rDNA Technology & Food Uses Sana Javed UG 3- Section A

Recombinant DNA (rDNA) Technology Cutting a known DNA sequence from one organism & introducing it into another Recipient genotype ( & hence the phenotype) alteration

Food Safety DNA insertion- uncontrolled event Alterations in DNA may interfere with the regulation and expression of certain genes Toxins Allergens Nutritional change Such faulty insertions are unique to each insertional event, and thus it is practically impossible to search for every possible effect that a gene insertion might have. Mamalian host metabolism can be altered by taking in insect resistant plants that target GI tract enzymes Safeguards against this potential risk include avoiding transferring genes from the most commonly allergenic foods, including fish, shellfish, eggs, milk, soy, wheat, peanuts, and tree nuts. Use of genetic material from these sources would require extensive testing to prove the absence of allergenicity Change in nutritional content they could alter the cellular metabolism of the food-producing organism in unintended and unanticipated ways, and in turn, these alterations in metabolism could cause allergens or toxins to be produced in the food. Another possibility is that, as a result of these alterations in metabolism, the food-producing organism might fail to make some important vitamin or nutrient. Level of allergen or toxin production is also imp BT toxins

Environmental Concerns Escaping & spreading the engineered gene in the natural gene flow process Insect resistant crops- Non-specific threatening the wild type crop species for competition. disturb the ecosystem, posing a serious concern for the integrity of biodiversity.

Ethical and Social Issues Prohibited animal-derived genes in plant foods Ecosystem disruption

Safety Assessment Conducted under ground rules given by WHO, FAO & OECD Safety testing: Toxicological testing Allergenicity studies Nutritional analysis Environment: field allocation preventing horizontal gene transfer Ethical concerns: labeling foods contai-ning animal-derived genes ( Food and Agricultural Organization) (Organization for Economic Co-operation and Development) follows the basic concepts of risk assessment, risk management and risk communication. Any health hazards, if suspected under any circumstances in the finished product are labeled so that the consumer is aware of any potential risks of allergies and anaphylaxis, and of the nutritional charecteristics if they vary from the unengineered product. Labeling until longterm safety is established

Application of Recombinant DNA Technology in Agriculture Adeena Shafique

INTRODUCTION Application of recombinant DNA technology has primarily helped in producing three major types of transgenic plant having improved performances. These are: (1) Development of stress tolerant plants (2) Development of plants having improved yield (3) Transgenic plants as a source of biopharmaceuticals

Development of stress tolerant plant Plant resistant to environmental stress Herbicide Resistant plant Insect resistant plant Disease resistance plant

Plants resistant to Environmental stress Abiotic stresses: Drought, Heat, Cold, Too salty or acidic soils Genetically modified Tomato and Canola tolerate very high salt levels. Maize and papaya resistant to aluminum.

Herbicide Resistant Plants Herbicide-RoundupTM contains glyphosate. Glyphosate kills many plants. It binds to the plant enzyme EPSP synthase. rDNA technology modified EPSP gene. Soybean resistant to glyphosate. rDNA technology

Insect resistant plants Farmers can use insecticides but these are harmful for human health. Bt genes from Bacillus thuringiensis are used. Transgenic crops (e.g. cotton, rice, maize, potato, brinjal, cauliflower, cabbage etc.) with Bt genes have been developed and such transgenic varieties proved effective in controlling the insect pests.

Disease resistant plants Plants are susceptible to viral, bacterial, fungal diseases. Genes encoding viral coat protein expressed in plants. Protects the plant from subsequent infection. TMV coat protein gene expressed in tobacco plant protected it from TMV infection.

Development of plants having increased quality of plant products Golden Rice

Increase in quality of plant products Golden rice containing beta carotene to overcome vitamin A deficiency in regions where rice is the staple food Canola containing high levels of oleic acids Tomatoes which do not rot in room temperature Other vegetables and fruits with delayed ripening as well as modified flavor characteristics

Transgenic plant as a source of bio pharmaceuticals Edible vaccines- A reality in the future?! Expression of antigenic proteins in crops like banana and tomato. Great advantages- avoiding storage problems, easy delivery system, low cost.