Health status and potential uptake of transgenic DNA by Japanese quail fed diets containing genetically modified plant ingredients over 10 generations

Horizontal gene transfer from genetically modified plants - Regulatory considerations

Gene technology regulators receive applications seeking permission for the environmental release of genetically modified (GM) plants, many of which possess beneficial traits such as improved production, enhanced nutrition and resistance to drought, pests and diseases. The regulators must assess the risks to human and animal health and to the environment from releasing these GM plants. One such consideration, of many, is the likelihood and potential consequence of the introduced or modified DNA being transferred to other organisms, including people. While such gene transfer is most likely to occur to sexually compatible relatives (vertical gene transfer), horizontal gene transfer (HGT), which is the acquisition of genetic material that has not been inherited from a parent, is also a possibility considered during these assessments. Advances in HGT detection, aided by next generation sequencing, have demonstrated that HGT occurrence may have been previously underestimated. In this review, we provide updated evidence on the likelihood, factors and the barriers for the introduced or modified DNA in GM plants to be horizontally transferred into a variety of recipients. We present the legislation and frameworks the Australian Gene Technology Regulator adheres to with respect to the consideration of risks posed by HGT. Such a perspective may generally be applicable to regulators in other jurisdictions as well as to commercial and research organisations who develop GM plants.

Weight of the evidence: independent research projects confirm industry conclusions on the safety of insect-protected maize MON 810

The cumulative weight of the evidence demonstrates the safety and equivalence of genetically engineered (GE) crops compared to the conventional varieties from which they have been derived. Confirmatory toxicology and animal nutrition studies have nevertheless become an expected/mandated component of GE crop safety assessments, despite the lack of additional value these studies provide for product safety assessment. Characterization and safety data (e.g. trait protein safety; molecular, compositional, and agronomic/phenotypic assessments), and animal feeding studies form a weight of the evidence supporting the safety of insect-protected maize MON 810. Independent animal testing has recently confirmed the lack of MON 810 toxicity in subchronic and chronic toxicity studies. These results could have been predicted from the available safety data. Animal testing of GE crops should be supported by testable scientific hypotheses and testing should be consistent with ethical obligations to reduce, refine, and replace (3Rs) animal testing when possible.

Health effects of feeding genetically modified (GM) crops to livestock animals: A review

A large share of genetically modified (GM) crops grown worldwide is processed into livestock feed. Feed safety of GM crops is primarily based on compositional equivalence with near-isogenic cultivars and experimental trials in rodents. However, feeding studies in target animals add to the evaluation of GM crops with respect to animal health. This review aimed to evaluate the possible health effects of feeding GM crops to livestock by reviewing scientific publications on experimental studies in ruminants, pigs, and poultry in which at least one of the following health parameters was investigated: body condition score, organ weight, haematology, serum biochemistry, histopathology, clinical examination, immune response, or gastrointestinal microbiota. In most experiments, either Bt (Bacillus thuringiensis) maize, Roundup Ready (RR) soybean, or both were fed to livestock animals. Significant differences (P<0.05) in health parameters were most often observed when animals were fed Bt maize, although most effects measured were unlikely to be of biological significance and were within normal biological ranges. Health effects of RR soybean were only observed in one experimental study with broilers. Based on this literature review, we conclude that there is no clear evidence that feed composed of first generation GM crops has adverse effects on animal health.

Detection of dietary DNA, protein, and glyphosate in meat, milk, and eggs

Products such as meat, milk, and eggs from animals that have consumed genetically engineered (GE) feed are not currently subject to mandatory GE labeling requirements. Some voluntary "non-genetically modified organism" labeling has been associated with such products, indicating that the animals were not fed GE crops, as there are no commercialized GE food animals. This review summarizes the available scientific literature on the detection of dietary DNA and protein in animal products and briefly discusses the implications of mandatory GE labeling for products from animals that have consumed GE feed. Because glyphosate is used on some GE crops, the available studies on glyphosate residues in animal products are also reviewed. In GE crops, recombinant DNA (rDNA) makes up a small percentage of the plant's total DNA. The final amount of DNA in food/feed depends on many factors including the variable number and density of cells in the edible parts, the DNA-containing matrix, environmental conditions, and the specific transgenic event. Processing treatments and animals' digestive systems degrade DNA into small fragments. Available reports conclude that endogenous DNA and rDNA are processed in exactly the same way in the gastrointestinal tract and that they account for a very small proportion of food intake by weight. Small pieces of high copy number endogenous plant genes have occasionally been detected in meat and milk. Similarly sized pieces of rDNA have also been identified in meat, primarily fish, although detection is inconsistent. Dietary rDNA fragments have not been detected in chicken or quail eggs or in fresh milk from cows or goats. Collectively, studies have failed to identify full-length endogenous or rDNA transcripts or recombinant proteins in meat, milk, or eggs. Similarly, because mammals do not bioaccumulate glyphosate and it is rapidly excreted, negligible levels of glyphosate in cattle, pig and poultry meat, milk, and eggs have been reported. Despite consumer concern about the presence of trace concentrations of glyphosate that might have been applied to feed crops and/or the presence of rDNA or recombinant proteins in meat, milk, and eggs, the available data do not provide evidence to suggest that products from animals that have consumed approved GE feed crops differ in any distinguishable way from those derived from animals fed conventional feed or that products from animals fed GE feedstuffs pose novel health risks.