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2.
Plant Physiol ; 190(3): 1579-1587, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-35976141

RESUMO

A decade ago, the CRISPR/Cas system has been adapted for genome editing. Since then, hundreds of organisms have been altered using genome editing and discussions were raised on the regulatory status of genome edited organisms esp. crops. To date, many countries have made decisions on the regulatory status of products of genome editing, by exempting some kinds of edits from the classical GMO regulation. However, the guidance differs between countries even in the same region. Several countries are still debating the issue or are in the progress of updating guidance and regulatory systems to cover products of genome editing. The current global situation of different regulatory systems is putting a harmonized framework on genome-edited crops in the far future. In this update, we summarize the current developments in the field of regulation concerning edited crops and present a short insight into perception of genome editing in the society.


Assuntos
Edição de Genes , Genoma de Planta , Genoma de Planta/genética , Sistemas CRISPR-Cas/genética , Produtos Agrícolas/genética , Políticas
3.
Biology (Basel) ; 10(7)2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34356545

RESUMO

The realization of the full objectives of international policies targeting global food security and climate change mitigation, including the United Nation's Sustainable Development Goals, the Paris Climate Agreement COP21 and the European Green Deal, requires that we (i) sustainably increase the yield, nutritional quality and biodiversity of major crop species, (ii) select climate-ready crops that are adapted to future weather dynamic and (iii) increase the resource use efficiency of crops for sustainably preserving natural resources. Ultimately, the grand challenge to be met by agriculture is to sustainably provide access to sufficient, nutritious and diverse food to a worldwide growing population, and to support the circular bio-based economy. Future-proofing our crops is an urgent issue and a challenging goal, involving a diversity of crop species in differing agricultural regimes and under multiple environmental drivers, providing versatile crop-breeding solutions within wider socio-economic-ecological systems. This goal can only be realized by a large-scale, international research cooperation. We call for international action and propose a pan-European research initiative, the CropBooster Program, to mobilize the European plant research community and interconnect it with the interdisciplinary expertise necessary to face the challenge.

4.
Front Plant Sci ; 11: 574959, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329634

RESUMO

CRISPR/Cas enables a targeted modification of DNA sequences. Despite their ease and efficient use, one limitation is the potential occurrence of associated off-target effects. This systematic review aims to answer the following research question: Which factors affect the occurrence of off-target effects caused by the use of CRISPR/Cas in plants? Literature published until March 2019 was considered for this review. Articles were screened for relevance based on pre-defined inclusion criteria. Relevant studies were subject to critical appraisal. All studies included in the systematic review were synthesized in a narrative report, but studies rated as high and medium/high validity were reported separately from studies rated as low and medium/low or unclear validity. In addition, we ran a binary logistic regression analysis to verify five factors that may affect the occurrence of off-target effects: (1) Number of mismatches (2) Position of mismatches (3) GC-content of the targeting sequence (4) Altered nuclease variants (5) Delivery methods. In total, 180 relevant articles were included in this review containing 468 studies therein. Seventy nine percentage of these studies were rated as having high or medium/high validity. Within these studies, 6,416 potential off-target sequences were assessed for the occurrence of off-target effects. Results clearly indicate that an increased number of mismatches between the on-target and potential off-target sequence steeply decreases the likelihood of off-target effects. The observed rate of off-target effects decreased from 59% when there is one mismatch between the on-target and off-target sequences toward 0% when four or more mismatches exist. In addition, mismatch/es located within the first eight nucleotides proximal to the PAM significantly decreased the occurrence of off-target effects. There is no evidence that the GC-content significantly affects off-target effects. The database regarding the impact of the nuclease variant and the delivery method is very poor as the majority of studies applied the standard nuclease SpCas9 and the CRISPR/Cas system was stably delivered in the genome. Hence, a general significant impact of these two factors on the occurrence of off-target effects cannot be proved. This identified evidence gap needs to be filled by systematic studies exploring these individual factors in sufficient numbers.

5.
Front Plant Sci ; 11: 586027, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33163013

RESUMO

Products of genome editing as the most promising "New Plant Breeding Technology" (NPBT) have made the transition from the lab to the market in a short time. Globally, research activities employing genome editing are constantly expanding and more and more plants with market-oriented traits are being developed, and companies have already released the first genome edited crops to the market. Few countries, most of which are located in the Americas, have adapted legislations to these technologies or released guidelines supporting the use of genome editing. Other countries are debating the path to come either because there is no clarity on the legal classification or due consensus is hampered by a renewed GMO debate. In recent years (2017-2020), eight countries have introduced guidelines clarifying the legal status of genome edited products and many of those are actively committed to international harmonization of their policies. In this publication we give an overview on the current and potentially future international regulatory environment and an update on plants derived by genome editing with market-oriented traits.

6.
Front Plant Sci ; 11: 584485, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33014005

RESUMO

The European Commission has asked EU Member States for comments on a French law notification demanding plant varieties produced with the help of in vitro mutagenesis have to be eliminated from the national catalog of approved varieties because of missing legal authorization deemed required by genetic engineering law. Primary target are herbicide-tolerant Clearfield oilseed rape varieties. The scientific reasoning is questionable, traceability is illusive, and law enforcement is likely to be impossible.

9.
Front Plant Sci ; 10: 236, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30930911

RESUMO

Conventional genetic engineering techniques generate modifications in the genome via stable integration of DNA elements which do not occur naturally in this combination. Therefore, the resulting organisms and (most) products thereof can unambiguously be identified with event-specific PCR-based methods targeting the insertion site. New breeding techniques such as genome editing diversify the toolbox to generate genetic variability in plants. Several of these techniques can introduce single nucleotide changes without integrating foreign DNA and thereby generate organisms with intended phenotypes. Consequently, such organisms and products thereof might be indistinguishable from naturally occurring or conventionally bred counterparts with established analytical tools. The modifications can entirely resemble random mutations regardless of being spontaneous or induced chemically or via irradiation. Therefore, if an identification of these organisms or products thereof is demanded, a new challenge will arise for (official) seed, food, and feed testing laboratories and enforcement institutions. For detailed consideration, we distinguish between the detection of sequence alterations - regardless of their origin - the identification of the process that generated a specific modification and the identification of a genotype, i.e., an organism produced by genome editing carrying a specific genetic alteration in a known background. This article briefly reviews the existing and upcoming detection and identification strategies (including the use of bioinformatics and statistical approaches) in particular for plants developed with genome editing techniques.

10.
Arch Toxicol ; 93(4): 1095-1139, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30756133

RESUMO

In 2012, a controversial study on the long-term toxicity of a Roundup herbicide and the glyphosate-tolerant genetically modified (GM) maize NK603 was published. The EC-funded G-TwYST research consortium tested the potential subchronic and chronic toxicity as well as the carcinogenicity of the glyphosate-resistant genetically modified maize NK603 by performing two 90-day feeding trials, one with GM maize inclusion rates of 11 and 33% and one with inclusion rates of up to 50%, as well as a 2-year feeding trial with inclusion rates of 11 and 33% in male and female Wistar Han RCC rats by taking into account OECD Guidelines for the testing of chemicals and EFSA recommendations on the safety testing of whole-food/feed in laboratory animals. In all three trials, the NK603 maize, untreated and treated once with Roundup during its cultivation, and the conventional counterpart were tested. Differences between each test group and the control group were evaluated. Equivalence was assessed by comparing the observed difference to differences between non-GM reference groups in previous studies. In case of significant differences, whether the effects were dose-related and/or accompanied by changes in related parameters including histopathological findings was evaluated. It is concluded that no adverse effects related to the feeding of the NK603 maize cultivated with or without Roundup for up to 2 years were observed. Based on the outcome of the subchronic and combined chronic toxicity/carcinogenicity studies, recommendations on the scientific justification and added value of long-term feeding trials in the GM plant risk assessment process are presented.


Assuntos
Ração Animal/normas , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Alimentos Geneticamente Modificados , Glicina/análogos & derivados , Herbicidas/toxicidade , Plantas Geneticamente Modificadas/efeitos dos fármacos , Zea mays , Animais , Testes de Carcinogenicidade , Resistência a Medicamentos/genética , Feminino , Glicina/toxicidade , Masculino , Plantas Geneticamente Modificadas/genética , Ratos Wistar , Testes de Toxicidade Crônica , Testes de Toxicidade Subcrônica , Zea mays/efeitos dos fármacos , Zea mays/genética , Glifosato
11.
Arch Toxicol ; 92(7): 2385-2399, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29855658

RESUMO

The genetically modified maize event MON810 expresses a Bacillus thuringiensis-derived gene, which encodes the insecticidal protein Cry1Ab to control some lepidopteran insect pests such as the European corn borer. It has been claimed that the immune system may be affected following the oral/intragastric administration of the MON810 maize in various different animal species. In the frame of the EU-funded project GRACE, two 90-day feeding trials, the so-called studies D and E, were performed to analyze the humoral and cellular immune responses of male and female Wistar Han RCC rats fed the MON810 maize. A MON810 maize variety of Monsanto was used in the study D and a MON810 maize variety of Pioneer Hi-Bred was used in the study E. The total as well as the maize protein- and Cry1Ab-serum-specific IgG, IgM, IgA and IgE levels, the proliferative activity of the lymphocytes, the phagocytic activity of the granulocytes and monocytes, the respiratory burst of the phagocytes, a phenotypic analysis of spleen, thymus and lymph node cells as well as the in vitro production of cytokines by spleen cells were analyzed. No specific Cry1Ab immune response was observed in MON810 rats, and anti-maize protein antibody responses were similar in MON810 and control rats. Single parameters were sporadically altered in rats fed the MON810 maize when compared to control rats, but these alterations are considered to be of no immunotoxicological significance.


Assuntos
Ração Animal/toxicidade , Alimentos Geneticamente Modificados/toxicidade , Imunidade Celular , Imunidade Humoral , Plantas Geneticamente Modificadas/toxicidade , Zea mays/genética , Ração Animal/normas , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/imunologia , Qualidade de Produtos para o Consumidor , Endotoxinas/imunologia , Hipersensibilidade Alimentar/imunologia , Alimentos Geneticamente Modificados/normas , Proteínas Hemolisinas/imunologia , Imunoglobulinas/sangue , Plantas Geneticamente Modificadas/imunologia , Ratos Wistar , Testes de Toxicidade Crônica
12.
Arch Toxicol ; 91(4): 1977-2006, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27730258

RESUMO

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


Assuntos
Alimentos Geneticamente Modificados/toxicidade , Plantas Geneticamente Modificadas/toxicidade , Zea mays/genética , Ração Animal , Animais , Peso Corporal , Feminino , Modelos Lineares , Masculino , Tamanho do Órgão , Ratos , Ratos Wistar , Fatores de Tempo , Testes de Toxicidade/métodos
14.
Arch Toxicol ; 90(10): 2531-62, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27439414

RESUMO

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


Assuntos
Ração Animal , Alimentos Geneticamente Modificados/toxicidade , Nível de Saúde , Plantas Geneticamente Modificadas/toxicidade , Zea mays/genética , Ração Animal/normas , Ração Animal/toxicidade , Animais , Feminino , Masculino , Ratos Endogâmicos , Medição de Risco , Testes de Toxicidade Crônica
16.
Arch Toxicol ; 90(3): 731-51, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25724152

RESUMO

In this paper, we compare the traditional ANOVA approach to analysing data from 90-day toxicity studies with a more modern LMM approach, and we investigate the use of standardized effect sizes. The LMM approach is used to analyse weight or feed consumption data. When compared to the week-by-week ANOVA with multiple test results per week, this approach results in only one statement on differences in weight development between groups. Standardized effect sizes are calculated for the endpoints: weight, relative organ weights, haematology and clinical biochemistry. The endpoints are standardized, allowing different endpoints of the same study to be compared and providing an overall picture of group differences at a glance. Furthermore, in terms of standardized effect sizes, statistical significance and biological relevance are displayed simultaneously in a graph.


Assuntos
Modelos Lineares , Testes de Toxicidade/métodos , Testes de Toxicidade/normas , Toxicologia/estatística & dados numéricos , Análise de Variância , Animais , Peso Corporal , Masculino , Tamanho do Órgão , Plantas Geneticamente Modificadas , Ratos , Testes de Toxicidade/estatística & dados numéricos , Toxicologia/normas , Zea mays
17.
Artigo em Inglês | MEDLINE | ID: mdl-26322307

RESUMO

Systematic reviews represent powerful tools to identify, collect, synthesize, and evaluate primary research data on specific research questions in a highly standardized and reproducible manner. They enable the defensible synthesis of outcomes by increasing precision and minimizing bias whilst ensuring transparency of the methods used. This makes them especially valuable to inform evidence-based risk analysis and decision making in various topics and research disciplines. Although seen as a "gold standard" for synthesizing primary research data, systematic reviews are not without limitations as they are often cost, labor and time intensive and the utility of synthesis outcomes depends upon the availability of sufficient and robust primary research data. In this paper, we (1) consider the added value systematic reviews could provide when synthesizing primary research data on genetically modified organisms (GMO) and (2) critically assess the adequacy and feasibility of systematic review for collating and analyzing data on potential impacts of GMOs in order to better inform specific steps within GMO risk assessment and risk management. The regulatory framework of the EU is used as an example, although the issues we discuss are likely to be more widely applicable.

18.
Arch Toxicol ; 88(12): 2289-314, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25270621

RESUMO

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


Assuntos
Ração Animal , Alimentos Geneticamente Modificados/toxicidade , Plantas Geneticamente Modificadas/toxicidade , Zea mays/genética , Administração Oral , Ração Animal/normas , Ração Animal/toxicidade , Animais , Peso Corporal , Qualidade de Produtos para o Consumidor , Dieta , Feminino , Masculino , Tamanho do Órgão , Ratos Endogâmicos , Projetos de Pesquisa , Medição de Risco , Testes de Toxicidade Subcrônica
19.
Opt Express ; 18(12): 13094-101, 2010 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-20588439

RESUMO

The onset of parasitic oscillations limits the extraction efficiency and therefore energy scaling of Q-switched lasers. A solid-state laser was end pumped with a fiber-coupled diode laser and operated in q-cw as well as in passively Q-switched operation. For Q-switched operation, we demonstrate the suppression of parasitic oscillations in a core-doped ceramic Nd:YAG laser by Sm:YAG cladding.

20.
Appl Opt ; 49(5): 811-6, 2010 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-20154747

RESUMO

We report on a compact Nd:YAG amplifier emitting a maximum pulse energy of 14 mJ. By amplifying a passively Q-switched oscillator (M(2)<1.2) a good beam quality of M(2) approximately 1.7 was achieved. The amplifier is diode pumped by an 8 bar diode stack of 800 W power and a nonimaging optic. This optic homogenizes the pump light and transfers it into a 5 mm diameter core doped rod with a centrally neodymium doped region of 3 mm and a samarium doped YAG cladding. We show that this cladding reduces parasitic effects in the laser rod compared to an undoped YAG cladding. Finally, we compare the compact amplifier with an amplifier, which is mode selectively pumped by a fiber coupled pump diode.

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