Introduction to Genetic Engineering in Agriculture

Introduction to Genetic Engineering in Agriculture

• Genetic engineering in agriculture is the process of introducing a gene with a specific characteristic into a cell's chromosome to improve crop variety, ensure food security, and enhance crop quality and yield.
• This technology is used to introduce beneficial traits into crops.

Key Questions

• How are genes isolated and amplified for cloning?
• How can specific DNAs or RNAs be identified in mixtures?
• How is DNA amplified without cloning?
• How is amplified DNA used in genetics?
• How are DNA technologies applied to agriculture?

Lecture Outline

• Introduction
• Foundations of Genetic Engineering
• Techniques in Genetic Engineering
• Applications of Genetic Engineering in Agriculture
• Examples of Genetic Engineering in Agriculture
• Ethical, Legal, and Social Considerations

Genetic Engineering in Agriculture

• It is the process of introducing a gene with a particular character inside the chromosome of a cell
• Usually, it helps to improve crop variety
• Ensures food security
• Introduce beneficial traits
• Raise the quality and yield of crops

Introduction

• Scientists have developed bacteria for medication, crops with built-in pesticides, and bioluminescent dogs.
• Humans have been altering the genetics of organisms for over 30,000 years through selective breeding.

Genetic Engineering

• Genetic engineering (also called genetic modification or genetic manipulation) is the modification and/or manipulation of an organism's genes through technology.
• This manipulation adjusts the genetic makeup of cells, including transferring genes between different species to create improved organisms.
• New DNA is acquired by isolating/copying or artificially synthesizing the target genetic material (using recombinant DNA methods).
• The new DNA is integrated into the host organism by constructs. This technique can also remove genes ("knock out" genes).
• Insertion of new DNA can be random or targeted in a specific region/part of the genome.

History

• The first GMO (genetically modified organism) was a bacterium created by Herbert Boyer and Stanley Cohen in 1973.
• The first genetically engineered animal was a mouse that inserted foreign DNA, created by Rudolf Jaenisch in 1974.
• Genentech (a company focusing on genetic engineering) was founded in 1976 and initiated the production of human proteins.
• Human insulin was produced in 1978, and insulin-producing bacteria were commercially produced in 1982
• Genetically modified food was available to consumers from 1994, with the Flavr Savr tomato as an early example of a GM crop.
• More recent GM crops are modified for pest resistance to insects and herbicides.

Ancient Genetic Modification

• Dogs are thought to be the first organisms artificially selected by humans.
• Wild wolves in East Asia were adopted as scavengers about 32,000 years ago and subsequently domesticated.
• Artificial selection also pertains to the development of plants and dates back to 7800 BCE.
• Archaeological discoveries in Southwest Asia demonstrate domesticated wheat varieties.

The Birth of Modern Genetic Modification

• Examples of genetic engineering in agriculture include the development of crops resistant to specific types of pests, herbicides, disease, and conditions.
• Golden rice is an example of a crop with enhanced nutritional traits like vitamin A.

Other Examples of GMOs

• Different crops (apples, potatoes, canola, alfalfa, field corn, soybeans, cotton, sugar beets, sweet corn, summer squash) are engineered for specific purposes and traits.

The GMO Process

• Step 1: Trait identification
• Scientists determine the genes to develop resistance to disease, pests, or drought.
• Step 2: Transformation
• Transferring the identified gene into plant seeds to create GM organisms.
• Step 3: Regulatory Science
• Extensive testing of the GM product for safety & health across numerous studies.
• Step 4: Greenhouse Testing
• Experiments to validate the efficacy of the GM product created.
• Step 5: Field Testing
• Implementation of the GM product into real-world agricultural situations.
• Step 6: Getting seeds to farmers
• Selection of the best seeds that benefit the farmer’s farms.
• Step 7: Getting GMOs to Market
• Detailed review of testing & safety procedures, ensuring that the new GMO variety will be used safely.

Techniques in Genetic Engineering

• Gene Cloning and Recombinant DNA technology
• Genome editing using CRISPR-Cas9
• RNA interference and gene silencing
• Plant tissue culture and micropropagation.

DNA Technology

• DNA technology is built upon two basic foundations in molecular biology.
• DNA's ability to recognize and bind to specific proteins is important. These proteins recognize and bind to specific base sequences on the DNA helix.
• The complementary binding property of DNA and RNA sequences (single stranded) is also key. When these sequences are complementary, they bind together to form double-stranded molecules.

Generating Recombinant DNA Molecules

• Genomic DNA is obtained directly from an organism's chromosomes to produce the GMO.
• Complementary DNA (cDNA) are more useful than genomic sequences because introns are removed. mRNA is a better predictor of polypeptide sequence since introns are removed
• Chemically synthesized DNA might be essential if the target base sequence is inaccessible or unavailable from genomic or cDNA sources.

Cutting Genomic DNA

• Restriction fragments are created by restriction enzymes that precisely cut DNA by recognizing specific sequences. These fragments can then be joined together.

Restriction Enzymes

• Cleave DNA into fragments for easier manipulation. Restriction enzymes create staggered cuts. These cuts generate sticky ends which can result in recombinant DNA.

2-Attaching Donor and Vector DNA

• Donor DNA is combined with a vector to produce a recombinant plasmid. This involves using restriction enzymes to cut both the donor DNA and the vector DNA.
• The fragments are joined using DNA ligase to create a new molecule.

3-Amplification Inside a Bacterial Cell

• The recombinant vector containing a segment of donor DNA is transferred into a host bacterial cell.
• The bacteria, with its natural replication mechanism, amplifies the recombinant plasmid.

Vectors for DNA Cloning

• Vectors, such as pBR322 and pUC18 are essential in genetic engineering.
• They carry the target DNA fragment and enable its replication within the host cell.
• The ability to recognize if a DNA segment was transferred successfully is an important aspect in this process.

Take Away Message for Gene Cloning

• In gene cloning, single recombinant vectors are introduced into recipient bacterial cells. Replication of the vector amplifies the new DNA.

What is the process of GM?

• GMOs are created through a specific type of plant breeding that alters or manipulates a plant's DNA to introduce traits that cannot be achieved through traditional methods.
• Genetic changes can involve moving, turning off, or inserting genes from one organism to another.

GMO Process (Steps)

• Trait Identification--research used to identify genes responsible for beneficial traits in terms of disease, pest, or drought resistance.
• Transformation - introducing/transferring the identified gene into plant seeds
• Regulatory Science—thorough testing to prove safety of the GM product to humans, environment, and animals.
• Greenhouse Testing—conducting further tests and experiments in controlled environments.
• Field Testing—field trials provide critical evaluation data for the new product.
• Seeds to Farmers—farmers will choose seeds that work best for their crops.

GMOs Around the World

• In 2016, 18 million farmers grew GMO crops, mostly in developing countries.
• 26 countries cultivated GMOs.
• 7 of the countries were industrialized.

Beyond Traditional Transgenic Technology

• Genetic engineering extends beyond traditional methods. New possibilities are constantly emerging and expanding.

Ethical Considerations in Genetic Modification

• Research and development, use, and testing of GM technologies are subject to ethical, legal, and social factors.
• These factors will inform decisions and regulations pertaining to the use of these technologies.

Ecological Effects of GMOs

• Transgenic organisms might spread and establish populations. This could disrupt biotic communities and ecosystems/
• The GMO's capacity to survive, reproduce, and spread poses other challenges.
• Effects on living organisms need to be considered/
• The release of GMOs into different ecosystems will result in potential unforeseen effects on different organisms.
• There are possible effects on ecological communities.
• Knowledge of how ecological communities will be impacted is critical to making decisions about regulations.

Environmental Impact Assessment

• This tool assesses the effects of plans, policies, or programs on the environment.
• It considers the environmental impacts and threats before proceeding with the project or action with this tool.
• It includes environmental considerations for decision-making processes.

Health Aspects of Final GMO

• The method for monitoring safety must be included in the methods used for assessing safety.
• The final GMO's safety must be tested via multiple independent assessors
• Assessments should include aspects of toxicity, allergenicity, pathogenicity, and known/anticipated habitats.

More Environmental Considerations

• GMOs may escape the laboratory or the facility, impacting their environment.
• GMO interaction must be considered/analysed/assessed with other organisms/species to predict impacts.
• The effects on toxicity, allergenicity etc need to be researched.
• The use of the GMO in ecosystems must also be studied.
• The impacts on biogeochemical processes need to be evaluated.

GMOs Safety

• GMOs are scrutinized by numerous food safety organizations. GMOs are assessed and tested rigorously to guarantee their safety and efficacy.
• GMO safety is a major concern in societies.

GMO Research, Review and Regulation

• GMOs typically take between 5-7 years and $130 million of R&D to come to market.
• There are many regulatory bodies, typically 75 or more, that review research and products.
• Regulation bodies include different states/countries that conduct numerous studies assessing health and environmental safety.

Economic Benefits of GMO Crops

• Global gains of almost $225 billion generated by biotech crops.
• Improved yields contribute heavily.
• Reduced production costs are a major factor.

Environmental Benefits of GMO Crops

• Reduced pesticide use.
• Reduction in carbon emissions.

Explore the fascinating field of genetic engineering and its applications in agriculture. This quiz covers fundamental techniques, ethical considerations, and the significant impact of genetic modifications on crop variety and yield. Test your knowledge on how genetic technologies are shaping the future of food security.