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PubMed2003

Genetically modified probiotics in foods.

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.

Animals↗
PubMedDate not supplied

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

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.

DNA, Plant↗
PubMed2004

DNA microarray technology in nutraceutical and food safety.

The quality and quantity of diet is a key determinant of health and disease. Molecular diagnostics may play a key role in food safety related to genetically modified foods, food-borne pathogens and novel nutraceuticals. Functional outcomes in biology are determined, for the most part, by net balance between sets of genes related to the specific outcome in question. The DNA microarray technology offers a new dimension of strength in molecular diagnostics by permitting the simultaneous analysis of large sets of genes. Automation of assay and novel bioinformatics tools make DNA microarrays a robust technology for diagnostics. Since its development a few years ago, this technology has been used for the applications of toxicogenomics, pharmacogenomics, cell biology, and clinical investigations addressing the prevention and intervention of diseases. Optimization of this technology to specifically address food safety is a vast resource that remains to be mined. Efforts to develop diagnostic custom arrays and simplified bioinformatics tools for field use are warranted.

Animals↗
PubMed2002

Detection of genetically modified organisms in foods.

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 sequences is not available, new approaches, such as near-infrared spectrometry, might tackle the problem of detection of non-approved genetically modified (GM) foods. The efficiency of screening, identification and confirmation strategies should be examined with respect to false-positive rates, disappearance of marker genes, increased use of specific regulator sequences and the increasing number of GM foods.

Blotting, Southern↗
PubMed1999

The safety and social acceptance of novel foods.

The regulatory processes employed in the UK and the European Union to assess the safety of novel foods and novel food ingredients, including those resulting from the application of recombinant DNA technology (genetically modified foods), are described. Examples are given of yeasts that have been genetically modified and can be used in food and drink manufacture and food enzymes derived from genetically modified microorganisms that have been deemed safe for use by the UK regulatory system. Social acceptance of such novel foods or food ingredients is not uniform in countries of the developed world. Consumer concerns can be based on ethical considerations (scientists "playing God") or safety worries ("more testing needs to be done"). The general acceptance of such foods and food ingredients in Europe is still unclear.

Consumer Behavior↗
PubMed2005

Food and values: an examination of values underlying attitudes toward genetically modified- and organically grown food products.

This study addresses which specific values play a role in predicting participants' attitudes toward genetically modified food (GMF) and organically grown food (OGF). The first central question is whether the attitudes towards GMF and OGF are influenced by specific values and beliefs. The second central question is whether the attitudes towards GMF and OGF are related to each other, and whether the specific values underlying these two attitudes are also related to each other. A total of 100 participants responded to the Schwartz Value Survey and two questionnaires about GMF and organically grown food. When respondents scored high on the value power (dominance, submission), they rated GMF positively and OGF more negatively. Respondents who rated the value universalism (welfare for all people and protection of nature) high, rated OGF as positive. Furthermore, the relationship between attitudes and values was mediated by beliefs. These findings imply a meaningful relationship between specific values, beliefs, and these food-related attitudes, and suggest that values might play a role in explaining attitudes toward GMF and OGF products.

Adolescent↗
PubMed2004

[Genetically modified organisms in food--production, detection and risks].

The first genetically modified plant (GMP) was a tobacco resistant to antibiotics in 1983. In 1996, the first genetically altered crop, a delayed-ripening tomato was commercially released. In the year 2003, the estimated global area of GM crops for was 67.7 million hectares. To produce such a plant a gene of interest has to be isolated from the donor. Together with a promoter, terminator sequence and marker gene it has to be introduced into the plant cell which is then stimulated to generate a whole GMP expressing new characteristics (herbicide/insect resistance, delayed ripening). The last few months have seen a strong public debate over genetically modified organisms which has raised scientific, economic, political, and ethical issues. Some questions concerning the safety of GMPs are still to be answered, and decisions about their future should be based on scientifically validated information.

Animals↗
PubMed2004

Detection and traceability of genetically modified organisms in the food production chain.

Both labelling and traceability of genetically modified organisms are current issues that are considered in trade and regulation. Currently, labelling of genetically modified foods containing detectable transgenic material is required by EU legislation. A proposed package of legislation would extend this labelling to foods without any traces of transgenics. These new legislations would also impose labelling and a traceability system based on documentation throughout the food and feed manufacture system. The regulatory issues of risk analysis and labelling are currently harmonised by Codex Alimentarius. The implementation and maintenance of the regulations necessitates sampling protocols and analytical methodologies that allow for accurate determination of the content of genetically modified organisms within a food and feed sample. Current methodologies for the analysis of genetically modified organisms are focused on either one of two targets, the transgenic DNA inserted- or the novel protein(s) expressed- in a genetically modified product. For most DNA-based detection methods, the polymerase chain reaction is employed. Items that need consideration in the use of DNA-based detection methods include the specificity, sensitivity, matrix effects, internal reference DNA, availability of external reference materials, hemizygosity versus homozygosity, extrachromosomal DNA, and international harmonisation. For most protein-based methods, enzyme-linked immunosorbent assays with antibodies binding the novel protein are employed. Consideration should be given to the selection of the antigen bound by the antibody, accuracy, validation, and matrix effects. Currently, validation of detection methods for analysis of genetically modified organisms is taking place. In addition, new methodologies are developed, including the use of microarrays, mass spectrometry, and surface plasmon resonance. Challenges for GMO detection include the detection of transgenic material in materials with varying chromosome numbers. The existing and proposed regulatory EU requirements for traceability of genetically modified products fit within a broader tendency towards traceability of foods in general and, commercially, towards products that can be distinguished from each other. Traceability systems document the history of a product and may serve the purpose of both marketing and health protection. In this framework, segregation and identity preservation systems allow for the separation of genetically modified and non-modified products from "farm to fork". Implementation of these systems comes with specific technical requirements for each particular step of the food processing chain. In addition, the feasibility of traceability systems depends on a number of factors, including unique identifiers for each genetically modified product, detection methods, permissible levels of contamination, and financial costs. In conclusion, progress has been achieved in the field of sampling, detection, and traceability of genetically modified products, while some issues remain to be solved. For success, much will depend on the threshold level for adventitious contamination set by legislation.

Animals↗
PubMed2006

Attitudes towards genetically modified and organic foods.

Finnish students (N=3261) filled out a questionnaire on attitudes towards genetically modified and organic food, plus the rational-experiential inventory, the magical thinking about food and health scale, Schwartz's value survey and the behavioural inhibition scale. In addition, they reported their eating of meat. Structural equation modelling of these measures had greater explanatory power for attitudes towards genetically modified (GM) foods than for attitudes towards organic foods (OF). GM attitudes were best predicted by natural science education and magical food and health beliefs, which mediated the influence of thinking styles. Positive attitudes towards organic food, on the other hand, were more directly related to such individual differences as thinking styles and set of values. The results of the study indicate that OF attitudes are rooted in more fundamental personal attributes than GM attitudes, which are embedded in a more complex but also in a more modifiable network of characteristics.

Adolescent↗
PubMed1998

The EC novel foods Regulation--a UK perspective.

On 15 May 1997 the EC novel foods Regulation came into effect introducing a statutory pre-market approval system for novel foods across the whole of the European Union. A novel food is defined as a food which has not been consumed to a significant degree and includes foods containing or obtained from genetically modified organisms. The Regulation envisages an initial safety assessment at Member State level, although centralized procedures are available to resolve any objections between Member States. The most controversial aspect of the Regulation relates to the provisions for labelling genetically modified foods. Within the framework of the Regulation there is scope for labelling to be considered on a case by case basis, although the UK is pressing for all foods which may contain genetically modified material to be clearly labelled. To ensure that all Member States follow a consistent approach to the safety assessment of novel foods, the Commission has published a series of guidelines to accompany the regulation. The UK already has a well-developed system for assessing the safety of novel foods dating back to the approval of the first novel food in the UK in 1983.

Consumer Product Safety↗
PubMed2005

Food and the relation between values and attitude characteristics.

This survey showed that the values power (dominance over nature and resources) and universalism (respect for people and for nature) are related to attitudes toward genetically modified food (GMF) and organically grown food (OGF). Furthermore, these values have an influence on the centrality, commitment and ambivalence of these attitudes. Values that are positively related to an attitude influence how central this attitude is to a person. However, values that are negatively related to an attitude have a larger effect on the commitment of this attitude. No such pattern of effects was found for the relationship between ambivalence and values. These data suggest that centrality, commitment, and ambivalence are structurally different constructs that have a distinct relationship with specific values.

Adolescent↗
PubMedDate not supplied

Validation of PCR methods for quantitation of genetically modified plants in food.

For enforcement of the recently introduced labeling threshold for genetically modified organisms (GMOs) in food ingredients, quantitative detection methods such as quantitative competitive (QC-PCR) and real-time PCR are applied by official food control laboratories. The experiences of 3 European food control laboratories in validating such methods were compared to describe realistic performance characteristics of quantitative PCR detection methods. The limit of quantitation (LOQ) of GMO-specific, real-time PCR was experimentally determined to reach 30-50 target molecules, which is close to theoretical prediction. Starting PCR with 200 ng genomic plant DNA, the LOQ depends primarily on the genome size of the target plant and ranges from 0.02% for rice to 0.7% for wheat. The precision of quantitative PCR detection methods, expressed as relative standard deviation (RSD), varied from 10 to 30%. Using Bt176 corn containing test samples and applying Bt176 specific QC-PCR, mean values deviated from true values by -7to 18%, with an average of 2+/-10%. Ruggedness of real-time PCR detection methods was assessed in an interlaboratory study analyzing commercial, homogeneous food samples. Roundup Ready soybean DNA contents were determined in the range of 0.3 to 36%, relative to soybean DNA, with RSDs of about 25%. Taking the precision of quantitative PCR detection methods into account, suitable sample plans and sample sizes for GMO analysis are suggested. Because quantitative GMO detection methods measure GMO contents of samples in relation to reference material (calibrants), high priority must be given to international agreements and standardization on certified reference materials.

European Union↗
PubMed2006

Safety testing of GM-rice expressing PHA-E lectin using a new animal test design.

The 90-day animal study is the core study for the safety assessment of genetically modified foods in the SAFOTEST project. The model compound tested in the 90-day study was a rice variety expressing the kidney bean Phaseolus vulgaris lectin agglutinin E-form (PHA-E lectin). Female Wistar rats were given a nutritionally balanced purified diet with 60% parental rice, 60% PHA-E rice or 60% PHA-E rice spiked with 0.1% recombinant PHA-E lectin for 90 days. This corresponded to a mean daily PHA-E lectin intake of approximately 0, 30 and 100mg/kg body weight for each group, respectively. The spiking was used to increase the specificity and to demonstrate the sensitivity of the study. A range of biological, biochemical, microbiological and pathological parameters were examined and significant differences in weight of small intestine, stomach and pancreas and plasma biochemistry were seen between groups. Included in this paper are also data from the molecular characterisation and chemical analysis of the PHA-E rice, from the construction and production of the PHA-E lectin, and from the preceding 28-day in vivo study where the toxicity of the pure PHA-E lectin was determined. In conclusion, the combined use of information from the compositional analysis, the 28-day study and the characterisation of the PHA-E rice and the PHA-E lectin has improved the design of the 90-day study. The spiking procedure has facilitated the interpretation of the results of the study and transferred it into a valuable tool for the future safety testing of genetically modified foods.

Animals↗
PubMed2006

cDNA microarray screening in food safety.

The cDNA microarray technology and related bioinformatics tools presents a wide range of novel application opportunities. The technology may be productively applied to address food safety. In this mini-review article, we present an update highlighting the late breaking discoveries that demonstrate the vitality of cDNA microarray technology as a tool to analyze food safety with reference to microbial pathogens and genetically modified foods. In order to bring the microarray technology to mainstream food safety, it is important to develop robust user-friendly tools that may be applied in a field setting. In addition, there needs to be a standardized process for regulatory agencies to interpret and act upon microarray-based data. The cDNA microarray approach is an emergent technology in diagnostics. Its values lie in being able to provide complimentary molecular insight when employed in addition to traditional tests for food safety, as part of a more comprehensive battery of tests.

Food Microbiology↗
PubMed2000

Ethical issues in biotechnology.

New ethical questions have arisen from our ability to intervene in the structure of the genome. Responsible use of this technique requires ethical evaluation in which experts, potential beneficiaries and the general public should all participate. The examples of genetically modified food and of human genetics help to illustrate the issues involved.

Bioethics↗
PubMed2001

Risk communication--the perceptions and realities.

This paper defines risk communication and puts it into the perspective of risk analysis as a whole. Case studies originating for the food industry are described in the areas of food colours, pesticides and genetically, modified foods to exemplify both the difficulties of risk communication and the lessons that can be learned. This paper concludes by suggesting ways in which successful risk communication should be managed.

Communication↗
PubMed2000

The future relationship between the media, the food industry and the consumer.

The relationship between the media, the food industry and the consumer is probably at its lowest point as we start the new millennium. The frequency of food scares appears to be increasing and news reports sometimes seem both sensational and polarised. High profile issues like the development of bovine spongiform encephalopathy in the UK and the dioxin contamination of poultry products in Belgium have undermined consumer confidence in the food industry. The recent genetically modified foods' debate has served to demonstrate the gulf that has grown between the food industry, food safety experts and the public. This is a rift that has been exploited by environmental pressure groups and fuelled by the media. This paper examines some of the underlying causes of the current air of mistrust that seems to exist between the media, the food industry and the consumer. Also, by examining the projected trends in these root causes, it draws some conclusions for the future relationship between the parties involved and suggests some changes that may improve the present situation.

Consumer Product Safety↗