Genetic Engineering Overview and Basics

Study Notes

Genetic engineering modifies or introduces genes into host organisms or cells.
This process involves outlined procedures in genetic engineering.
It compares classical breeding methods with modern genetic engineering techniques.
It describes DNA insertion procedures.
It explains how genetically modified organisms are determined.

DNA (gene) → RNA (transcript) → Protein (trait)
Errors in copying or inserting genes can alter the protein product, potentially leading to unforeseen outcomes

Humans domesticate plants and animals for desirable traits like food, medicine, or other purposes.
Examples of plants with desirable traits include domesticated corn.
Examples of animals with desirable traits include domesticated chickens.

For centuries, humans used classical breeding to improve traits in animals and plants.
It mainly involves mating organisms with desired traits.

Recombinant chromatids result from crossing over.
DNA recombination can be manipulated:
- by cutting DNA segments containing genes of interest.
- by transferring those segments to a host.

Biotechnology integrates biology and technology.
Genetic engineering manipulates genetic structures
Recombinant DNA technology uses molecular tools to modify desired traits, including:
- introducing new traits
- increasing gene expression to enhance traits
- disrupting inhibition to enhance traits

Purification, Isolation, and Splicing:
- Foreign DNA is purified.
- Restriction enzymes cut the DNA at specific points.
- Sticky ends facilitate ligation (joining).
Ligation:
- Sticky ends are joined together by DNA ligase.
- Vectors, such as plasmids, are used to transfer the DNA.
Transformation:
- Recombinant DNA is introduced into host cells (transformation).
- Methods include:
  - Biolistics ("gene gun")
  - Heat shock
  - Electroporation

PCR (Polymerase Chain Reaction) amplifies small amounts of DNA for sequencing or cloning. This is more efficient than traditional cloning methods.

Online databases, like gene banks, help identify potential source organisms for desired genes or traits.
Common examples include GenBank and Protein Data Bank.

Insulin production is an example of applying recombinant DNA technology to medicine.
Insulin gene cloned and introduced into bacteria, which produce human insulin for treating diabetes.

GMOs result from the introduction of new traits in an organism.
Examples include:
- Flavr Savr tomato (delayed ripening)
- Bt corn and Bt eggplant (toxin production for pest resistance)
- chymosin (Industrial fermentation for enzyme production).

Genetic engineering utilizes biotechnology to enhance traits and increase organism value.
Recombinant DNA technology follows DNA replication principles.
PCR amplifies DNA quickly.
Gene technology can have both positive and negative effects on the immediate community, humans, and biodiversity.