Food Safety Assessment

Kevin Greenlees, PhD, DABT

Kathleen Jones, PhD

Describes the animal, construct, and proposed claim

Are there sequences that are likely to contain potential hazards to the animal, humans, or animals consuming food from that animal, or the environment? e.g., does the construct contain mobilizable sequences from viruses that may be endemic in that species?

Does the insertion of the rDNA construct pose a hazard to the animal, humans, other animals by feed, or the environment?

Are the genotype or phenotype changing over the product lifespan in a way that would affect the risks associated with the product? Is there a plan in place to monitor those changes?

What are the direct and indirect risks posed to the GE animal? (e.g., can surveying the health and other phenotypic characteristics of the animal inform us with respect to risk to the animal and potential human food safety concerns?)

What are the risks of direct or indirect adverse outcomes associated with the consumption of the GE animal as food or feed?

Food/Feed Safety

What hazards/risks have been identified in the hierarchical review?

If GE Animal Not for Food

Established Food Safety Standard

The food safety standard is reasonable certainty of no harm

– NOT absolute safety

Whole Foods

Toxicological testing of whole foods in animal models is challenging

Complex mixtures Wide variation in composition Impact on dietary balance High dose testing not possible

Outcome Characterization

Approach

Identify and characterize hazards Direct effects Indirect effects

Analytical methods

Direct v IndirectIntended v Unintended

Direct Adverse Effect (Food Safety) adverse outcome resulting from human consumption of edible products from the rDNA animal coming into contact with the construct or its gene product(s)

Indirect Adverse Effect (Food Safety) adverse outcome resulting from human consumption of edible products from the rDNA animal that contain hazards due to the construct or gene product perturbing the food animal’s physiology

Intended effects changes in the rDNA animal brought about deliberately by introduction of the rDNA construct and its predicted gene product(s). These may or may not pose direct or indirect effects on food safety.

Unintended effects changes in the rDNA animal resulting from the interaction of the rDNA construct or its gene product(s) with the physiology of the animal such that its metabolism is altered. These may or may not pose direct or indirect effects on food safety.

Direct Effects

Result from the expression product(s) of the inserted construct directly producing harm

Toxicological testing on case-by-case basisAllergic assessment of proteins new to food

Indirect Effects

Effects other than direct impact of the expression product in food.Nutritional deficiency identified in

compositional analysis

Conceptual Overview of Food Safety Evaluation

Construct Gene Product

Direct Effects

Indirect Effects

Indirect Effects

Direct Effects

None (DNA is GRAS)

Insertional Mutagenesis in structural or regulatory region

Consumption of edible product containing GP causes toxicity

(allergenicity, GI disturbance, other tox)

Metabolic Δ such that consumption of edible tissue may pose risk

(altered levels of expected nutrients, inherent metabolites or sequestered xenobiotics)

Conceptual Overview of Food Safety Evaluation

The previous slide is a graphical summary of how one may approach the evaluation of food safety of edible products from GE animals. It indicates a GE animal, the construct that goes into it, and the resulting gene expression products. It subsequently indicates direct and indirect effects that may occur as the result of the construct or the expression products. The construct is not expected to cause direct effects as the agency has previously determined that DNA is generally recognized as safe (GRAS). Indirect effects caused by the construct could result from insertional mutagenesis in either structural or regulatory regions of the genome.

The gene product can cause direct effects via the consumption of edible products, products containing gene products that cause toxicity (allergenicity, gastrointestinal disturbance, or other toxicity). Indirect toxicity can result from metabolic changes such that consumption of edible tissue that may pose risk, for example, altered levels of expected nutrients, inherent metabolites or sequestered xenobiotics).

For a tolerance For identity

Analytical Methods for GE Animal

Only in food producing animals Only if a tolerance is needed Demonstrates marker analyte present at or

below tolerance in target tissue

Analytical Method for a Tolerance

o Identifies approved GE animal in mixed populationo Determines edible tissue is from approved GE

animalo Discriminates approved product from “knock-off”o Practical in a regulatory laboratoryo May provide useful information if durability failure

Analytical Method for Identity: Characteristics

Food/Feed Safety of

Information Reviewed Sponsor affirmation Animal identification; facilities; containment procedures Animal and product disposition methods and records “Regulatory Method” procedures for transgene identification

for animals and edible tissues

Conclusions Plan likely to ensure that GE animals will not enter the food or

feed supply Regulatory method adequate to identify animals/meat

No food/feed from this lineage of GE animals will enter food/feed supply