Novel Food Information - Arctic Apple Events GD743 and GS784

Health Canada has notified Okanagan Specialty Fruits Inc. that it has no objection to the food use of Arctic Apple events GD743 (Golden Delicious (GD) variety) and GS784 (Granny Smith (GS) variety). The Department conducted a comprehensive assessment of these varieties according to its Guidelines for the Safety Assessment of Novel Foods. These Guidelines are based upon internationally accepted principles for establishing the safety of foods with novel traits.

Background

The following provides a summary of the notification from Okanagan Specialty Fruits Inc. and the evaluation by Heath Canada and contains no confidential business information.

1. Introduction

Okanagan Specialty Fruits Inc. developed Arctic Apple events GD743 and GS784 to be non-browning when exposed to mechanical damage such as slicing or bruising. Recombinant DNA techniques were used in order to make the apples non-browning.

The safety assessment performed by Food Directorate evaluators was conducted according to Health Canada’s Guidelines for the Safety Assessment of Novel Foods. These Guidelines are based on harmonization efforts with other regulatory authorities and reflect international guidance documents in this area (e.g., Codex Alimentarius). The assessment considered: how Arctic Apple events GD743 and GS784 were developed; how the composition and nutritional quality of Arctic Apple events GD743 and GS784 compare to non-modified varieties; and the potential for Arctic Apple events GD743 and GS784 to be toxic or cause allergic reactions. Okanagan Specialty Fruits Inc. provided data that demonstrates that Arctic Apple events GD743 and GS784 are as safe and of the same nutritional quality as traditional apple varieties used as food in Canada.

The Food Directorate has a legislated responsibility for pre-market assessment of novel foods and novel food ingredients as detailed in the Food and Drug Regulations (Division 28). Food use of Arctic Apple events GD743 and GS784 are considered novel foods under the following part of the definition of novel foods: "c) a food that is derived from a plant, animal or microorganism that has been genetically modified such that

1. the plant, animal or microorganism exhibits characteristics that were not previously observed in that plant, animal or microorganism."

2. Development of the Modified Plant

The petitioner has provided information describing the methods used to develop Arctic Apple events GD743 and GS784 and the molecular biology data that characterize the genetic change which makes the apple events non-browning through the expression of a polyphenol oxidase (PPO) enzyme suppression cassette which down-regulates enzyme levels through RNA interference (RNAi). In addition, these apple lines also express a selectable marker sequence, nptII, which codes for the neomycin phosphotransferase protein (NptII) which confers resistance to kanamycin in plants.

Arctic Apple events GD743 and GS784 were genetically modified using Agrobacterium-mediated transformation of apple leaf tissue with the vector GEN-03. The transfer DNA (T-DNA) from the transforming plasmid contains the PPO suppression cassette and the coding sequence for the NptII protein. The PPO suppression cassette consists of four apple genes. The nptII gene sequence is from the E. coli Transposon Tn5.

3. Characterization of the Modified Plant

Southern blot analysis and DNA sequencing of Arctic Apple events GD743 and GS784 demonstrated the presence of multiple copies of the T-DNA. Further analysis showed that the multiple copies did not result in new potential open reading frames and that the expression of a new hypothetical protein would not occur. The T-DNA inserted at multiple sites of the apple genome, with further analysis showing that no endogenous genes were interrupted by the presence of the insert. It was confirmed that one copy of plasmid backbone DNA was present in GS784, and no plasmid backbone DNA was present in GD743.

The stability of the inserted T-DNA was evaluated. These results, along with segregation data, demonstrated the stability of Arctic Apple events GD743 and GS784 at the genomic level as well as the segregation of the trait according to Mendelian inheritance principles based on the number of copies.

4. Product Information

Arctic Apple events GD743 and GS784 differ from conventional apples by the insertion of the PPO suppression cassette and its associated regulatory elements, as well as the nptII gene and its associated regulatory elements. The apples have delayed browning as compared to conventional apples.

5. Dietary Exposure

The genetic modification of Arctic Apple events GD743 and GS784 is not intended to alter any of its nutritional aspects when compared to undamaged, non-genetically modified apples. Following damage (e.g., slicing, bruising), the genetically modified apples contain higher levels of vitamin C compared to non-genetically modified counterparts. This is because vitamin C is a substrate in the browning process, and when PPO enzyme levels are reduced subsequent vitamin C oxidation is also reduced. Arctic Apple events GD743 and GS784 are not intended to be nutritionally enhanced and do not differ significantly from conventional counterparts.

6. Nutrition

The nutrient data was obtained from mature fruit harvested in 2005 and 2009. For each event (GD743 and GS784) and control (GD and GS), fruit was harvested from 2 sites. To sample the fruit, boxes of harvested fruit representing each event were randomly chosen. Three boxes of fruit were chosen for each Arctic Apple event (GD743 and GS784) and control (GD and GS) and from these, fruits were randomly chosen for each event and control for composite samples.

The nutritional and compositional analytes measured in the apple samples included: proximate (moisture, protein, fat, ash, carbohydrate), sugar, dietary fibre, potassium, vitamin C and phenolics. These nutrients were assessed in apples from events GD743 and GS784 and compared to the control GD and GS to determine if they were nutritionally equivalent. The data was also compared to United States Department of Agriculture (USDA) and Canadian Nutrient File (CNF) data as well as literature values.

The nutrient composition of Arctic Apple events GD743 and GS784 have been shown to be similar to conventional apple. Of all the analytes measured, only the vitamin C and phenolic levels in the GD743 and GS784 apples were significantly different (higher) as compared to controls. These differences were acceptable since they are expected based on the trait and are also within literature values for vitamin C and phenolic compounds.

7. Chemistry/Toxicology

The toxicological impacts of the novel molecular products produced by Arctic Apples GD743 and GS784 were examined. These products were considered to be the small interfering RNA molecules (siRNAs) expressed by the suppression sequence, as well as the protein selection marker, NptII.

The potential for exogenous siRNA to silence human protein expression was considered. Data investigating this potential was provided. The absorption of exogenous siRNA systemically into the human body was examined and found to be unlikely based on numerous biological barriers.

In the event that the novel siRNA molecules were absorbed systemically or locally from the GI tract, they would not be anticipated to affect the expression of any human proteins. Bioinformatic analyses demonstrated that the predicted siRNA molecules produced by Arctic Apples did not have significant homology to human protein-coding genomic regions or to human transcript sequences. Therefore, these siRNA molecules were not expected to interfere with human protein expression.

The protein selection marker gene, nptII, was previously approved for several genetically modified crops and a history of safe use has been demonstrated for the NptII protein. Furthermore, the NptII protein is expressed at negligible levels and does not accumulate in mature Arctic Apple fruit. Expression of NptII in Arctic Apple does not represent a toxicological concern.

Apples are not considered a priority allergen in Canada. While allergenic responses to apples do occur, severe reactions are rare and are restricted to exposure with the fresh fruit. The impact of the genetic modifications in Arctic Apples on the allergenicity of these apples as compared to conventional varieties was examined. The suppression sequence coding for novel siRNAs does not express any novel protein products and therefore will not impact the allergenicity of Arctic Apples.

In conventional apples, oxidised phenols, which are the metabolic product of polyphenol oxidase, bind endogenous allergenic proteins. Due to the decreased level of polyphenol oxidase in Arctic Apples, changes in the availability of endogenous allergenic proteins in these apples are a possibility. However, it should also be noted the levels of endogenous allergens in conventional apples are naturally highly variable and are influenced by various environmental factors. Furthermore, field trials demonstrated that the total protein and phenol content of Arctic Apples were within literature ranges. Considering the above, the potential changes in the availability of endogenous allergens in Arctic Apples, as compared to conventional apples, is not considered to pose an additional health risk to individuals sensitive to apples.

The expressed protein, selection marker, NptII, does not pose a concern for increased allergenicity of Arctic Apples as compared to conventional apples. The history of safe use established for this protein and the negligible levels of NptIIexpressed in Arctic Apples, serve to support this claim.

Based on the above, Arctic Apple events GD743 and GS784 are not considered to pose a greater toxicological or allergenic risk than conventional apple varieties.

Conclusion

Health Canada's review of the information presented in support of the food use of Arctic Apple events GD743 and GS784 does not raise concerns related to food safety. Health Canada is of the opinion that food derived from Arctic Apple events GD743 and GS784 is as safe and nutritious as food from current commercial apple varieties.

Health Canada's opinion deals only with the food use of Arctic Apple events GD743 and GS784. Issues related to its use as animal feed have been addressed separately through existing regulatory processes within the Canadian Food Inspection Agency (CFIA). From their assessment, the CFIA concluded that there are no concerns from an environmental and feed safety perspective. This perspective is applicable to the food and feed products derived from Arctic Apple events GD743 and GS784 destined for commercial sale.

This Novel Food Information document has been prepared to summarize the opinion regarding the subject product provided by the Food Directorate, Health Products and Food Branch, Health Canada. This opinion is based upon the comprehensive review of information submitted by the petitioner according to the Guidelines for the Safety Assessment of Novel Foods.

(Également disponible en français)

For further information, please contact:

Novel Foods Section
Food Directorate
Health Products and Food Branch
Health Canada, PL2204E
251 Frederick Banting Driveway
Ottawa (Ontario) K1A 0K9
novelfoods-alimentsnouveaux@hc-sc.gc.ca