Genetic Engineering and GMOs Overview

Genetic Engineering

• Genetic engineering is the direct modification of an organism's genome, which includes the list of specific traits (genes) stored in the DNA.
• Modifying the genome allows engineers to give organisms desirable properties.
• Genetically modified organisms (GMOs) are created through genetic engineering.

GMO Development History

• 1973: First genetically modified bacteria were created.
• 1974: Genetically modified mice were created.
• 1982: First commercial development of GMOs (insulin-producing bacteria).
• 1994: Genetically modified foods began to be sold commercially.
• 2003: GMOs were widely sold as food.

GMO Process

• Genetic changes affect protein synthesis of the organism.
• Modifying which proteins are produced alters overall organismal traits.
• Genetic modification can be done through:
  • Direct gene replacement (recombination)
  • Gene removal
  • Inserting new genetic material randomly or in targeted locations
  • Altering existing genes

GMO Bacteria

• Bacteria are common GMOs due to their simple DNA structures, allowing for easy manipulation.
• One use of genetically modified bacteria is creating hydrocarbons like plastics or fuels, usually made from fossil fuels.
  • Cyanobacteria can produce plastic (polyethylene) and fuel (butanol).
  • E. coli bacteria can produce diesel fuel.

Engineering Plants

• Genetic engineering can modify plants to address everyday problems like hunger, weather issues, and insecticide/pollution.

GMO Papaya

• Dr. Garritt Wilder introduced the Solo papaya in Hawaii in 1910, and it became the dominant type in commercial papaya production.
• Hawaii's papaya industry was greatly impacted by the papaya ringspot virus in Oahu starting in the 1950s.

Genetically Modified Crops (2010)

• 93% of soybeans, 93% of cotton, 86% of corn, and 95% of sugar beets were genetically modified in the US.
• Bt-corn is a common example, where a gene from Bt bacteria is added to produce a protein toxic to insects.

Other Reasons to Modify Crops

• Improve insect resistance
• Enhance herbicide resistance
• Improve drought/freeze resistance
• Increase disease resistance
• Improve crop yields
• Speed up plant growth
• Enhance nutritional value
• Extend shelf life

Engineering Animals

• Discusses the potential use of genetic engineering to solve animal-related problems.

Bioluminescent Animals

• Uses: Protein tracking; disease detection using bioluminescent imaging (BLI) to identify different cell types; novelty pets (GloFish are available).

Fast-Growing Salmon

• Genes from other fish types cause these salmon to constantly produce growth hormones. This results in faster growing salmon.

Less Smelly Cows

• Modifying bacteria responsible for methane production in cattle results in a 25% reduction in cattle flatulence.

Web-Producing Goats

• Spider genes in goats enable production of spider webs/silk.

GMO Concerns

• Risks to human health and safety from unsafe genetically modified foods and animals.
• Environmental harm
• Increased pesticide/herbicide use
• Farmers' health concerns
• Seed & pollen drift
• Creation of herbicide-resistant "super weeds"
• Potential safety concerns with genetic engineering in humans
• Several countries have restrictions on GMO production and sale.

Vocabulary/Definitions

• DNA: Deoxyribonucleic acid
• Gene: Molecular unit containing trait-related information
• Genome: Entire set of genes in an organism
• GMO: Genetically modified organism
• Nucleotide: Building block of DNA
• Plasmid: Circular DNA used by bacteria
• Protein: Large biomolecule
• Recombinant DNA: DNA with a section replaced
• Restriction enzyme: Enzyme that cuts DNA in specific sequences
• Trait: Distinguishing characteristic

What is DNA?

• DNA is a large biomolecule that contains an organism's complete genetic instructions.
• Every living cell contains DNA, as do many viruses.
• The basic building block of DNA is the nucleotide.
• A DNA molecule can contain billions of nucleotides.

What is DNA?

• DNA contains instructions for creating proteins.
• A single gene is a small segment of DNA containing instructions for a single protein.
• Thousands of genes can make up an entire set or genome, unique to the organism.

Why are Proteins Important?

• Proteins perform the work in organisms.
• Examples: Catalysts for reactions, cell signaling, transporting molecules across membranes, and creating structures.
• The instruction to make a protein is carried by the gene which when expressed is used.