parental strains. Analysis of >3000 Nkx2-5+/? hearts from five F2 crosses demonstrates the profound influence of genetic modifiers on disease presentation. Based upon their incidences and co-incidences, anatomically distinct malformations have shared and unique modifiers. All three strains carry susceptibility alleles at different loci for ASD and VSD. Relative to the other two strains, A/J carries polymorphisms that confer greater susceptibility to ASD and atrioventricular septal defects, and C57Bl/6 to muscular VSD. Segregation analyses reveal that two or more loci influence membranous VSD susceptibility, whereas three or more loci and at least one epistatic interaction affect muscular VSD and ASD. Conclusion Alleles of modifier genes can either buffer perturbations on cardiac development or direct the manifestation of a defect. In a genetically heterogeneous population the predominant effect of modifier genes is health.

Winston, Julia B.; Erlich, Jonathan M.; Green, Courtney A.; Aluko, Ashley; Kaiser, Kristine A.; Takematsu, Mai; Barlow, Robert S.; Sureka, Ashish O.; LaPage, Martin J.; Janss, Luc L.; Jay, Patrick Y.

2010-01-01

273

The Detection of Genetically Modified Organisms: An Overview  

NASA Astrophysics Data System (ADS)

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).

Ovesná, Jaroslava; Demnerová, Kate?ina; Pouchová, Vladimíra

274

Irradiation influence on the detection of genetic-modified soybeans  

NASA Astrophysics Data System (ADS)

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.

Villavicencio, A. L. C. H.; Araújo, M. M.; Baldasso, J. G.; Aquino, S.; Konietzny, U.; Greiner, R.

2004-09-01

275

Maize Centromeres: Organization and Functional Adaptation in the Genetic Background of Oat  

PubMed Central

Centromeric DNA sequences in multicellular eukaryotes are often highly repetitive and are not unique to a specific centromere or to centromeres at all. Thus, it is a major challenge to study the fine structure of individual plant centromeres. We used a DNA fiber-fluorescence in situ hybridization approach to study individual maize (Zea mays) centromeres using oat (Avena sativa)-maize chromosome addition lines. The maize centromere-specific satellite repeat CentC in the addition lines allowed us to delineate the size and organization of centromeric DNA of individual maize chromosomes. We demonstrate that the cores of maize centromeres contain mainly CentC arrays and clusters of a centromere-specific retrotransposon, CRM. CentC and CRM sequences are highly intermingled. The amount of CentC/CRM sequence varies from ?300 to >2800 kb among different centromeres. The association of CentC and CRM with centromeric histone H3 (CENH3) was visualized by a sequential detection procedure on stretched centromeres. The analysis revealed that CENH3 is always associated with CentC and CRM but that not all CentC or CRM sequences are associated with CENH3. We further demonstrate that in the chromosomal addition lines in which two CenH3 genes were present, one from oat and one from maize, the oat CENH3 was consistently incorporated by the maize centromeres.

Jin, Weiwei; Melo, Juliana R.; Nagaki, Kiyotaka; Talbert, Paul B.; Henikoff, Steven; Dawe, R. Kelly; Jiang, Jiming

2004-01-01

276

Genetically modified yeast species, and fermentation processes using genetically modified yeast  

SciTech Connect

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.

Rajgarhia, Vineet; Koivuranta, Kari; Penttila, Merja; Ilmen, Marja; Suominen, Pirkko; Aristidou, Aristos; Miller, Christopher Kenneth; Olson, Stacey; Ruohonen, Laura

2013-05-14

277

Genetically modified yeast species and fermentation processes using genetically modified yeast  

SciTech Connect

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.

Rajgarhia, Vineet (Kingsport, TN); Koivuranta, Kari (Helsinki, FI); Penttila, Merja (Helsinki, FI); Ilmen, Marja (Helsinki, FI); Suominen, Pirkko (Maple Grove, MN); Aristidou, Aristos (Maple Grove, MN); Miller, Christopher Kenneth (Cottage Grove, MN); Olson, Stacey (St. Bonifacius, MN); Ruohonen, Laura (Helsinki, FI)

2011-05-17

278

Impact of genetics and environment on the metabolite composition of maize grain.  

PubMed

This study sought to assess genetic and environmental impacts on the metabolite composition of maize grain. Gas chromatography coupled to time-of-flight mass spectrometry (GC-TOF-MS) measured 119 identified metabolites including free amino acids, free fatty acids, sugars, organic acids, and other small molecules in a range of hybrids derived from 48 inbred lines crossed against two different tester lines (from the C103 and Iodent heterotic groups) and grown at three locations in Iowa. It was reasoned that expanded metabolite coverage would contribute to a comprehensive evaluation of the grain metabolome, its degree of variability, and, in principle, its relationship to other compositional and agronomic features. The metabolic profiling results established that the small molecule metabolite pool is highly dependent on genotypic variation and that levels of certain metabolite classes may have an inverse genotypic relationship to each other. Different metabolic phenotypes were clearly associated with the two distinct tester populations. Overall, grain from the C103 lines contained higher levels of free fatty acids and organic acids, whereas grain from the Iodent lines were associated with higher levels of amino acids and carbohydrates. In addition, the fold-range of genotype mean values [composed of six samples each (two tester crosses per inbred x three field sites)] for identified metabolites ranged from approximately 1.5- to 93-fold. Interestingly, some grain metabolites showed a non-normal distribution over the entire corn population, which could, at least in part, be attributed to large differences in metabolite values within specific inbred crosses relative to other inbred sets. This study suggests a potential role for metabolic profiling in assisting the process of selecting elite germplasm in biotechnology development, or marker-assisted breeding. PMID:20158212

Skogerson, Kirsten; Harrigan, George G; Reynolds, Tracey L; Halls, Steven C; Ruebelt, Martin; Iandolino, Alberto; Pandravada, Anand; Glenn, Kevin C; Fiehn, Oliver

2010-03-24

279

Phylogeography and population genetics of the maize stalk borer Busseola fusca (Lepidoptera, Noctuidae) in sub-Saharan Africa.  

PubMed

The population genetics and phylogeography of African phytophagous insects have received little attention. Some, such as the maize stalk borer Busseola fusca, display significant geographic differences in ecological preferences that may be congruent with patterns of molecular variation. To test this, we collected 307 individuals of this species from maize and cultivated sorghum at 52 localities in West, Central and East Africa during the growing season. For all collected individuals, we sequenced a fragment of the mitochondrial cytochrome b. We tested hypotheses concerning the history and demographic structure of this species. Phylogenetic analyses and nested clade phylogeographic analyses (NCPA) separated the populations into three mitochondrial clades, one from West Africa, and two--Kenya I and Kenya II--from East and Central Africa. The similar nucleotide divergence between clades and nucleotide diversity within clades suggest that they became isolated at about the same time in three different refuges in sub-Saharan Africa and have similar demographic histories. The results of mismatch distribution analyses were consistent with the demographic expansion of these clades. Analysis of molecular variance (amova) indicated a high level of geographic differentiation at different hierarchical levels. NCPA suggested that the observed distribution of haplotypes at several hierarchical levels within the three major clades is best accounted for by restricted gene flow with isolation by distance. The domestication of sorghum and the introduction of maize in Africa had no visible effect on the geographic patterns observed in the B. fusca mitochondrial genome. PMID:16448409

Sezonlin, M; Dupas, S; Le Rü, B; Le Gall, P; Moyal, P; Calatayud, P-A; Giffard, I; Faure, N; Silvain, J-F

2006-02-01

280

[Genetically modified organisms: a new threat to food safety].  

PubMed

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. PMID:15913060

Spendeler, Liliane

2005-01-01

281

Comparative diversity of arthropods on Bt maize and non-Bt maize in two different cropping systems in South Africa.  

PubMed

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. PMID:24472209

Truter, J; Van Hamburg, H; Van Den Berg, J

2014-02-01

282

A pair of homoeolog ClpP5 genes underlies a virescent yellow-like mutant and its modifier in maize.  

PubMed

Gene-background interaction is a commonly observed phenomenon in many species, but the molecular mechanisms of such an interaction is less well understood. Here we report the cloning of a maize mutant gene and its modifier. A recessive mutant with a virescent yellow-like (vyl) phenotype was identified in an ethyl methanesulfonate-mutagenized population derived from the maize inbred line B73. Homozygous mutant maize plants exhibited a yellow leaf phenotype after emergence but gradually recovered and became indistinguishable from wild-type plants after approximately 2 weeks. Taking the positional cloning approach, the Chr.9_ClpP5 gene, one of the proteolytic subunits of the chloroplast Clp protease complex, was identified and validated as the candidate gene for vyl. When introgressed by backcross into the maize inbred line PH09B, the mutant phenotype of vyl lasted much longer in the greenhouse and was lethal in the field, implying the presence of a modifier(s) for vyl. A major modifier locus was identified on chromosome 1, and a paralogous ClpP5 gene was isolated and confirmed as the candidate for the vyl-modifier. Expression of Chr.1_ClpP5 is induced significantly in B73 by the vyl mutation, while the expression of Chr.1_ClpP5 in PH09B is not responsive to the vyl mutation. Moreover, expression and sequence analysis suggests that the PH09B Chr.1_ClpP5 allele is functionally weaker than the B73 allele. We propose that functional redundancy between duplicated paralogous genes is the molecular mechanism for the interaction between vyl and its modifier. PMID:24888539

Xing, Anqi; Williams, Mark E; Bourett, Timothy M; Hu, Wangnan; Hou, Zhenglin; Meeley, Robert B; Jaqueth, Jennifer; Dam, Thao; Li, Bailin

2014-07-01

283

The global income and production effects of genetically modified (GM) crops 1996-2011.  

PubMed

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. PMID:23549349

Brookes, Graham; Barfoot, Peter

2013-01-01

284

Detection of processed genetically modified food using CIM monolithic columns for DNA isolation.  

PubMed

The availability of sufficient quantities of DNA of adequate quality is crucial in polymerase chain reaction (PCR)-based methods for genetically modified food detection. In this work, the suitability of anion-exchange CIM (Convective Interaction Media; BIA Separations, Ljubljana, Slovenia) monolithic columns for isolation of DNA from food was studied. Maize and its derivates corn meal and thermally pretreated corn meal were chosen as model food. Two commercially available CIM disk columns were tested: DEAE (diethylaminoethyl) and QA (quaternary amine). Preliminary separations were performed with standard solution of salmon DNA at different pH values and different NaCl concentrations in mobile phase. DEAE groups and pH 8 were chosen for further isolations of DNA from a complex matrix-food extract. The quality and quantity of isolated DNA were tested on agarose gel electrophoresis, with UV-scanning spectrophotometry, and by amplification with real-time PCR. DNA isolated in this way was of suitable quality for further PCR analyses. The described method is also applicable for DNA isolation from processed foods with decreased DNA content. Furthermore, it is more effective and less time-consuming in comparison with the existing proposed methods for isolation of DNA from plant-derived foods. PMID:15782956

Jerman, Sergej; Podgornik, Ales; Cankar, Katarina; Cadet, Neza; Skrt, Mihaela; Zel, Jana; Raspor, Peter

2005-02-11

285

Multitarget Real-Time PCR-Based System: Monitoring for Unauthorized Genetically Modified Events in India.  

PubMed

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. PMID:24971889

Randhawa, Gurinder Jit; Singh, Monika; Sood, Payal; Bhoge, Rajesh K

2014-07-23

286

Genetic and biochemical differences in populations bred for extremes in maize grain methionine concentration  

PubMed Central

Background Methionine is an important nutrient in animal feed and several approaches have been developed to increase methionine concentration in maize (Zea mays L.) grain. One approach is through traditional breeding using recurrent selection. Using divergent selection, genetically related populations with extreme differences in grain methionine content were produced. In order to better understand the molecular mechanisms controlling grain methionine content, we examined seed proteins, transcript levels of candidate genes, and genotypes of these populations. Results Two populations were selected for high or low methionine concentration for eight generations and 40 and 56% differences between the high and low populations in grain methionine concentration were observed. Mean values between the high and low methionine populations differed by greater than 1.5 standard deviations in some cycles of selection. Other amino acids and total protein concentration exhibited much smaller changes. In an effort to understand the molecular mechanisms that contribute to these differences, we compared transcript levels of candidate genes encoding high methionine seed storage proteins involved in sulfur assimilation or methionine biosynthesis. In combination, we also explored the genetic mechanisms at the SNP level through implementation of an association analysis. Significant differences in methionine-rich seed storage protein genes were observed in comparisons of high and low methionine populations, while transcripts of seed storage proteins lacking high levels of methionine were unchanged. Seed storage protein levels were consistent with transcript levels. Two genes involved in sulfur assimilation, Cys2 and CgS1 showed substantial differences in allele frequencies when two selected populations were compared to the starting populations. Major genes identified across cycles of selection by a high-stringency association analysis included dzs18, wx, dzs10, and zp27. Conclusions We hypothesize that transcriptional changes alter sink strength by altering the levels of methionine-rich seed storage proteins. To meet the altered need for sulfur, a cysteine-rich seed storage protein is altered while sulfur assimilation and methionine biosynthesis throughput is changed by selection for certain alleles of Cys2 and CgS1.

2014-01-01

287

A 90-day toxicology study of transgenic lysine-rich maize grain (Y642) in Sprague-Dawley rats.  

PubMed

The gene for a lysine-rich protein (sb401) obtained from potatoes (Solanum berthaultii) was inserted into maize seed to produce Y642 transgenic maize. Compositional analysis of Y642 grain demonstrated that the concentrations of lysine and total protein were higher than those observed in maize grain from a near-isogenic non-genetically modified (non-GM) commercially available control quality protein maize (Nongda 108). The safety of Y642 maize grain was assessed by comparison of toxicology response variables in Sprague-Dawley (SD) rats consuming diets containing Y642 maize grain with those containing Nongda 108 maize grain. Maize grains from Y642 or Nongda 108 were incorporated into rodent diets at low (30%) or high concentrations (76%) and administered to SD rats (n=10/sex/group) for 90 days. An additional group of negative control group of rats (n=10/sex/group) were fed AIN93G diets. No adverse diet-related differences in body weights, feed consumption/utilization, clinical chemistry, hematology, absolute and relative organ weights were observed. Further, no differences in gross or microscopic pathology were observed between rats consuming diets with Y642 maize grain compared with rats consuming diets containing Nongda 108 maize grain. These results demonstrated that Y642 lysine-rich maize is as safe and nutritious as conventional quality protein maize. PMID:19073230

He, Xiao Yun; Tang, Mao Zhi; Luo, Yun Bo; Li, Xin; Cao, Si Shuo; Yu, Jing Juan; Delaney, Bryan; Huang, Kun Lun

2009-02-01

288

Benefits and risks associated with genetically modified food products.  

PubMed

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. PMID:24069841

Kramkowska, Marta; Grzelak, Teresa; Czy?ewska, Krystyna

2013-01-01

289

Safety assessment of genetically modified plants with deliberately altered composition.  

PubMed

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

Halford, Nigel G; Hudson, Elizabeth; Gimson, Amy; Weightman, Richard; Shewry, Peter R; Tompkins, Steven

2014-08-01

290

Information system for monitoring environmental impacts of genetically modified organisms  

Microsoft Academic Search

Background, aim and scope  European legislation stipulates that genetically modified organisms (GMO) have to be monitored to identify potential adverse\\u000a environmental effects. A wealth of different types of monitoring data from various sources including existing environmental\\u000a monitoring programmes is expected to accumulate. This requires an information system to efficiently structure, process and\\u000a evaluate the monitoring data.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  A structure for an Information

Hauke Reuter; Ulrike Middelhoff; Frieder Graef; Richard Verhoeven; Thomas Batz; Martin Weis; Gunther Schmidt; Winfried Schröder; Broder Breckling

2010-01-01

291

Plant potassium content modifies the effects of arbuscular mycorrhizal symbiosis on root hydraulic properties in maize plants.  

PubMed

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. PMID:22370879

El-Mesbahi, Mohamed Najib; Azcón, Rosario; Ruiz-Lozano, Juan Manuel; Aroca, Ricardo

2012-10-01

292

Isothermal amplification of genetically modified DNA sequences directly from plant tissues lowers the barriers to high-throughput and field-based genotyping.  

PubMed

DNA extractions are a major cost for high-throughput genotyping. The loop-mediated isothermal amplification (LAMP) assay has been used for the detection of two genetically modified (GM) related sequences. The amplification of target DNA sequences from leaf and maize seed tissues prepared with minimum preparative treatment (disruption in water) demonstrates the ability of LAMP to work in conditions normally inhibitive to PCRs. The wide dynamic range of detection in these samples suggests that LAMP is highly sensitive even when the target is presented in such a crude form. LAMP offers a means of reducing genotyping costs as well as simplifying testing procedures. PMID:19772345

Lee, David; La Mura, Maurizio; Allnutt, Theo; Powell, Wayne; Greenland, Andy

2009-10-28

293

Genetic Architecture of Flowering Time in Maize As Inferred From Quantitative Trait Loci Meta-analysis and Synteny Conservation With the Rice Genome  

PubMed Central

Genetic architecture of flowering time in maize was addressed by synthesizing a total of 313 quantitative trait loci (QTL) available for this trait. These were analyzed first with an overview statistic that highlighted regions of key importance and then with a meta-analysis method that yielded a synthetic genetic model with 62 consensus QTL. Six of these displayed a major effect. Meta-analysis led in this case to a twofold increase in the precision in QTL position estimation, when compared to the most precise initial QTL position within the corresponding region. The 62 consensus QTL were compared first to the positions of the few flowering-time candidate genes that have been mapped in maize. We then projected rice candidate genes onto the maize genome using a synteny conservation approach based on comparative mapping between the maize genetic map and japonica rice physical map. This yielded 19 associations between maize QTL and genes involved in flowering time in rice and in Arabidopsis. Results suggest that the combination of meta-analysis within a species of interest and synteny-based projections from a related model plant can be an efficient strategy for identifying new candidate genes for trait variation.

Chardon, Fabien; Virlon, Berangere; Moreau, Laurence; Falque, Matthieu; Joets, Johann; Decousset, Laurent; Murigneux, Alain; Charcosset, Alain

2004-01-01

294

Detection and quantification of genetically modified organisms using very short, locked nucleic acid TaqMan probes.  

PubMed

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. PMID:18494480

Salvi, Sergio; D'Orso, Fabio; Morelli, Giorgio

2008-06-25

295

Weed seed resources for birds in fields with contrasting conventional and genetically modified herbicide-tolerant crops  

PubMed Central

The UK Farm Scale Evaluations (FSEs) have shown that the use of broad spectrum herbicides on genetically modified herbicide-tolerant (GMHT) crops can have dramatic effects on weed seed production compared to management of conventional varieties. Here, we use FSE data and information on bird diets to determine how GMHT cropping might change the food resources available to farmland birds. More than 60 fields of each of four crops, spring- and winter-sown oilseed rape, beet and maize, were split, one half being sown with a conventional variety, the other with a GMHT variety. Seed rain from weeds known to be important in the diets of 17 granivorous farmland bird species was measured under the two treatments. In beet and spring oilseed rape, rain of weed seeds important in the diets of 16 bird species was significantly reduced in GMHT compared to conventional halves; for no species did it increase. In winter oilseed rape, rain of weed seeds important in the diets of 10 species was significantly reduced in GMHT halves; for only one species did it increase significantly. By contrast, in maize, rain of weed seeds important in the diets of seven species was significantly greater in GMHT halves; for no species was it reduced. Treatment effects for the total weed seed energy available to each bird species were very similar to those for seed rain alone. Measuring the effects on individual bird species was outside the scope of this study. Despite this, these results suggest that should beet, spring and winter rape crops in the UK be largely replaced by GMHT varieties and managed as in the FSEs, this would markedly reduce important food resources for farmland birds, many of which declined during the last quarter of the twentieth century. By contrast, GMHT maize would be beneficial to farmland birds.

Gibbons, David W; Bohan, David A; Rothery, Peter; Stuart, Rick C; Haughton, Alison J; Scott, Rod J; Wilson, Jeremy D; Perry, Joe N; Clark, Suzanne J; Dawson, Robert J.G; Firbank, Les G

2006-01-01

296

Genetically modified T lymphocytes: more than just direct effectors.  

PubMed

Evaluation of: Russo V, Pilla L, Lunghi F et al. Clinical and immunologic responses in melanoma patients vaccinated with MAGE-A3-genetically modified lymphocytes. Int. J. Cancer 132(11), 2557-2566 (2012). When one mentions T lymphocytes, one easily recognizes the effective and antigen-specific manner by which T lymphocytes execute cellular immune responses towards pathogen-infected or cancerous cells. Russo and coworkers recognized the other side of the coin and exploited the potency of T cells to act as a cellular vaccine, to which end they used T cells transduced with the cancer-testis antigen MAGE-A3. Twenty-three patients with MAGE-A3-expressing melanoma were treated and six patients developed MAGE-A3-specific immune responses and showed clinical benefit, whereas patients without a MAGE-A3-specific immune response did not show clinical benefit. This report includes and extends on results from a pilot study including ten patients, of which three developed MAGE-A3-specific immune responses. The present study further explores a potential beneficial application of the observed immunogenicity of genetically modified T cells. PMID:23829619

Lamers, Cor H J; Debets, Reno

2013-07-01

297

Mucosal vaccination and therapy with genetically modified lactic acid bacteria.  

PubMed

Lactic acid bacteria (LAB) have proved to be effective mucosal delivery vehicles that overcome the problem of delivering functional proteins to the mucosal tissues. By the intranasal route, both live and killed LAB vaccine strains have been shown to elicit mucosal and systemic immune responses that afford protection against infectious challenges. To be effective via oral administration, frequent dosing over several weeks is required but new targeting and adjuvant strategies have clearly demonstrated the potential to increase the immunogenicity and protective immunity of LAB vaccines. Oral administration of Lactococcus lactis has been shown to induce antigen-specific oral tolerance (OT) to secreted recombinant antigens. LAB delivery is more efficient at inducing OT than the purified antigen, thus avoiding the need for purification of large quantities of antigen. This approach holds promise for new therapeutic interventions in allergies and antigen-induced autoimmune diseases. Several clinical and research reports demonstrate considerable progress in the application of genetically modified L. lactis for the treatment of inflammatory bowel disease (IBD). New medical targets are on the horizon, and the approval by several health authorities and biosafety committees of a containment system for a genetically modified L. lactis that secretes Il-10 should pave the way for new LAB delivery applications in the future. PMID:22129390

Wells, Jerry

2011-01-01

298

Electrospun fiber membranes enable proliferation of genetically modified cells  

PubMed Central

Polycaprolactone (PCL) and its blended composites (chitosan, gelatin, and lecithin) are well-established biomaterials that can enrich cell growth and enable tissue engineering. However, their application in the recovery and proliferation of genetically modified cells has not been studied. In the study reported here, we fabricated PCL-biomaterial blended fiber membranes, characterized them using physicochemical techniques, and used them as templates for the growth of genetically modified HCT116-19 colon cancer cells. Our data show that the blended polymers are highly miscible and form homogenous electrospun fiber membranes of uniform texture. The aligned PCL nanofibers support robust cell growth, yielding a 2.5-fold higher proliferation rate than cells plated on standard plastic plate surfaces. PCL-lecithin fiber membranes yielded a 2.7-fold higher rate of proliferation, while PCL-chitosan supported a more modest growth rate (1.5-fold higher). Surprisingly, PCL-gelatin did not enhance cell proliferation when compared to the rate of cell growth on plastic surfaces.

Borjigin, Mandula; Eskridge, Chris; Niamat, Rohina; Strouse, Bryan; Bialk, Pawel; Kmiec, Eric B

2013-01-01

299

Electrospun fiber membranes enable proliferation of genetically modified cells.  

PubMed

Polycaprolactone (PCL) and its blended composites (chitosan, gelatin, and lecithin) are well-established biomaterials that can enrich cell growth and enable tissue engineering. However, their application in the recovery and proliferation of genetically modified cells has not been studied. In the study reported here, we fabricated PCL-biomaterial blended fiber membranes, characterized them using physicochemical techniques, and used them as templates for the growth of genetically modified HCT116-19 colon cancer cells. Our data show that the blended polymers are highly miscible and form homogenous electrospun fiber membranes of uniform texture. The aligned PCL nanofibers support robust cell growth, yielding a 2.5-fold higher proliferation rate than cells plated on standard plastic plate surfaces. PCL-lecithin fiber membranes yielded a 2.7-fold higher rate of proliferation, while PCL-chitosan supported a more modest growth rate (1.5-fold higher). Surprisingly, PCL-gelatin did not enhance cell proliferation when compared to the rate of cell growth on plastic surfaces. PMID:23467983

Borjigin, Mandula; Eskridge, Chris; Niamat, Rohina; Strouse, Bryan; Bialk, Pawel; Kmiec, Eric B

2013-01-01

300

Region-specific cis- and trans-acting factors contribute to genetic variability in meiotic recombination in maize.  

PubMed

Understanding the genetic basis for variability in recombination rates is important for general genetic studies and plant-breeding efforts. Earlier studies had suggested increased recombination frequencies in particular F2 populations derived from the maize inbred A188. A detailed phenotypic and molecular analysis was undertaken to extend these observations and dissect the responsible factors. A heritable increase in recombination in the sh1-bz1 interval was observed in these populations. A factor causing an approximate twofold increase mapped to the A188 sh1-Bz1 region, behaved as a dominant, cis-acting factor, affected recombination equally in male and female sporogenesis and did not reduce the well-studied complete interference in the adjacent bz1-wx interval. This factor also did not increase recombination frequencies in the c1-sh1 and bz1-wx intervals, demonstrating independent control of recombination in adjacent intervals. Additional phenotypic analysis of recombination in the c1-sh1 and bz1-wx intervals and RFLP analysis of recombination along chromosomes 7 and 5 suggested that heritable factors controlling recombination in these intervals act largely independently and in trans. Our results show that recombination in these populations, and possibly maize in general, is controlled by both cis- and trans-acting factors that affect specific chromosomal regions. PMID:9215911

Timmermans, M C; Das, O P; Bradeen, J M; Messing, J

1997-07-01

301

The extended auricle1 (eta1) gene is essential for the genetic network controlling postinitiation maize leaf development.  

PubMed Central

The maize leaf is composed of distinct regions with clear morphological boundaries. The ligule and auricle mark the boundary between distal blade and proximal sheath and are amenable to genetic study due to the array of mutants that affect their formation without severely affecting viability. Herein, we describe the novel maize gene extended auricle1 (eta1), which is essential for proper formation of the blade/sheath boundary. Homozygous eta1 individuals have a wavy overgrowth of auricle tissue and the blade/sheath boundary is diffuse. Double-mutant combinations of eta1 with genes in the knox and liguleless pathways result in synergistic and, in some cases, dosage-dependent interactions. While the phenotype of eta1 mutant individuals resembles that of dominant knox overexpression phenotypes, eta1 mutant leaves do not ectopically express knox genes. In addition, eta1 interacts synergistically with lg1 and lg2, but does not directly affect the transcription of either gene in leaf primordia. We present evidence based on genetic and molecular analyses that eta1 provides a downstream link between the knox and liguleless pathways.

Osmont, Karen S; Jesaitis, Lynne A; Freeling, Michael

2003-01-01

302

Mapping Quantitative Trait Loci Using Naturally Occurring Genetic Variance Among Commercial Inbred Lines of Maize (Zea mays L.)  

PubMed Central

Many commercial inbred lines are available in crops. A large amount of genetic variation is preserved among these lines. The genealogical history of the inbred lines is usually well documented. However, quantitative trait loci (QTL) responsible for the genetic variances among the lines are largely unexplored due to lack of statistical methods. In this study, we show that the pedigree information of the lines along with the trait values and marker information can be used to map QTL without the need of further crossing experiments. We develop a Monte Carlo method to estimate locus-specific identity-by-descent (IBD) matrices. These IBD matrices are further incorporated into a mixed-model equation for variance component analysis. QTL variance is estimated and tested at every putative position of the genome. The actual QTL are detected by scanning the entire genome. Applying this new method to a well-documented pedigree of maize (Zea mays L.) that consists of 404 inbred lines, we mapped eight QTL for the maize male flowering trait, growing degree day heat units to pollen shedding (GDUSHD). These detected QTL contributed >80% of the variance observed among the inbred lines. The QTL were then used to evaluate all the inbred lines using the best linear unbiased prediction (BLUP) technique. Superior lines were selected according to the estimated QTL allelic values, a technique called marker-assisted selection (MAS). The MAS procedure implemented via BLUP may be routinely used by breeders to select superior lines and line combinations for development of new cultivars.

Zhang, Yuan-Ming; Mao, Yongcai; Xie, Chongqing; Smith, Howie; Luo, Lang; Xu, Shizhong

2005-01-01

303

Region-Specific Cis- and Trans-Acting Factors Contribute to Genetic Variability in Meiotic Recombination in Maize  

PubMed Central

Understanding the genetic basis for variability in recombination rates is important for general genetic studies and plant-breeding efforts. Earlier studies had suggested increased recombination frequencies in particular F(2) populations derived from the maize inbred A188. A detailed phenotypic and molecular analysis was undertaken to extend these observations and dissect the responsible factors. A heritable increase in recombination in the sh1-bz1 interval was observed in these populations. A factor causing an approximate twofold increase mapped to the A188 Sh1-Bz1 region, behaved as a dominant, cis-acting factor, affected recombination equally in male and female sporogenesis and did not reduce the wellstudied complete interference in the adjacent bz1-wx interval. This factor also did not increase recombination frequencies in the c1-sh1 and bz1-wx intervals, demonstrating independent control of recombination in adjacent intervals. Additional phenotypic analysis of recombination in the c1-sh1 and bz1-wx intervals and RFLP analysis of recombination along chromosomes 7 and 5 suggested that heritable factors controlling recombination in these intervals act largely independently and in trans. Our results show that recombination in these populations, and possibly maize in general, is controlled by both cis- and transacting factors that affect specific chromosomal regions.

Timmermans, MCP.; Das, O. P.; Bradeen, J. M.; Messing, J.

1997-01-01

304

Natural Genetic Variation in Lycopene Epsilon Cyclase Tapped for Maize Biofortification  

PubMed Central

Dietary vitamin A deficiency causes eye disease in 40 million children each year and places 140 to 250 million at risk for health disorders. Many children in sub-Saharan Africa subsist on maize-based diets. Maize displays considerable natural variation for carotenoid composition, including vitamin A precursors ?-carotene, ?-carotene, and ?-cryptoxanthin. Through association analysis, linkage mapping, expression analysis, and mutagenesis, we show that variation at the lycopene epsilon cyclase (lcyE) locus alters flux down ?-carotene versus ?-carotene branches of the carotenoid pathway. Four natural lcyE polymorphisms explained 58% of the variation in these two branches and a threefold difference in provitamin A compounds. Selection of favorable lcyE alleles with inexpensive molecular markers will now enable developing-country breeders to more effectively produce maize grain with higher provitamin A levels.

Harjes, Carlos E.; Rocheford, Torbert R.; Bai, Ling; Brutnell, Thomas P.; Kandianis, Catherine Bermudez; Sowinski, Stephen G.; Stapleton, Ann E.; Vallabhaneni, Ratnakar; Williams, Mark; Wurtzel, Eleanore T.; Yan, Jianbing; Buckler, Edward S.

2010-01-01

305

[Current approaches to the evaluation of genetically modified food products. Soybean 40-3-2 data].  

PubMed

Different methodological approaches were elaborated to evaluate quality and safety of genetically modified food products. The new engineering is proposed to rate medical, biological, genetic and technological advantage of these products. Using the same engineering, a complete analysis of the genetically modified soybean 40-3-2 ("Monsanto Co", USA) has been performed. PMID:10641272

Onishchenko, G G; Tutel'ian, V A; Petukhov, A I; Korolev, A A; Aksiuk, I N; Sorokina, E Iu

1999-01-01

306

Genetic modifiers of nutritional status in cystic fibrosis1234  

PubMed Central

Background: Improved nutrition early in life is associated with better pulmonary function for patients with cystic fibrosis (CF). However, nutritional status is poorly correlated with the CFTR genotype. Objective: We investigated the extent to which modifier genes influence nutrition in children with CF. Design: BMI data were longitudinally collected from the CF Twin-Sibling Study and Cystic Fibrosis Foundation Patient Registry for twins and siblings from 2000 to 2010. A nutritional phenotype was derived for 1124 subjects by calculating the average BMI z score from 5–10 y of age (BMI-z5to10). The genetic contribution to the variation in BMI-z5to10 (ie, heritability) was estimated by comparing the similarity of the phenotype in monozygous twins to that in dizygous twins and siblings. Linkage analysis identified potential modifier-gene loci. Results: The median BMI-z5to10 was ?0.07 (range: ?3.89 to 2.30), which corresponded to the 47th CDC percentile. BMI-z5to10 was negatively correlated with pancreatic insufficiency, history of meconium ileus, and female sex but positively correlated with later birth cohorts and lung function. Monozygous twins showed greater concordance for BMI-z5to10 than did dizygous twins and siblings; heritability estimates from same-sex twin-only analyses ranged from 0.54 to 0.82. For 1010 subjects with pancreatic insufficiency, genome-wide significant linkage was identified on chromosomes 1p36.1 [log of odds (LOD): 5.3] and 5q14 (LOD: 5.1). These loci explained ?16% and ?15%, respectively, of the BMI variance. Conclusions: The analysis of twins and siblings with CF indicates a prominent role for genes other than CFTR to BMI variation. Specifically, regions on chromosomes 1 and 5 appear to harbor genetic modifiers of substantial effect.

Bradley, Gia M; Blackman, Scott M; Watson, Christopher P; Doshi, Vishal K; Cutting, Garry R

2012-01-01

307

In vivo osteoarthritis target validation utilizing genetically-modified mice.  

PubMed

Osteoarthritis (OA) is a progressive disease of cartilage degradation that significantly impacts quality of life. There are currently no effective treatments and, while a large number of potential therapeutic targets exist, most have not been validated in vivo. The range of OA models in the mouse has dramatically expanded in the last decade, beyond spontaneous models, to include genetically modified transgenic, knockout (KO) and knock-in (KI) mice that can develop premature cartilage degeneration reminiscent of OA. In addition, instability models of OA, either induced by intra-articular (IA) collagenase or surgery, are providing a set of tools to assist in the identification of disease-modifying OA drug (DMOAD) targets. These models are now vital tools to dissect the pathways essential to the pathogenesis of OA. Two targets, ADAMTS (a disintegrin and metalloproteinase with thrombospondin-like motifs)-5 and IL-1beta (interleukin-1 beta), have been validated in the surgical destabilization of the medial meniscus model (DMM) in KO mice. Other potential targets evaluated in instability models, either showed no disease modification or a worsening of disease, suggesting that those targets have no role, a protective role or that other, more destructive enzymes etc., can overcompensate. Development of small molecule or protein antagonist inhibitors of therapeutic targets require many years to bring to clinical trials and often confront potency and safety issues which impede successful progress. Validation, or confirmation of therapeutic targets in vivo is most clearly and efficiently obtained by using KO studies, than by creating potent and selective DMOADs to multiple potential targets. While the results in the mouse will not always transpose to the human condition, the track record of mouse knockouts corresponding to the human phenotype have been excellent. These results indicate that the evaluation of genetically modified mice will become increasingly important as we unravel the genes contributing to OA. PMID:17305514

Glasson, Sonya S

2007-02-01

308

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

Microsoft Academic Search

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

W. K Novak; A. G Haslberger

2000-01-01

309

Proliferation of Genetically Modified Human Cells on Electrospun Nanofiber Scaffolds  

PubMed Central

Gene editing is a process by which single base mutations can be corrected, in the context of the chromosome, using single-stranded oligodeoxynucleotides (ssODNs). The survival and proliferation of the corrected cells bearing modified genes, however, are impeded by a phenomenon known as reduced proliferation phenotype (RPP); this is a barrier to practical implementation. To overcome the RPP problem, we utilized nanofiber scaffolds as templates on which modified cells were allowed to recover, grow, and expand after gene editing. Here, we present evidence that some HCT116-19, bearing an integrated, mutated enhanced green fluorescent protein (eGFP) gene and corrected by gene editing, proliferate on polylysine or fibronectin-coated polycaprolactone (PCL) nanofiber scaffolds. In contrast, no cells from the same reaction protocol plated on both regular dish surfaces and polylysine (or fibronectin)-coated dish surfaces proliferate. Therefore, growing genetically modified (edited) cells on electrospun nanofiber scaffolds promotes the reversal of the RPP and increases the potential of gene editing as an ex vivo gene therapy application.

Borjigin, Mandula; Strouse, Bryan; Niamat, Rohina A; Bialk, Pawel; Eskridge, Chris; Xie, Jingwei; Kmiec, Eric B

2012-01-01

310

Proliferation of genetically modified human cells on electrospun nanofiber scaffolds.  

PubMed

Gene editing is a process by which single base mutations can be corrected, in the context of the chromosome, using single-stranded oligodeoxynucleotides (ssODNs). The survival and proliferation of the corrected cells bearing modified genes, however, are impeded by a phenomenon known as reduced proliferation phenotype (RPP); this is a barrier to practical implementation. To overcome the RPP problem, we utilized nanofiber scaffolds as templates on which modified cells were allowed to recover, grow, and expand after gene editing. Here, we present evidence that some HCT116-19, bearing an integrated, mutated enhanced green fluorescent protein (eGFP) gene and corrected by gene editing, proliferate on polylysine or fibronectin-coated polycaprolactone (PCL) nanofiber scaffolds. In contrast, no cells from the same reaction protocol plated on both regular dish surfaces and polylysine (or fibronectin)-coated dish surfaces proliferate. Therefore, growing genetically modified (edited) cells on electrospun nanofiber scaffolds promotes the reversal of the RPP and increases the potential of gene editing as an ex vivo gene therapy application.Molecular Therapy - Nucleic Acids (2012) 1, e59; doi:10.1038/mtna.2012.51; published online 4 December 2012. PMID:23212298

Borjigin, Mandula; Strouse, Bryan; Niamat, Rohina A; Bialk, Pawel; Eskridge, Chris; Xie, Jingwei; Kmiec, Eric B

2012-01-01

311

Maize centromeres expand and adopt a uniform size in the genetic background of oat  

PubMed Central

Most existing centromeres may have originated as neocentromeres that activated de novo from noncentromeric regions. However, the evolutionary path from a neocentromere to a mature centromere has been elusive. Here we analyzed the centromeres of nine chromosomes that were transferred from maize into oat as the result of an inter-species cross. Centromere size and location were assayed by chromatin immunoprecipitation for the histone variant CENH3, which is a defining feature of functional centromeres. Two isolates of maize chromosome 3 proved to contain neocentromeres in the sense that they had moved from the original site, whereas the remaining seven centromeres (1, 2, 5, 6, 8, 9, and 10) were retained in the same area in both species. In all cases, the CENH3-binding domains were dramatically expanded to encompass a larger area in the oat background (?3.6 Mb) than the average centromere size in maize (?1.8 Mb). The expansion of maize centromeres appeared to be restricted by the transcription of genes located in regions flanking the original centromeres. These results provide evidence that (1) centromere size is regulated; (2) centromere sizes tend to be uniform within a species regardless of chromosome size or origin of the centromere; and (3) neocentromeres emerge and expand preferentially in gene-poor regions. Our results suggest that centromere size expansion may be a key factor in the survival of neocentric chromosomes in natural populations.

Wang, Kai; Wu, Yufeng; Zhang, Wenli; Dawe, R. Kelly; Jiang, Jiming

2014-01-01

312

Biological safety concepts of genetically modified live bacterial vaccines.  

PubMed

Live vaccines possess the advantage of having access to induce cell-mediated and antibody-mediated immunity; thus in certain cases they are able to prevent infection, and not only disease. Furthermore, live vaccines, particularly bacterial live vaccines, are relatively cheap to produce and easy to apply. Hence they are suitable to immunize large communities or herds. The induction of both cell-mediated immunity as well as antibody-mediated immunity, which is particularly beneficial in inducing mucosal immune responses, is obtained by the vaccine-strain's ability to colonize and multiply in the host without causing disease. For this reason, live vaccines require attenuation of virulence of the bacterium to which immunity must be induced. Traditionally attenuation was achieved simply by multiple passages of the microorganism on growth medium, in animals, eggs or cell cultures or by chemical or physical mutagenesis, which resulted in random mutations that lead to attenuation. In contrast, novel molecular methods enable the development of genetically modified organisms (GMOs) targeted to specific genes that are particularly suited to induce attenuation or to reduce undesirable effects in the tissue in which the vaccine strains can multiply and survive. Since live vaccine strains (attenuated by natural selection or genetic engineering) are potentially released into the environment by the vaccinees, safety issues concerning the medical as well as environmental aspects must be considered. These involve (i) changes in cell, tissue and host tropism, (ii) virulence of the carrier through the incorporation of foreign genes, (iii) reversion to virulence by acquisition of complementation genes, (iv) exchange of genetic information with other vaccine or wild-type strains of the carrier organism and (v) spread of undesired genes such as antibiotic resistance genes. Before live vaccines are applied, the safety issues must be thoroughly evaluated case-by-case. Safety assessment includes knowledge of the precise function and genetic location of the genes to be mutated, their genetic stability, potential reversion mechanisms, possible recombination events with dormant genes, gene transfer to other organisms as well as gene acquisition from other organisms by phage transduction, transposition or plasmid transfer and cis- or trans-complementation. For this, GMOs that are constructed with modern techniques of genetic engineering display a significant advantage over random mutagenesis derived live organisms. The selection of suitable GMO candidate strains can be made under in vitro conditions using basic knowledge on molecular mechanisms of pathogenicity of the corresponding bacterial species rather than by in vivo testing of large numbers of random mutants. This leads to a more targeted safety testing on volunteers and to a reduction in the use of animal experimentation. PMID:17239999

Frey, Joachim

2007-07-26

313

Global market effects of alternative European responses to genetically modified organisms  

Microsoft Academic Search

Global Market Effects of Alternative European Responses to Genetically Modified Organisms. — Current debates about genetically\\u000a modified organisms (GMOs) in agriculture reveal substantial differences in the perception of the associated risks and benefits.\\u000a Genetically modified crop varieties allegedly provide farmers with agronomic benefits, but environmental, health and ethical\\u000a concerns are also being raised. This paper discusses the ways in which

Chantal Pohl Nielsen; Kym Anderson

2001-01-01

314

Biological and biomedical aspects of genetically modified food.  

PubMed

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. PMID:16298508

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

315

Exploring the structure of attitudes toward genetically modified food.  

PubMed

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. PMID:17184407

Poortinga, Wouter; Pidgeon, Nick F

2006-12-01

316

Environmental risk assessment for medicinal products containing genetically modified organisms.  

PubMed

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. PMID:19940966

Anliker, B; Longhurst, S; Buchholz, C J

2010-01-01

317

Risk assessment of genetically modified crops for nutrition and health.  

PubMed

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. PMID:19146501

Magaña-Gómez, Javier A; de la Barca, Ana M Calderón

2009-01-01

318

The case for genetically modified crops with a poverty focus.  

PubMed

Recently seven National Academies of Science produced a report on transgenic plants and world agriculture. The report provides scientific perspectives to the ongoing public debate about the potential role for transgenic technology in world agriculture. In this article, we develop the themes of the report and emphasize the potential for future genetically modified (GM) crops with a poverty focus, emphasizing the potential of GM resistance to plant parasitic nematodes for subsistence potato farmers in Bolivia. We judge that a range of incremental gains to crop yields from many transgenes are valuable for future world security. We advocate the establishment of a standard that GM crops must achieve before they are both biosafe and appropriate for resource-poor farmers and we believe that the best interests of the poor require biotechnologists to work towards that objective. PMID:11179801

Atkinson, H J; Green, J; Cowgill, S; Levesley, A

2001-03-01

319

Proteomic evaluation of genetically modified crops: current status and challenges  

PubMed Central

Hectares of genetically modified (GM) crops have increased exponentially since 1996, when such crops began to be commercialized. GM biotechnology, together with conventional breeding, has become the main approach to improving agronomic traits of crops. However, people are concerned about the safety of GM crops, especially GM-derived food and feed. Many efforts have been made to evaluate the unintended effects caused by the introduction of exogenous genes. “Omics” techniques have advantages over targeted analysis in evaluating such crops because of their use of high-throughput screening. Proteins are key players in gene function and are directly involved in metabolism and cellular development or have roles as toxins, antinutrients, or allergens, which are essential for human health. Thus, proteomics can be expected to become one of the most useful tools in safety assessment. This review assesses the potential of proteomics in evaluating various GM crops. We further describe the challenges in ensuring homogeneity and sensitivity in detection techniques.

Gong, Chun Yan; Wang, Tai

2013-01-01

320

National Centre for Biotechnology Education Genetically Modified Food  

NSDL National Science Digital Library

Following the recent decision of Bayer CropScience to withdraw its herbicide-tolerant fodder maize, Chardon LL, the soonest we are likely to see commercial cultivation of any GM crop in the UK is 2008 . This mini-site examines the history of GM food in the UK. This content is appropriate for teachers or as an extension.

2006-01-01

321

[Detection of genetically modified organisms obtained from food samples ].  

PubMed

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%. PMID:15568468

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

322

Low-nitrogen stress tolerance and nitrogen agronomic efficiency among maize inbreds: comparison of multiple indices and evaluation of genetic variation  

Microsoft Academic Search

Limited information is available on genetic variation in low-nitrogen (low-N) stress tolerance and N-use efficiency (NUE)\\u000a among maize inbreds. To unveil this information, a panel of 189 diverse maize inbred lines was evaluated under contrasting\\u000a levels of N availability over 2 years. Low-N agronomic efficiency (LNAE), absolute grain yield (GY) at low-N conditions, and\\u000a the ratio between GY at low-N and

Yongshen WuWenguo; Wenguo Liu; Xinhai Li; Mingshun Li; Degui Zhang; Zhuanfang Hao; Jianfeng Weng; Yunbi Xu; Li Bai; Shihuang Zhang; Chuanxiao Xie

2011-01-01

323

Genetic Architecture of Maize Kernel Composition in the Nested Association Mapping and Inbred Association Panels1[W  

PubMed Central

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.

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

324

Genetic analysis of fumonisin production and virulence of Gibberella fujikuroi mating population A (Fusarium moniliforme) on maize (Zea mays) seedlings.  

PubMed Central

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.

Desjardins, A E; Plattner, R D; Nelsen, T C; Leslie, J F

1995-01-01

325

Field decomposition of transgenic Bt maize residue and the impact on non-target soil invertebrates  

Microsoft Academic Search

Genetically modified Bacillus thuringiensis Berliner (Bt) maize (Zea mays L.) expressing Cry toxins against various target pests is now grown on more than 16 million hectares worldwide, but its potential\\u000a effects on the soil ecosystem need to be further investigated. In an 8-month field study, we investigated the effects of Bt\\u000a maize expressing the Cry1Ab protein on both the soil

C. Zwahlen; A. Hilbeck; W. Nentwig

2007-01-01

326

In vivo studies on possible health consequences of genetically modified food and feed--with particular regard to ingredients consisting of genetically modified plant materials.  

PubMed

This synopsis reviews published in vivo studies on possible health consequences of genetically modified food and feed where the ingredients in question have consisted of genetically modified plant materials. The following, however, have not been taken into consideration:--ingredients consisting of genetically modified microorganisms or parts of animals/fish--ingredients produced by/from genetically modified organisms but without any DNA present--studies on consequences for the environment or biodiversity--in vitro studies or computer simulations. According to a Norwegian report "Gen-mat" (NOU 2000:29), and a more recent search in Medline and Citations Index, to our knowledge a total of ten studies have been published on the health effects of GM-foods and feeds. In this minireview the data made available in these published studies is discussed. PMID:12803276

Pryme, Ian F; Lembcke, Rolf

2003-01-01

327

Genetic Variation for Starch Thermal and Functional Properties Among Nonmutant Maize Inbreds  

Microsoft Academic Search

Cereal Chem. 72(3):281-286 Differential scanning calorimetry (DSC) has been used in previous < 0.01) inbred by year interaction was present for all DSC parameters studies to detect differences in thermal properties among starches of non- with the exception of AH. Differences were observed in starch viscosities mutant maize (Zea mays L.) genotypes. This study was conducted to and gel strengths

M. R. CAMPBELL; L. M. POLLAK; P. J. WHITE

328

Genetic and physical fine mapping of Scmv2 , a potyvirus resistance gene in maize  

Microsoft Academic Search

Sugarcane mosaic virus (SCMV) is an important virus pathogen both in European and Chinese maize production, causing serious\\u000a losses in grain and forage yield in susceptible cultivars. Two major resistance loci confer resistance to SCMV, one located\\u000a on chromosome 3 (Scmv2) and one on chromosome 6 (Scmv1). We developed a large isogenic mapping population segregating in the Scmv2, but not

Christina Roenn Ingvardsen; Yongzhong Xing; Ursula Karoline Frei; Thomas Lübberstedt

2010-01-01

329

Invertebrate responses to the management of genetically modified herbicide-tolerant and conventional spring crops. I. Soil-surface-active invertebrates.  

PubMed Central

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.

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

330

Mapping quantitative trait loci using naturally occurring genetic variance among commercial inbred lines of maize (Zea mays L.).  

PubMed

Many commercial inbred lines are available in crops. A large amount of genetic variation is preserved among these lines. The genealogical history of the inbred lines is usually well documented. However, quantitative trait loci (QTL) responsible for the genetic variances among the lines are largely unexplored due to lack of statistical methods. In this study, we show that the pedigree information of the lines along with the trait values and marker information can be used to map QTL without the need of further crossing experiments. We develop a Monte Carlo method to estimate locus-specific identity-by-descent (IBD) matrices. These IBD matrices are further incorporated into a mixed-model equation for variance component analysis. QTL variance is estimated and tested at every putative position of the genome. The actual QTL are detected by scanning the entire genome. Applying this new method to a well-documented pedigree of maize (Zea mays L.) that consists of 404 inbred lines, we mapped eight QTL for the maize male flowering trait, growing degree day heat units to pollen shedding (GDUSHD). These detected QTL contributed >80% of the variance observed among the inbred lines. The QTL were then used to evaluate all the inbred lines using the best linear unbiased prediction (BLUP) technique. Superior lines were selected according to the estimated QTL allelic values, a technique called marker-assisted selection (MAS). The MAS procedure implemented via BLUP may be routinely used by breeders to select superior lines and line combinations for development of new cultivars. PMID:15716509

Zhang, Yuan-Ming; Mao, Yongcai; Xie, Chongqing; Smith, Howie; Luo, Lang; Xu, Shizhong

2005-04-01

331

Population genetics of duplicated disease-defense genes, hm1 and hm2, in maize (Zea mays ssp. mays L.) and its wild ancestor (Zea mays ssp. parviglumis).  

PubMed Central

Plant defense genes are subject to nonneutral evolutionary dynamics. Here we investigate the evolutionary dynamics of the duplicated defense genes hm1 and hm2 in maize and its wild ancestor Zea mays ssp. parviglumis. Both genes have been shown to confer resistance to the fungal pathogen Cochliobolus carbonum race 1, but the effectiveness of resistance differs between loci. The genes also display different population histories. The hm1 locus has the highest nucleotide diversity of any gene yet sampled in the wild ancestor of maize, and it contains a large number of indel polymorphisms. There is no evidence, however, that high diversity in hm1 is a product of nonneutral evolution. In contrast, hm2 has very low nucleotide diversity in the wild ancestor of maize. The distribution of hm2 polymorphic sites is consistent with nonneutral evolution, as indicated by Tajima's D and other neutrality tests. In addition, one hm2 haplotype is more frequent than expected under the equilibrium neutral model, suggesting hitchhiking selection. Both defense genes retain >80% of the level of genetic variation in maize relative to the wild ancestor, and this level is similar to other maize genes that were not subject to artificial selection during domestication.

Zhang, Liqing; Peek, Andrew S; Dunams, Detiger; Gaut, Brandon S

2002-01-01

332

Variegation patterns caused by excision of the maize transposable element Dissociation (Ds) are autonomously regulated by allele-specific Activator (Ac) elements and are not due to trans -acting modifier genes  

Microsoft Academic Search

The Ac elements present in the unstable wxm7 and wx-m9 alleles of maize trigger different patterns of Ds excision in trans. To determine whether this differential regulation is a feature of the Ac alleles themselves or is mediated by genetically distinct factors, maize plants heterozygous for the wx-m7 and wx-m9 alleles were crossed to tester strains homozygous for Ds reporter

Manfred Heinlein

1995-01-01

333

Perspectives of people in Mali toward genetically-modified mosquitoes for malaria control  

Microsoft Academic Search

BACKGROUND: Genetically-modified (GM) mosquitoes have been proposed as part of an integrated vector control strategy for malaria control. Public acceptance is essential prior to field trials, particularly since mosquitoes are a vector of human disease and genetically modified organisms (GMOs) face strong scepticism in developed and developing nations. Despite this, in sub-Saharan Africa, where the GM mosquito effort is primarily

John M Marshall; Mahamoudou B Touré; Mohamed M Traore; Shannon Famenini; Charles E Taylor

2010-01-01

334

Assessment of the food safety issues related to genetically modified foods  

Microsoft Academic Search

International consensus has been reached on the principles regarding evaluation of the food safety of genetically modified plants. The concept of substantial equivalence has been developed as part of a safety evaluation framework, based on the idea that existing foods can serve as a basis for comparing the properties of genetically modified foods with the appropriate counterpart. Application of the

Harry A. Kuiper; Gijs A. Kleter; Hub P. J. M. Noteborn; Esther J. Kok

2001-01-01

335

Public engagement in Japanese policy-making: a history of the genetically modified organisms debate  

Microsoft Academic Search

New laws regulating the use of genetically modified organisms have recently been enacted in Japan, and there were many stakeholders involved in the development of this policy. Our review of the history and the debates held in the course of policy development regarding genetically modified organisms in Japan shows that the current regulatory system was developed taking past national and

Ryuma Shineha; Kazuto Kato

2009-01-01

336

A design for the control of apoptosis in genetically modified Saccharomyces cerevisiae.  

PubMed

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. PMID:25036693

Nishida, Nao; Noguchi, Misa; Kuroda, Kouichi; Ueda, Mitsuyoshi

2014-02-01

337

Health Considerations Regarding Horizontal Transfer of Microbial Transgenes Present in Genetically Modified Crops  

PubMed Central

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.

Kleter, Gijs A.

2005-01-01

338

Maize proteomics: an insight into the biology of an important cereal crop.  

PubMed

Maize (Zea mays L.) is the most grown cereal crop in the world (839 million tons in 2012). According to its agro-economical importance, maize has received tremendous attention from research communities of academic, state, and industry origin. In this manuscript, we aspire to provide readers with the first comprehensive review of proteomics studies performed on maize within a 1987-2012 time period. The following topics are presented here: maize proteome profiling, developmental proteomics, response to abiotic and biotic stress, maize phosphoproteomics, tissue-specific wild-type versus mutant analyses, heterosis, seed viability, maize allergens, and safety assessment of genetically modified maize. Tissues, organelles, subcellular compartments, secretomes, methods, phenomena, and pertinent proteins were summarized and referenced in tables and figures to provide readers with expediently accessible information in the context of up-to-date achievements. This review illustrates maize proteomics as a firmly established research area with laboratories around the world diligently advancing our knowledge of diverse aspects of maize biology. PMID:23197376

Pechanova, Olga; Taká?, Tomáš; Samaj, Jozef; Pechan, Tibor

2013-02-01

339

Fast and sensitive detection of genetically modified yeasts in wine.  

PubMed

In this work, a novel screening methodology based on the combined use of multiplex polymerase chain reaction (PCR) and capillary gel electrophoresis with laser induced fluorescence (CGE-LIF) is developed for the fast and sensitive detection of genetically modified yeasts in wine. As model, a recombinant EKD-13 Saccaromyces cerevisiae strain was selected and different wines were prepared using either recombinant or conventional yeasts. Special emphasis is put on the yeast DNA extraction step, exploring different commercial and non-commercial methods, in order to overcome the important difficulty of obtaining amplifiable DNA from wine samples. To unequivocally detect the transgenic yeast, two specific segments of the transgenic construction were amplified. In addition, a third primer pair was used as amplification control to confirm the quality of the yeast DNA obtained from the extraction step. CGE-LIF provides high sensitivity, good analysis speed and impressive resolution of DNA fragments, making this technique very convenient to optimize multiplex PCR parameters and to analyze the amplified DNA fragments. Thus, the CGE-LIF method provided %RSD values for DNA migration times lower than 0.82% (n=10) with the same capillary and lower than 1.92% (n=15) with three different capillaries, allowing the adequate size determination of the PCR products with an error lower than 4% compared to the theoretically expected. The whole method developed in this work requires less than one working day and grants the sensitive detection of transgenic yeasts in wine samples. PMID:21296357

León, Carlos; García-Cañas, Virginia; González, Ramón; Morales, Pilar; Cifuentes, Alejandro

2011-10-21

340

Genetically modified cotton in India and detection strategies.  

PubMed

India is one of the largest cotton-growing countries. Cotton is a fiber crop with varied applications from making tiny threads to fashionable clothing in the textile sector. In the near future, cotton crop will gain popularity as a multipurpose crop in India. The commercialization of Bt cotton in 2002 and consequently the fast adoption of Bt cotton hybrids by cotton farmers have enhanced the cotton production in India. Presently, genetically modified (GM) cotton has occupied 21.0 million hectares (mha) that comprise 14% of the global area under GM cultivation. In the coming years, improved cotton hybrids, with stacked and multiple gene events for improved fiber quality, insect resistance, drought tolerance, and herbicide tolerance, would further significantly improve the cotton production in India. With the dramatic increase in commercialization of GM crops, there is an urgent need to develop cost-effective and robust GM detection methods for effective risk assessment and management, post release monitoring, and to solve the legal disputes. DNA-based GM diagnostics are most robust assays due to their high sensitivity, specificity, and stability of DNA molecule. PMID:23143480

Randhawa, Gurinder Jit; Chhabra, Rashmi

2013-01-01

341

Improved properties of micronized genetically modified flax fibers.  

PubMed

The aim of this study was to investigate the effect of micronization on the compound content, crystalline structure and physicochemical properties of fiber from genetically modified (GM) flax. The GM flax was transformed with three bacterial (Ralstonia eutropha) genes coding for enzymes of polyhydroxybutyrate (PHB) synthesis and under the control of the vascular bundle promoter. The modification resulted in fibers containing the 3-hydroxybutyrate polymer bound to cellulose via hydrogen and ester bonds and antioxidant compounds (phenolic acids, vanillin, vitexin, etc.). The fibers appeared to have a significantly decreased particle size after 20h of ball-milling treatment. Micronized fibers showed reduced phenolic contents and antioxidant capacity compared to the results for untreated fibers. An increased level of PHB was also detected. Micronization introduces structural changes in fiber constituents (cellulose, hemicellulose, pectin, lignin, PHB) and micronized fibers exhibit more functional groups (hydroxyl, carboxyl) derived from those constituents. It is thus concluded that micronization treatments improve the functional properties of the fiber components. PMID:23353730

Dymi?ska, Lucyna; Szatkowski, Micha?; Wróbel-Kwiatkowska, Magdalena; Zuk, Magdalena; Kurzawa, Adam; Syska, Wojciech; G?gor, Anna; Zawadzki, Miros?aw; Ptak, Maciej; M?czka, Miros?aw; Hanuza, Jerzy; Szopa, Jan

2012-12-15

342

Electrochemiluminescence-PCR detection of genetically modified organisms  

NASA Astrophysics Data System (ADS)

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.

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

2005-01-01

343

Interval timing in genetically modified mice: a simple paradigm  

PubMed Central

We describe a behavioral screen for the quantitative study of interval timing and interval memory in mice. Mice learn to switch from a short-latency feeding station to a long-latency station when the short latency has passed without a feeding. The psychometric function is the cumulative distribution of switch latencies. Its median measures timing accuracy and its interquartile interval measures timing precision. Next, using this behavioral paradigm, we have examined mice with a gene knockout of the receptor for gastrin-releasing peptide that show enhanced (i.e. prolonged) freezing in fear conditioning. We have tested the hypothesis that the mutants freeze longer because they are more uncertain than wild types about when to expect the electric shock. The knockouts however show normal accuracy and precision in timing, so we have rejected this alternative hypothesis. Last, we conduct the pharmacological validation of our behavioral screen using D-amphetamine and methamphetamine. We suggest including the analysis of interval timing and temporal memory in tests of genetically modified mice for learning and memory and argue that our paradigm allows this to be done simply and efficiently.

Balci, F.; Papachristos, E. B.; Gallistel, C. R.; Brunner, D.; Gibson, J.; Shumyatsky, G. P.

2009-01-01

344

Examining consumer behavior toward genetically modified (GM) food in Britain.  

PubMed

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. PMID:16834625

Spence, Alexa; Townsend, Ellen

2006-06-01

345

Aphid-parasitoid community structure on genetically modified wheat  

PubMed Central

Since the introduction of genetically modified (GM) plants, one of the main concerns has been their potential effect on non-target insects. Many studies have looked at GM plant effects on single non-target herbivore species or on simple herbivore–natural enemy food chains. Agro-ecosystems, however, are characterized by numerous insect species which are involved in complex interactions, forming food webs. In this study, we looked at transgenic disease-resistant wheat (Triticum aestivum) and its effect on aphid–parasitoid food webs. We hypothesized that the GM of the wheat lines directly or indirectly affect aphids and that these effects cascade up to change the structure of the associated food webs. Over 2 years, we studied different experimental wheat lines under semi-field conditions. We constructed quantitative food webs to compare their properties on GM lines with the properties on corresponding non-transgenic controls. We found significant effects of the different wheat lines on insect community structure up to the fourth trophic level. However, the observed effects were inconsistent between study years and the variation between wheat varieties was as big as between GM plants and their controls. This suggests that the impact of our powdery mildew-resistant GM wheat plants on food web structure may be negligible and potential ecological effects on non-target insects limited.

von Burg, Simone; van Veen, Frank J. F.; Alvarez-Alfageme, Fernando; Romeis, Jorg

2011-01-01

346

Gene Flow from Genetically Modified Rice and Its Environmental Consequences  

NSDL National Science Digital Library

This peer-reviewed article from BioScience journal is about the environmental consequences of genetically modified rice. Within the next few years, many types of transgenic rice (Oryza sativa) will be ready for commercialization, including varieties with higher yields, greater tolerance of biotic and abiotic stresses, resistance to herbicides, improved nutritional quality, and novel pharmaceutical proteins. Although rice is primarily self-pollinating, its transgenes are expected to disperse to nearby weedy and wild relatives through pollen-mediated gene flow. Sexually compatible Oryza species often co-occur with the crop, especially in tropical countries, but little is known about how quickly fitness-enhancing transgenes will accumulate in these populations and whether this process will have any unwanted environmental consequences. For example, weedy rice could become much more difficult to manage if it acquires herbicide resistance, produces more seeds, or occurs in a wider range of habitats because of the spread of certain transgenes. Rice-growing countries urgently need publicly available ecological assessments of the risks and benefits of transgenic rice before new varieties are released.

BAO-RONG LU and ALLISON A. SNOW (;)

2005-08-01

347

New qualitative detection methods of genetically modified potatoes.  

PubMed

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. PMID:15340215

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

348

Genetically modified potato plants in nutrition and prevention of diseases in humans and animals: a review  

Microsoft Academic Search

Genetically modified organisms (GMO) become a real constituent of our lives and nowadays, they are commonly introduced into the food chain of people and animals in some states. Among higher organisms, plants are used above all for genetic modifications; potatoes are a suitable model plants for this purpose. Nowa- days, a number of various genetic modifications of potato plants are

R. PRIBYLOVA; I. PAVLIK; M. BARTOS

2006-01-01

349

Clinical and laboratory investigation of allergy to genetically modified foods.  

PubMed Central

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.

Bernstein, Jonathan A; Bernstein, I Leonard; Bucchini, Luca; Goldman, Lynn R; Hamilton, Robert G; Lehrer, Samuel; Rubin, Carol; Sampson, Hugh A

2003-01-01

350

Evaluation of catalytic free energies in genetically modified proteins.  

PubMed

A combination of the empirical valence bond method and a free energy perturbation approach is used to simulate the activity of genetically modified enzymes. The simulations reproduce in a semiquantitative way the observed effects of mutations on the activity and binding free energies of trypsin and subtilisin. This suggests that we are approaching a stage of quantitative structure-function correlation of enzymes. The analysis of the calculations points towards the electrostatic energy of the reacting system as the key factor in enzyme catalysis. The changes in the charges of the reacting system and the corresponding changes in "solvation" free energy (generalized here as the interaction between the charges and the given microenvironment) are emphasized. It is argued that a reliable evaluation of these changes might be sufficient for correlating structure and catalysis. The use of free energy perturbation methods and thermodynamic cycles for evaluation of solvation energies and reactivity is discussed, pointing out our early contributions. The apparent elaborated nature of our treatment is clarified, explaining that such a treatment is essential for consistent calculations of chemical reactions in polar environments. The problems associated with seemingly more rigorous quantum mechanical methods are discussed, emphasizing the inconsistency associated with using gas phase charge distributions. The importance of dynamic aspects is examined by evaluating the autocorrelation of the protein "reaction field" on the reacting substrate. It is found that, at least in the present case, dynamic effects are not important. The nature of the catalytic free energy is considered, arguing that the protein provides preoriented dipoles (polarized to stabilize the transition state charge distribution) and small reorganization energy, thus reducing the activation free energy. The corresponding catalytic free energy is related to the folding free energy, which is being invested in aligning the active site dipoles. PMID:3047396

Warshel, A; Sussman, F; Hwang, J K

1988-05-01

351

Transgene x Environment Interactions in Genetically Modified Wheat  

PubMed Central

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.

Zeller, Simon L.; Kalinina, Olena; Brunner, Susanne; Keller, Beat; Schmid, Bernhard

2010-01-01

352

Single-Kernel Ionomic Profiles Are Highly Heritable Indicators of Genetic and Environmental Influences on Elemental Accumulation in Maize Grain (Zea mays)  

PubMed Central

The ionome, or elemental profile, of a maize kernel can be viewed in at least two distinct ways. First, the collection of elements within the kernel are food and feed for people and animals. Second, the ionome of the kernel represents a developmental end point that can summarize the life history of a plant, combining genetic programs and environmental interactions. We assert that single-kernel-based phenotyping of the ionome is an effective method of analysis, as it represents a reasonable compromise between precision, efficiency, and power. Here, we evaluate potential pitfalls of this sampling strategy using several field-grown maize sample sets. We demonstrate that there is enough genetically determined diversity in accumulation of many of the elements assayed to overcome potential artifacts. Further, we demonstrate that environmental signals are detectable through their influence on the kernel ionome. We conclude that using single kernels as the sampling unit is a valid approach for understanding genetic and environmental effects on the maize kernel ionome.

Baxter, Ivan R.; Ziegler, Gregory; Lahner, Brett; Mickelbart, Michael V.; Foley, Rachel; Danku, John; Armstrong, Paul; Salt, David E.; Hoekenga, Owen A.

2014-01-01

353

Fate of Transgenic DNA from Orally Administered Bt MON810 Maize and Effects on Immune Response and Growth in Pigs  

Microsoft Academic Search

We assessed the effect of short-term feeding of genetically modified (GM: Bt MON810) maize on immune responses and growth in weanling pigs and determined the fate of the transgenic DNA and protein in-vivo. Pigs were fed a diet containing 38.9% GM or non-GM isogenic parent line maize for 31 days. We observed that IL-12 and IFN? production from mitogenic stimulated

Maria C. Walsh; Stefan G. Buzoianu; Gillian E. Gardiner; Mary C. Rea; Eva Gelencsér; Anna Jánosi; Michelle M. Epstein; R. Paul Ross; Peadar G. Lawlor

2011-01-01

354

Diversity of bacterial communities in the rhizosphere and root interior of field-grown genetically modified Brassica napus  

Microsoft Academic Search

Plant roots significantly affect microbial diversity in soil, but little is known on how genetically modified plants influence soil microbial communities. We conducted a 2-year field study to assess the effects of herbicide-tolerant genetically modified canola (oilseed rape, Brassica sp.) on microbial biodiversity in the rhizosphere. During the 1998 and 1999 field seasons, four genetically modified and four conventional canola

Kari E Dunfield; James J Germida

2001-01-01

355

Detection of DNA of genetically modified maize by a silicon nanowire field-effect transistor  

Microsoft Academic Search

A silicon nanowire field-effect transistor based sensor (SiNW-FET) has been proved to be the most sensitive and powerful device for bio-detection applications. In this paper, SiNWs were first fabricated by using our recently developed deposition and etching under angle technique (DEA), then used to build up the complete SiNW device based biosensor. The fabricated SiNW biosensor was used to detect

Van Binh Pham; Xuan Thanh Tung Pham; Ngoc Thuy Duong Dang; Thi Thanh Tuyen Le; Phu Duy Tran; Thanh Chien Nguyen; Van Quoc Nguyen; Mau Chien Dang; Cees J M van Rijn; Duy Hien Tong

2011-01-01

356

Molecular toolbox for the identification of unknown genetically modified organisms.  

PubMed

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 sequence. The results demonstrate that the new methods complement routine screening procedures by providing direct conclusive evidence and may also be useful to resolve masking of unknown events by known events. PMID:19937431

Ruttink, Tom; Demeyer, Rolinde; Van Gulck, Elke; Van Droogenbroeck, Bart; Querci, Maddalena; Taverniers, Isabel; De Loose, Marc

2010-03-01

357

Genetically Modified Porcine Skin Grafts for Treatment of Severe Burn Injuries.  

National Technical Information Service (NTIS)

The most significant research findings in this time period include: 1) data supporting the effectiveness of skin grafts from genetically-modified swine transplanted onto full-thickness wounds on baboons when compared to the standard treatment (allogeneic ...

D. Sachs

2011-01-01

358

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...

359

Growth promotion of genetically modified hematopoietic progenitors using an antibody\\/c-Mpl chimera  

Microsoft Academic Search

Thrombopoietin is a potent cytokine that exerts proliferation of hematopoietic stem cells (HSCs) through its cognate receptor, c-Mpl. Therefore, mimicry of c-Mpl signaling by a receptor recognizing an artificial ligand would be attractive to attain specific expansion of genetically modified HSCs. Here we propose a system enabling selective expansion of genetically modified cells using an antibody\\/receptor chimera that can be

Masahiro Kawahara; Jianhong Chen; Takahiro Sogo; Jinying Teng; Makoto Otsu; Masafumi Onodera; Hiromitsu Nakauchi; Hiroshi Ueda; Teruyuki Nagamune

2011-01-01

360

Regulations governing veterinary medicinal products containing genetically modified organisms in the European Community  

Microsoft Academic Search

Summary This paper describes particular aspects of the marketing of veterinary medicinal products (VMPs) that contain or consist of genetically modified micro-organisms (GMMs) or genetically modified organisms (GMOs). The regulatory requirements and the procedures applied in the European Union for each phase (pre-marketing, authorisation process, and post-authorisation labelling and monitoring) are explained. In most cases VMPs are subject to both

G. Moulin

361

Transgenes in Mexican maize: molecular evidence and methodological considerations for GMO detection in landrace populations  

Microsoft Academic Search

A possible consequence of planting genetically modified organisms (GMOs) in centres of crop origin is unintended gene flow into traditional landraces. In 2001, a study reported the presence of the transgenic 35S promoter in maize landraces sampled in 2000 from the Sierra Juarez of Oaxaca, Mexico. Analysis of a large sample taken from the same region in 2003 and 2004

A. Pineyro-Nelson; J. VAN HEERWAARDEN; H. R. Perales; J. A. Serratos-Hernandez; A. Rangel; M. B. Hufford; P. Gepts; A. Garay-Arroyo; R. Rivera-Bustamante; E. R. Alvarez-Buylla

2009-01-01

362

Plant color effects of certain anomalous forms of the R r allele in maize  

Microsoft Academic Search

The genetically changes forms ofRrarising regularly in maize plants heterozygous for the stippled, light stippled, and marbled alleles, and previously shown to influence aleurone color differentially, were found to affect coleoptile and seedling leaf sheath color also. Failure to demonstrate corresponding differential effects on root pigmentation possibly was due to inadequacy of the testing procedure. Two of the modified forms

R. A. Brink; B. Mikula

1958-01-01

363

Host-plant mediated effects of transgenic maize on the insect parasitoid Campoletis sonorensis (Hymenoptera: Ichneumonidae)  

Microsoft Academic Search

Determining the impact of genetically modified (GM) crops on beneficial organisms is an important aspect of the environmental risk assessment of GM crops. In the present study, the impact of Bt maize expressing Cry1Ab on the development and behaviour of the parasitoid Campoletis sonorensis was compared to individuals reared on hosts fed conventionally bred plants partially resistant to the European

Christopher J. Sanders; Judith K. Pell; Guy M. Poppy; Alan Raybould; Monica Garcia-Alonso; Tanja H. Schuler

2007-01-01

364

Development of a peptide nucleic acid array platform for the detection of genetically modified organisms in food.  

PubMed

Two previously developed platforms, a multiplex polymerase chain reaction (PCR) and a peptide nucleic acid (PNA) array, the former allowing for the simultaneous detection of five transgenes and two endogenous controls in food and feed matrices and the latter for the assessment of the identity of amplified PCR products, were combined in order to develop a PNA array device for the screening of genetically modified organisms (GMOs) in food. PNA probes were opportunely designed, synthesized, and deposited on commercial slides. The length of the probes as well as the distance of the probes from the surface were evaluated and found to be critical points. The most suitable probes were found to be 15-mer PNAs linked to the slide surface by means of two 2-(2-aminoethoxy)ethoxyacetic acids as spacers. The device was tested on a model system constituted by flour samples containing a mixture of standards at known concentrations of transgenic material, in particular Roundup Ready soybean and Bt11, Bt176, Mon810, and GA21 maize: The DNA was amplified using the specific multiplex PCR method and tested on the PNA array. The method proposed was found to be able to correctly identify every GMO present in the tested samples. PMID:15884823

Germini, Andrea; Rossi, Stefano; Zanetti, Alessandro; Corradini, Roberto; Fogher, Corrado; Marchelli, Rosangela

2005-05-18

365

Development of sampling approaches for the determination of the presence of genetically modified organisms at the field level.  

PubMed

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. PMID:20069281

Sustar-Vozlic, Jelka; Rostohar, Katja; Blejec, Andrej; Kozjak, Petra; Cergan, Zoran; Meglic, Vladimir

2010-03-01

366

Individual maize chromosomes in the C(3) plant oat can increase bundle sheath cell size and vein density.  

PubMed

C(4) photosynthesis has evolved in at least 66 lineages within the angiosperms and involves alterations to the biochemistry, cell biology, and development of leaves. The characteristic "Kranz" anatomy of most C(4) leaves was discovered in the 1890s, but the genetic basis of these traits remains poorly defined. Oat × maize addition lines allow the effects of individual maize (Zea mays; C(4)) chromosomes to be investigated in an oat (Avena sativa; C(3)) genetic background. Here, we have determined the extent to which maize chromosomes can introduce C(4) characteristics into oat and have associated any C(4)-like changes with specific maize chromosomes. While there is no indication of a simultaneous change to C(4) biochemistry, leaf anatomy, and ultrastructure in any of the oat × maize addition lines, the C(3) oat leaf can be modified at multiple levels. Maize genes encoding phosphoenolpyruvate carboxylase, pyruvate, orthophosphate dikinase, and the 2'-oxoglutarate/malate transporter are expressed in oat and generate transcripts of the correct size. Three maize chromosomes independently cause increases in vein density, and maize chromosome 3 results in larger bundle sheath cells with increased cell wall lipid deposition in oat leaves. These data provide proof of principle that aspects of C(4) biology could be integrated into leaves of C(3) crops. PMID:22675083

Tolley, Ben J; Sage, Tammy L; Langdale, Jane A; Hibberd, Julian M

2012-08-01

367

Consumers' Perceptions about Genetically Modified Foods and Their Stated Willingness-to-Pay for Genetically Modified Food Labeling: Evidences from Turkey  

Microsoft Academic Search

We applied a multinomial logit model to determine consumer characteristics affecting three possible policy regulations that wanted to be implemented for genetically modified foods in Turkey. The study reveals that many household characteristics including food spending amount, education, gender, marital status, knowledge about food related policies and regional variables are key policy factors to choose regulation programs on GMO foods.

Bahri Karli; Abdulbaki Bilgic; Bulent Miran

2008-01-01

368

Physiological and genetic characterization of end-of-day far-red light response in maize seedlings.  

PubMed

Developmental responses associated with end-of-day far-red light (EOD-FR) signaling were investigated in maize (Zea mays subspecies mays) seedlings. A survey of genetically diverse inbreds of temperate and tropical/semitropical origins, together with teosinte (Zea mays subspecies parviglumis) and a modern hybrid, revealed distinct elongation responses. A mesocotyl elongation response to the EOD-FR treatment was largely absent in the tropical/semitropical lines, but both hybrid and temperate inbred responses were of the same magnitude as in teosinte, suggesting that EOD-FR-mediated mesocotyl responses were not lost during the domestication or breeding process. The genetic architecture underlying seedling responses to EOD-FR was investigated using the intermated B73 x Mo17 mapping population. Among the different quantitative trait loci identified, two were consistently detected for elongation and responsiveness under EOD-FR, but none were associated with known light signaling loci. The central role of phytochromes in mediating EOD-FR responses was shown using a phytochromeB1 phytochromeB2 (phyB1 phyB2) mutant series. Unlike the coleoptile and first leaf sheath, EOD-FR-mediated elongation of the mesocotyl appears predominantly controlled by gibberellin. EOD-FR also reduced abscisic acid (ABA) levels in the mesocotyl for both the wild type and phyB1 phyB2 double mutants, suggesting a FR-mediated but PHYB-independent control of ABA accumulation. EOD-FR elongation responses were attenuated in both the wild type and phyB1 phyB2 double mutants when a chilling stress was applied during the dark period, concomitant with an increase in ABA levels. We present a model for the EOD-FR response that integrates light and hormonal control of seedling elongation. PMID:20668057

Dubois, Patrice G; Olsefski, Gregory T; Flint-Garcia, Sherry; Setter, Tim L; Hoekenga, Owen A; Brutnell, Thomas P

2010-09-01

369

Implications of Genetically Modified Food Technology Policies for Sub-Saharan Africa  

Microsoft Academic Search

The first generation of genetically modified (GM) crop varieties sought to increase farmer profitability through cost reductions or higher yields. The next generation of GM food research is focusing also on breeding for attributes of interest to consumers, beginning with ?golden rice,? which has been genetically engineered to contain a higher level of vitamin A and thereby boost the health

Kym Anderson; Lee Ann Jackson

2004-01-01

370

Genetically Modified Crops and Nuisance: Exploring the Role of Precaution in Private Law  

ERIC Educational Resources Information Center

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…

Craik, Neil; Culver, Keith; Siebrasse, Norman

2007-01-01

371

Mutant and genetically modified mice as models for studying the relationship between aging and carcinogenesis  

Microsoft Academic Search

Increased interest is emerging in using mouse models to assess the genetics of aging and age-related diseases, including cancer. However, only limited information is available regarding the relationship between aging and spontaneous tumor development in genetically modified mice. Analysis of various transgenic and knockout rodent models with either a shortened or an extended life span, provides a unique opportunity to

Vladimir N Anisimov

2001-01-01

372

Erratum: Invasion of transgenes from salmon or other genetically modified organisms into natural populations  

Microsoft Academic Search

In recent years, there has been widespread concern about the ecological and genetic effects of genetically modified organisms. In salmon and other fishes, transgenic growth hormone genes have been shown to have large ef- fects on size and various traits related to fitness. In this paper, I have shown by using a deterministic model that if such a transgene has

Philip W. Hedrick

2001-01-01

373

EU–US Trade Disputes about Risk Regulation: The Case of Genetically Modified Organisms  

Microsoft Academic Search

The cultivation of crops increasingly employs genetically modified organisms worldwide. The nature and the probability of side and latent effects of the mass use of genetic engineering are, at present, unforeseeable. A trade-off between risks and benefits is therefore hard to define. The precautionary principle is a globally known though not undisputed approach to handling such uncertainties. Its application is

Arno Scherzberg

2006-01-01

374

Comparison of Tuber Proteomes of Potato Varieties, Landraces, and Genetically Modified Lines1  

Microsoft Academic Search

Crop improvement by genetic modification remains controversial, one of the major issues being the potential for unintended effects. Comparative safety assessment includes targeted analysis of key nutrients and antinutritional factors, but broader scale-profiling or ''omics'' methods could increase the chances of detecting unintended effects. Comparative assessment should consider the extent of natural variation and not simply compare genetically modified (GM)

Satu J. Lehesranta; Howard V. Davies; Louise V. T. Shepherd; Naoise Nunan; Jim W. McNicol; Seppo Auriola; Kaisa M. Koistinen; Soile Suomalainen; Harri I. Kokko; Sirpa O. Karenlampi

375

The Fate of Genetically Modified Protein from Roundup Ready Soybeans in Laying Hens1  

Microsoft Academic Search

SUMMARY A study was conducted to determine the extent of genetically modified (GM) protein from Roundup Ready Soybeans in tissues and eggs of laying hens. Because a breakdown of the modified portion of protein was expected due to the digestive process of the hen, an immunoassay test was run. By using a double antibody sandwich format specific for the CP4

J. Ash; C. Novak; S. E. Scheideler

376

[Principles of production of genetically modified food sources].  

PubMed

Methods of genetic engineering have given a powerful impulse to the development of fundamental and applied biology and biotechnology of plants. Methods of genetic plant transformation, such as agrobacterium-mediated and microprojectile bombardment-mediated transformation have been used for a long time. These methods allow production of transgenic plants which express the genes of interest. Dozens of transgenic plants have been obtained by now, and their number is steadily increasing. PMID:16320704

Kirpichnikov, M P; Tyshko, N V

2005-01-01

377

Do You Really Know What You're Eating? A Case Study on Genetically Modified Foods  

NSDL National Science Digital Library

Starting from a fictional “news” report about an apparent allergic reaction to a taco tainted by genetically modified corn, students consider some of the techniques and procedures used in modern molecular genetics and microbiology as well as some of the issues associated with genetically modified organisms (GMOs). Originally designed for role-play and PowerPoint assignments, suggestions for a shortened version are also provided. Suitable for a general microbiology course, the case could also be used in an introductory molecular biology course with appropriate modifications. Various levels of coverage of the topic of recombinant DNA are possible.

Shew, Wayne; Reese, Mary C.

2007-01-01

378

Kin recognition within a seed and the effect of genetic relatedness of an endosperm to its compatriot embryo on maize seed development  

PubMed Central

As one of two sexual products resulting from double fertilization in angiosperms, the endosperm nourishes its compatriot embryo during seed development and/or germination and ultimately dies. Theoretical studies suggest that the genetic relatedness of an endosperm to its embryo in the same seed might determine the amount of resources ultimately available for the embryo during seed development. We took advantage of the phenomenon of heterofertilization in cultivated maize to empirically test whether genetic relatedness between a triploid embryo-nourishing endosperm and its compatriot diploid embryo impacts the process of resource allocation between these two sexually produced entities. We used genetically distinct maize inbred lines to perform two crossing experiments. Dry weights of dissected embryos and endosperms of mature heterofertilized and adjacent homofertilized kernels were compared. Embryo weight of heterofertilized kernels was significantly less than that of embryos of homofertilized kernels, whereas there was no significant difference in endosperm weight between the two types of kernels. Our results suggest that the degree of genetic relatedness of an endosperm to its compatriot embryo affects seed development and specifically the amount of maternal resources allocated to an endosperm that are eventually turned over to an embryo. The lower the coefficient of relatedness of an endosperm to its compatriot embryo, the smaller the embryo. Thus, the endosperm of a heterofertilized seed appears to behave less cooperatively with respect to resource transfer toward its less closely related embryo compared with the endosperm of a homofertilized seed.

Wu, Chi-Chih; Diggle, Pamela K.; Friedman, William E.

2013-01-01

379

Invertebrates and vegetation of field margins adjacent to crops subject to contrasting herbicide regimes in the Farm Scale Evaluations of genetically modified herbicide-tolerant crops.  

PubMed Central

The effects of management of genetically modified herbicide-tolerant (GMHT) crops on adjacent field margins were assessed for 59 maize, 66 beet and 67 spring oilseed rape sites. Fields were split into halves, one being sown with a GMHT crop and the other with the equivalent conventional non-GMHT crop. Margin vegetation was recorded in three components of the field margins. Most differences were in the tilled area, with fewer smaller effects mirroring them in the verge and boundary. In spring oilseed rape fields, the cover, flowering and seeding of plants were 25%, 44% and 39% lower, respectively, in the GMHT uncropped tilled margins. Similarly, for beet, flowering and seeding were 34% and 39% lower, respectively, in the GMHT margins. For maize, the effect was reversed, with plant cover and flowering 28% and 67% greater, respectively, in the GMHT half. Effects on butterflies mirrored these vegetation effects, with 24% fewer butterflies in margins of GMHT spring oilseed rape. The likely cause is the lower nectar supply in GMHT tilled margins and crop edges. Few large treatment differences were found for bees, gastropods or other invertebrates. Scorching of vegetation by herbicide-spray drift was on average 1.6% on verges beside conventional crops and 3.7% beside GMHT crops, the difference being significant for all three crops.

Roy, D B; Bohan, D A; Haughton, A J; Hill, M O; Osborne, J L; Clark, S J; Perry, J N; Rothery, P; Scott, R J; Brooks, D R; Champion, G T; Hawes, C; Heard, M S; Firbank, L G

2003-01-01

380

Genetically Modified T Cells for the Treatment of Malignant Disease  

PubMed Central

Summary The broaden application of adoptive T-cell transfer has been constrained by the technical abilities to isolate and expand antigen-specific T cells potent to selectively kill tumor cells. With the recent progress in the design and manufacturing of cellular products, T cells used in the treatment of malignant diseases may be regarded as anticancer biopharmaceuticals. Genetical manipulation of T cells has given T cells desired specificity but also enable to tailor their activation and proliferation potential. Here, we summarize the recent developments in genetic engineering of T-cell-based biopharmaceuticals, covering criteria for their clinical application in regard to safety and efficacy.

Wieczorek, Agnieszka; Uharek, Lutz

2013-01-01

381

Systemic Delivery of Recombinant Proteins by Genetically Modified Myoblasts  

Microsoft Academic Search

The ability to stably deliver recombinant proteins to the systemic circulation would facilitate the treatment of a variety of acquired and inherited diseases. To explore the feasibility of the use of genetically engineered myoblasts as a recombinant protein delivery system, stable transfectants of the murine C2C12 myoblast cell line were produced that synthesize and secrete high levels of human growth

Eliav Barr; Jeffrey M. Leiden

1991-01-01

382

Genetic mechanisms and modifying factors in hereditary hemochromatosis  

Microsoft Academic Search

Primary iron overload is one of the most common inherited diseases worldwide. Several genetic mutations underlie the various forms of the disease, which have similar pathophysiological profiles but distinct clinical presentations. Patients with hereditary hemochromatosis absorb too much iron from the diet, which accumulates over time within parenchymal cells. This accumulation leads to eventual organ failure as a consequence of

Günter Weiss

2009-01-01

383

Memory and behavior: a second generation of genetically modified mice  

Microsoft Academic Search

The use of standard genetic techniques, such as gene targeting and transgenesis, to study cognitive function in adult animals suffers from the limitations that the gene under study is often altered in many brain regions, and that this alteration is present during the entire developmental history of the animal. Furthermore, to relate cognitive defects to neuronal mechanisms of memory, studies

Mark Mayford; Isabelle M Mansuy; Robert U Muller; Eric R Kandel

1997-01-01

384

Genetic Rearrangements Can Modify Chromatin Features at Epialleles  

Microsoft Academic Search

Analogous to genetically distinct alleles, epialleles represent heritable states of different gene expression from sequence-identical genes. Alleles and epialleles both contribute to phenotypic heterogeneity. While alleles originate from mutation and recombination, the source of epialleles is less well understood. We analyze active and inactive epialleles that were found at a transgenic insert with a selectable marker gene in Arabidopsis. Both

Andrea M. Foerster; Huy Q. Dinh; Laura Sedman; Bonnie Wohlrab; Ortrun Mittelsten Scheid

2011-01-01

385

Reasonable Foreseeability and Liability in Relation to Genetically Modified Organisms  

ERIC Educational Resources Information Center

This article examines problems that may arise when addressing liability resulting from the genetic modification of microbes, animals, and plants. More specifically, it evaluates how uncertainties relating to the outcomes of these biotechnological innovations affect--or may affect--the courts' application of the reasonable foreseeability…

Khoury, Lara; Smyth, Stuart

2007-01-01

386

Genetically Modified Food: Knowledge and Attitude of Teachers and Students  

ERIC Educational Resources Information Center

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…

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

2010-01-01

387

ASSESSING POSSIBLE ECOLOGICAL RISKS OF GENETICALLY MODIFIED CROPS: GENE EXPRESSION ASSAYS AND GENETIC MONITORING OF NON-TARGET ORGANISMS  

EPA Science Inventory

Widespread planting of genetically modified crops with the Bt transgene pesticide has led to concern over non-target effects of Bt compounds in agroecosystems. While some research suggests that non-target organisms exposed to Bt toxin exhibit reduced fecundity and increased morta...

388

Implementation of genetic algorithm and modified shuffled frog leaping algorithm for transmission loss minimum re-scheduling  

Microsoft Academic Search

A transmission loss minimum re-scheduling method by genetic algorithm and modified shuffled frog leaping algorithm are proposed. The problem is a complex mixed integer programming problem. A genetic algorithm (GA) is a search or optimization algorithm based on the mechanics of natural selection and natural genetics where modified shuffled frog-leaping algorithm (MSFLA), which is an improved version of memetic algorithm,

Priyanka Roy; A. Chakrabarti

2011-01-01

389

[Hypothetical link between endometriosis and xenobiotics-associated genetically modified food].  

PubMed

Endometriosis is an oestrogen-dependent inflammatory disease affecting 10 % of reproductive-aged women. Often accompanied by chronic pelvic pain and infertility, endometriosis rigorously interferes with women's quality of life. Although the pathophysiology of endometriosis remains unclear, a growing body of evidence points to the implication of environmental toxicants. Over the last decade, an increase in the incidence of endometriosis has been reported and coincides with the introduction of genetically modified foods in our diet. Even though assessments of genetically modified food risk have not indicated any hazard on human health, xenobiotics-associated genetically modified food, such as pesticides residues and xenoproteins, could be harmful in the long-term. The "low-dose hypothesis", accumulation and biotransformation of pesticides-associated genetically modified food and the multiplied toxicity of pesticides-formulation adjuvants support this hypothesis. This review summarizes toxic effects (in vitro and on animal models) of some xenobiotics-associated genetically modified food, such as glyphosate and Cry1Ab protein, and extrapolates on their potential role in the pathophysiology of endometriosis. Their roles as immune toxicants, pro-oxidants, endocrine disruptors and epigenetic modulators are discussed. PMID:21111655

Aris, A; Paris, K

2010-12-01

390

Thirteen week feeding study with transgenic maize grain containing event DAS-Ø15Ø7-1 in Sprague–Dawley rats  

Microsoft Academic Search

Maize line 1507, containing event DAS-Ø15Ø7-1 (1507), is a genetically modified (GM) maize plant that expresses the cry1F gene from Bacillus thuringiensis (Bt) sbsp. aizawai and the phosphinothricin-N-acetyltransferase (pat) gene from Streptomyces viridochromogenes throughout the plant including in the grain expression of the Cry1F protein confers in planta resistance to the European corn borer (ECB; Ostrinia nubilalis Hübner: Crambidae) and

Susan A. MacKenzie; Ian Lamb; Jean Schmidt; Lora Deege; Michael J. Morrisey; Marc Harper; Raymond J. Layton; Lee M. Prochaska; Craig Sanders; Mary Locke; Joel L. Mattsson; Angel Fuentes; Bryan Delaney

2007-01-01

391

Systemic delivery of recombinant proteins by genetically modified myoblasts  

SciTech Connect

The ability to stably deliver recombinant proteins to the systemic circulation would facilitate the treatment of a variety of acquired and inherited diseases. To explore the feasibility of the use of genetically engineered myoblasts as a recombinant protein delivery system, stable transfectants of the murine C2C12 myoblast cell line were produced that synthesize and secrete high levels of human growth hormone (hGH) in vitro. Mice injected with hGH-transfected myoblasts had significant levels of hGH in both muscle and serum that were stable for at least 3 weeks after injection. Histological examination of muscles injected with {beta}-galactosidase-expressing C2C12 myoblasts demonstrated that many of the injected cells had fused to form multinucleated myotubes. Thus, genetically engineered myoblasts can be used for the stable delivery of recombinant proteins into the circulation.

Barr, E.; Leiden, J.M. (Univ. of Michigan, Ann Arbor (United States))

1991-12-06

392

Genetically Modified Food: GM Crops: Time to Choose  

NSDL National Science Digital Library

As this Nature Web focus explains, "just four countries account for 99% of the world's commercially grown transgenic crops," and other countries "have been stalling over whether to embrace transgenic agriculture, but won't be able to put off the decision for much longer." Readers can get an in-depth look at this issue with free features from Nature, including recent news articles, an interactive map of the world, and a link to Nature Reviews Genetics_ (also free of charge).

393

Exploitation of genetically modified inoculants for industrial ecology applications  

Microsoft Academic Search

The major growth seen in the biotechnology industry in recent decades has largely been driven by the exploitation of genetic\\u000a engineering techniques. The initial benefits have been predominantly in the biomedical area, with products such as vaccines\\u000a and hormones that have received broad public approval. In the environmental biotechnology and industrial ecology sectors,\\u000a biotechnology has the potential to make significant

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

2002-01-01

394

Bridging Traditional and Molecular Genetics in Modifying Cottonseed Oil  

Microsoft Academic Search

Cotton breeding has traditionally focused on improving crop productivity and fiber quality. While this is still the major\\u000a objective, there is increased interest in improving the nutritional and functional properties of the cotton seed oil. The\\u000a nutritional and industrial value of cottonseed oil, like other vegetable oils, is determined by its fatty acid profile. Conventional\\u000a genetics and breeding approaches to

Qing Liu; Surinder Singh; Kent Chapman; Allan Green

395

Zeaxanthin is bioavailable from genetically modified zeaxanthin-rich potatoes  

Microsoft Academic Search

The carotenoid zeaxanthin accumulates in the human macula lutea and protects retinal cells from blue light damage. However,\\u000a zeaxanthin intake from food sources is low. Increasing zeaxanthin in common foods such as potatoes by traditional plant breeding\\u000a or by genetic engineering could contribute to an increased intake of this carotenoid and, consequently, to a decreased risk\\u000a of age-related macular degeneration.

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

2008-01-01

396

Genetic and environmental modifiers of Alzheimer's disease phenotypes in the mouse.  

PubMed

As a group, strains of laboratory mice carrying Alzheimer's disease (AD)-related transgenes are currently the most widely studied animal models of AD. Many AD mouse models carrying the same or similar transgene constructs demonstrate strikingly different phenotypic responses to transgene expression, mimicking the apparent genetic complexity of AD pathogenesis seen in the human population. Genetic differences between the numerous mouse model strains used for AD research can significantly affect correct interpretation and cross-comparison of experimental findings, making genetic background an important consideration for all work in mouse models of AD. Furthermore, because of the potential for discovering novel genetic modifiers of AD pathogenesis, the effects of genetic background on AD phenotypes in the mouse can prove a worthwhile subject of study in their own right. This review discusses the implications of genetic modifiers for mouse and human AD research, and summarizes recent findings identifying significant roles for genetic background in modifying important phenotypes in AD mouse models, including premature death, amyloid deposition, tau hyperphosphorylation, and responsiveness to environmental or treatment interventions. PMID:17168645

Ryman, Davis; Lamb, Bruce T

2006-12-01

397

Safety assessment, detection and traceability, and societal aspects of genetically modified foods. European Network on Safety Assessment of Genetically Modified Food Crops (ENTRANSFOOD). Concluding remarks.  

PubMed

The most important results from the EU-sponsored ENTRANSFOOD Thematic Network project are reviewed, including the design of a detailed step-wise procedure for the risk assessment of foods derived from genetically modified crops based on the latest scientific developments, evaluation of topical risk assessment issues, and the formulation of proposals for improved risk management and public involvement in the risk analysis process. PMID:15123387

Kuiper, H A; König, A; Kleter, G A; Hammes, W P; Knudsen, I

2004-07-01

398

New trends in bioanalytical tools for the detection of genetically modified organisms: an update  

Microsoft Academic Search

Despite the controversies surrounding genetically modified organisms (GMOs), the production of GM crops is increasing, especially\\u000a in developing countries. Thanks to new technologies involving genetic engineering and unprecedented access to genomic resources,\\u000a the next decade will certainly see exponential growth in GMO production. Indeed, EU regulations based on the precautionary\\u000a principle require any food containing more than 0.9% GM content

Elisa Michelini; Patrizia Simoni; Luca Cevenini; Laura Mezzanotte; Aldo Roda

2008-01-01

399

A Precautionary Approach to Genetically Modified Organisms: Challenges and Implications for Policy and Science  

Microsoft Academic Search

The commercial introduction of genetically modified organisms (GMOs) has revealed a broad range of views among scientists\\u000a and other stakeholders on perspectives of genetic engineering (GE) and if and how GMOs should be regulated. Within this controversy,\\u000a the precautionary principle has become a contentious issue with high support from skeptical groups but resisted by GMO advocates.\\u000a How to handle lack

Anne Ingeborg Myhr

2010-01-01

400

Advances in molecular techniques for the detection and quantification of genetically modified organisms  

Microsoft Academic Search

Progress in genetic engineering has led to the introduction of genetically modified organisms (GMOs) whose genomes have been\\u000a altered by the integration of a novel sequence conferring a new trait. To allow consumers an informed choice, many countries\\u000a require food products to be labeled if the GMO content exceeds a certain threshold. Consequently, the development of analytical\\u000a methods for GMO

Dimitrios S. Elenis; Despina P. Kalogianni; Kyriaki Glynou; Penelope C. Ioannou; Theodore K. Christopoulos

2008-01-01

401

A PCR-microarray method for the screening of genetically modified organisms  

Microsoft Academic Search

A new method to screen and to identify genetically modified organisms (GMO) is presented in this paper. It is based on the\\u000a detection of multiple genetic elements common to GMO by their amplification via PCR followed by direct hybridisation of the\\u000a amplicons on microarray. The pattern of the elements is then compared to a database of the composition of EU-approved

Sandrine Hamels; Thomas Glouden; Karine Gillard; Marco Mazzara; Frédéric Debode; Nicoletta Foti; Myriam Sneyers; Teresa Esteve Nuez; Maria Pla; Gilbert Berben; William Moens; Yves Bertheau; Colette Audéon; Guy Van den Eede; José Remacle

2009-01-01

402

Effect of diets containing genetically modified potatoes expressing Galanthus nivalis lectin on rat small intestine.  

PubMed

Diets containing genetically modified (GM) potatoes expressing the lectin Galanthus nivalis agglutinin (GNA) had variable effects on different parts of the rat gastrointestinal tract. Some effects, such as the proliferation of the gastric mucosa, were mainly due to the expression of the GNA transgene. However, other parts of the construct or the genetic transformation (or both) could also have contributed to the overall biological effects of the GNA-GM potatoes, particularly on the small intestine and caecum. PMID:10533866

Ewen, S W; Pusztai, A

1999-10-16

403

Genetically modified wine yeasts and risk assessment studies covering different steps within the wine making process  

Microsoft Academic Search

The use of gene technology to modify the genome of wine yeasts belonging to the species Saccharomyces cerevisiae began in the early 1990s. From a purely scientific point of view, many yeast constructs [genetically modified organisms (GMO)]\\u000a have been made so far, covering more or less all stages of the wine making process in which microorganisms or commercial enzymes\\u000a play

Manfred Grossmann; Falk Kießling; Julian Singer; Heidi Schoeman; Max-Bernd Schröder; Christian von Wallbrunn

2011-01-01

404

Real-time polymerase chain reaction detection of cauliflower mosaic virus to complement the 35S screening assay for genetically modified organisms.  

PubMed

Labeling of genetically modified organisms (GMOs) is now in place in many countries, including the European Union, in order to guarantee the consumer's choice between GM and non-GM products. Screening of samples is performed by polymerase chain reaction (PCR) amplification of regulatory sequences frequently introduced into genetically modified plants. Primers for the 35S promoter from Cauliflower mosaic virus (CaMV) are those most frequently used. In virus-infected plants or in samples contaminated with plant material carrying the virus, false-positive results can consequently occur. A system for real-time PCR using a TaqMan minor groove binder probe was designed that allows recognition of virus coat protein in the sample, thus allowing differentiation between transgenic and virus-infected samples. We measured the efficiency of PCR amplification, limits of detection and quantification, range of linearity, and repeatability of the assay in order to assess the applicability of the assay for routine analysis. The specificity of the detection system was tested on various virus isolates and plant species. All 8 CaMV isolates were successfully amplified using the designed system. No cross-reactivity was detected with DNA from 3 isolates of the closely related Carnation etched ring virus. Primers do not amplify plant DNA from available genetically modified maize and soybean lines or from different species of Brassicaceae or Solanaceae that are natural hosts for CaMV. We evaluated the assay for different food matrixes by spiking CaMV DNA into DNA from food samples and have successfully amplified CaMV from all samples. The assay was tested on rapeseed samples from routine GMO testing that were positive in the 35S screening assay, and the presence of the virus was confirmed. PMID:16001857

Cankar, Katarina; Ravnikar, Maja; Zel, Jana; Gruden, Kristina; Toplak, Natasa

2005-01-01

405

Characterization of five microRNA families in maize.  

PubMed

In recent years, microRNAs (miRNAs) have polarized the interest of the scientific community as a new category of gene expression regulators, present in both plants and animals. Plant miRNAs are involved in processes such as plant development, organ identity, and stress response. Nonetheless, knowledge of their functions is still incomplete, and it is conceivable that further new processes in which they are involved will be discovered. For these reasons, structural and functional characterization of MIR genes, that are also in crop species such as Zea mays L., becomes instrumental in addressing genetic and molecular mechanisms controlling phenotype determination and phenotypic adaptation to growing conditions. The present study contributes to the characterization of five miRNA families in maize, from the determination of their expression pattern in different maize tissues and genotypes, to the identification of putative targets by bioinformatic means and subsequent experimental validation of three targets by modified 5' RACE experiments. Furthermore, 30 different MIR genes belonging to these five miRNA families were analysed by their attribution to maize chromosomes using oat-maize addition lines and by investigating their phylogenetic relationship with genes from other cereals. In particular, sequence homology was determined by the reciprocal best BLAST hit approach, to define groups of homologous genes between maize, rice, and sorghum. PMID:16820394

Mica, Erica; Gianfranceschi, Luca; Pè, Mario Enrico

2006-01-01

406

Individual Maize Chromosomes in the C3 Plant Oat Can Increase Bundle Sheath Cell Size and Vein Density1[W][OA  

PubMed Central

C4 photosynthesis has evolved in at least 66 lineages within the angiosperms and involves alterations to the biochemistry, cell biology, and development of leaves. The characteristic “Kranz” anatomy of most C4 leaves was discovered in the 1890s, but the genetic basis of these traits remains poorly defined. Oat × maize addition lines allow the effects of individual maize (Zea mays; C4) chromosomes to be investigated in an oat (Avena sativa; C3) genetic background. Here, we have determined the extent to which maize chromosomes can introduce C4 characteristics into oat and have associated any C4-like changes with specific maize chromosomes. While there is no indication of a simultaneous change to C4 biochemistry, leaf anatomy, and ultrastructure in any of the oat × maize addition lines, the C3 oat leaf can be modified at multiple levels. Maize genes encoding phosphoenolpyruvate carboxylase, pyruvate, orthophosphate dikinase, and the 2?-oxoglutarate/malate transporter are expressed in oat and generate transcripts of the correct size. Three maize chromosomes independently cause increases in vein density, and maize chromosome 3 results in larger bundle sheath cells with increased cell wall lipid deposition in oat leaves. These data provide proof of principle that aspects of C4 biology could be integrated into leaves of C3 crops.

Tolley, Ben J.; Sage, Tammy L.; Langdale, Jane A.; Hibberd, Julian M.

2012-01-01

407

Modulation of gut-associated lymphoid tissue functions with genetically modified Lactococcus lactis.  

PubMed

Lactic acid bacteria are a group of taxonomically diverse, Gram-positive food-grade bacteria that have been safely consumed throughout history. The lactic acid bacterium Lactococcus lactis, well-known for its use in the manufacture of cheese, can be genetically engineered and orally formulated to deliver therapeutic proteins in the gastrointestinal tract. This review focuses on the genetic engineering of Lactococcus lactis to secrete high-quality, correctly processed bioactive molecules derived from a eukaryotic background. The therapeutic applications of these genetically modified strains are discussed, with special regards to immunomodulation. PMID:19954359

Rottiers, Pieter; De Smedt, Tim; Steidler, Lothar

2009-01-01

408

Genetically Modified Plants: What’s the Fuss? (402nd Brookhaven Lecture)  

SciTech Connect

Genetic transformation is a relatively new and powerful tool used by plant breeders and for basic research. Benefits of gene transformation include resistance to pests and herbicides, which has led to a reduction in pesticide application and soil erosion. Genetically modified plants are used on a massive scale in agriculture in the U.S. and other countries, in part because they are less expensive and more convenient to work with. Yet, despite the benefits, genetic transformation remains a controversial subject and groups in the U.S. and abroad contest its practice.

Burr, Ben (Senior Geneticist, BNL Biology Dept) [Senior Geneticist, BNL Biology Dept

2006-03-16

409

Genetic Rearrangements Can Modify Chromatin Features at Epialleles  

PubMed Central

Analogous to genetically distinct alleles, epialleles represent heritable states of different gene expression from sequence-identical genes. Alleles and epialleles both contribute to phenotypic heterogeneity. While alleles originate from mutation and recombination, the source of epialleles is less well understood. We analyze active and inactive epialleles that were found at a transgenic insert with a selectable marker gene in Arabidopsis. Both converse expression states are stably transmitted to progeny. The silent epiallele was previously shown to change its state upon loss-of-function of trans-acting regulators and drug treatments. We analyzed the composition of the epialleles, their chromatin features, their nuclear localization, transcripts, and homologous small RNA. After mutagenesis by T-DNA transformation of plants carrying the silent epiallele, we found new active alleles. These switches were associated with different, larger or smaller, and non-overlapping deletions or rearrangements in the 3? regions of the epiallele. These cis-mutations caused different degrees of gene expression stability depending on the nature of the sequence alteration, the consequences for transcription and transcripts, and the resulting chromatin organization upstream. This illustrates a tight dependence of epigenetic regulation on local structures and indicates that sequence alterations can cause epigenetic changes at some distance in regions not directly affected by the mutation. Similar effects may also be involved in gene expression and chromatin changes in the vicinity of transposon insertions or excisions, recombination events, or DNA repair processes and could contribute to the origin of new epialleles.

Foerster, Andrea M.; Dinh, Huy Q.; Sedman, Laura; Wohlrab, Bonnie; Mittelsten Scheid, Ortrun

2011-01-01

410

[Medico-genetic evaluation of sugar sand, obtained from genetically-modified sugar beet line 77 (toxicologico-biochemical studies)].  

PubMed

The rats were fed with the Suger from the Genetically Modified Suger Beet line 77 (Monsanto Ko, USA) 3 g/rat/day for 3 months. Their blood, urea and liver were investigated to measure total protein and glucose levels, aminotransferase and alkaline phosphatase activities, pH, creatinine level as well as hepatic enzyme activity of the I and II phases of henobiotic metabolism and whole and non-sedimentated lysosomal enzyme activities and activity of antioxidant system. PMID:12227014

Kravchenko, L V; Sorokina, E Iu; Tyshko, N V; Chernysheva, O N; Avren'eva, L I; Guseva, G V

2002-01-01

411

Immunodiagnostic analysis of transgenic vegetative insecticidal protein in genetically modified crops\\/produce  

Microsoft Academic Search

In the process of development of insect resistant genetically modified (GM) crops and also to evaluate the consistency in the expression of toxin under field conditions, immunological assays are commonly being used. We have developed immunoassay to support labelling of vegetative insecticidal protein (Vip3A) based GM produce. The developed ELISA for measurement of Vip3A is a triple antibody sandwich procedure

Chandra K. Singh; Rajesh Kumar; Rajeshwar P. Sinha; Prakash C. Misra

2011-01-01

412

GENETICALLY MODIFIED FOOD CROPS AND PUBLIC HEALTH Cultivos alimenticios genéticamente modificados y salud pública  

Microsoft Academic Search

The progress made in plant biotechnology has provided an opportunity to new food crops being developed having desirable traits for improving crop yield, reducing the use of agrochemicals and adding nutritional properties to staple crops. However, genetically modified (GM) crops have become a subject of intense debate in which opponents argue that GM crops represent a threat to individual freedom,

ORLANDO ACOSTA

413

Sustained Delivery of Erythropoietin in Mice by Genetically Modified Skin Fibroblasts  

Microsoft Academic Search

We have examined whether the secretion of erythropoietin (Epo) from genetically modified cells could represent an alternative to repeated injections of the recombinant hormone for treating chronic anemias responsive to Epo. Primary mouse skin fibroblasts were transduced with a retroviral vector in which the murine Epo cDNA is expressed under the control of the murine phosphoglycerate kinase promoter. \\

N. Naffakh; A. Henri; J. L. Villeval; P. Rouyer-Fessard; P. Moullier; N. Blumenfeld; O. Danos; W. Vainchenker; J. M. Heard; Y. Beuzard

1995-01-01

414

An introduction to the Farm-Scale Evaluations of genetically modified herbicide-tolerant crops  

Microsoft Academic Search

Summary 1. Several genetically modified herbicide-tolerant (GMHT) crops have cleared most of the regulatory hurdles required for commercial growing in the United Kingdom. However, concerns have been expressed that their management will have negative impacts on farmland biodiversity as a result of improved control given by the new herbicide regimes of the arable plants that support farmland birds and other

L. G. Firbank; M. S. Heard; I. P. Woiwod; C. Hawes; A. J. Haughton; G. T. Champion; R. J. Scott; M. O. Hill; A. M. Dewar; G. R. Squire; M. J. May; D. R. Brooks; D. A. Bohan; R. E. Daniels; J. L. Osborne; D. B. Roy; H. I. J. Black; P. Rothery; J. N. Perry

2003-01-01

415

A novel approach to the use of genetically modified herbicide tolerant crops for environmental benefit  

Microsoft Academic Search

The proposed introduction of genetically modified herbicide tolerant (GMHT) crops, with claims of improved weed control, has prompted fears about possible environmental impacts of their widespread adoption, particularly on arable weeds, insects and associated farmland birds. In response to this, we have developed a novel weed-management system for GMHT sugar beet, based on band spraying, which exploits the flexibility offered

Alan M. Dewar; Mike J. May; Ian P. Woiwod; Lisa A. Haylock; Gillian T. Champion; Beulah H. Garner; Richard J. N. Sands; Aiming Qi; John D. Pidgeon

2003-01-01

416

Genetically Modified Rice, Yields, and Pesticides: Assessing Farm-Level Productivity Effects in China  

Microsoft Academic Search

Although genetically modified (GM) crops are being grown on increasing large areas in both developed and developing countries, with few minor exceptions, there has been almost no country that has commercialized a GM major food crop. One reason may be that it is unclear how the commercialization of GM crops will help poor, small farmers. The objective of this article

Jikun Huang; Ruifa Hu; Scott Rozelle; Carl Pray

2008-01-01

417

Labeling genetically modified food in India: Economic consequences in four marketing channels  

Microsoft Academic Search

In 2006, India proposed a draft rule requiring the labeling of all genetically modified (GM) foods and products derived thereof. In this paper, we use primary and secondary market data to assess the economic implications of introducing such a mandatory labeling policy for GM food. We focus on four products that would likely be the first affected by such a

Sangeeta Bansal; Guillaume Gruère

2010-01-01

418

Degradation of transgene DNA in genetically modified herbicide-tolerant rice during food processing  

Microsoft Academic Search

In order to assess the effect of food processing on the degradation of exogenous DNA components in sweet rice wine and rice crackers made from genetically modified (GM) rice (Oryza sativa L.), we developed genomic DNA extraction methods and compared the effect of different food processing procedures on DNA degradation. It was found that the purity, quantity and quality of

Shangxin Song; Guanghong Zhou; Feng Gao; Wei Zhang; Liangyan Qiu; Sifa Dai; Xinglian Xu; Hongmei Xiao

2011-01-01

419

Quantitative analysis of genetically modified organisms (GMO) in processed food by PCR-based methods  

Microsoft Academic Search

Two different PCR-based approaches for the quantitative analysis of genetically modified organism (GMO) – components in foods are presented using Soybean derived samples as an example. The first method – a double competitive PCR – is well suited to determine threshold levels of GMO content in food. The other – PCR on-line measurement – is suited to determine ratios of

A. Wurz; A. Bluth; P. Zeltz; C. Pfeifer; R. Willmund

1999-01-01

420

PCR technology for screening and quantification of genetically modified organisms (GMOs)  

Microsoft Academic Search

Although PCR technology has obvious limitations, the potentially high degree of sensitivity and specificity explains why it has been the first choice of most analytical laboratories interested in detection of genetically modified (GM) organisms (GMOs) and derived materials. Because the products that laboratories receive for analysis are often processed and refined, the qua