GEN BIO 2 | Genetic Engineering

Selective Breeding

also known as artificial selection, it is a process used by humans to develop new organisms with desirable characteristics

Improved Plants from Genetic Engineering

• Increased crop quality and yield

• Increased tolerance of environmental pressures

• Resistance to viruses, fungi, and bacteria

• Increased tolerance to insect pests

• Increased tolerance of herbicides

Classical Breeding

uses interbreeding of closely or distantly related individuals to produce new varieties or lines with desirable properties

Genetic Engineering

involves the use of molecular techniques to modify the traits of a target organism to introduce new traits, increased expression of desired gene, and inhibit the expression of undesirable gene

Biotechnology

the manipulation of organisms or their components to make useful products

Recombinant DNA Technology

a molecule contsining DNA from two different sources or species

Transgenic Organism

an individual with recombinant DNA

How to make Recombinant DNA

• Researcher requires a vector and cuts the plasmid using restriction enzymes that cut the DNA at specific sequences.

• Seal the foreign piece of DNA in the plasmid using DNA ligase.

• Return the plasmid to the bacterial cell.

• Bacterial cell reproduces thus replicating the desirable gene or gene cloning.

• Researchers isolate copies of the clone gene from the bacteria.

Restriction Enzymes and DNA Ligase

They ensure only the desired gene is inserted in creating a transgenic organism.

Ways to Insert Plasmids into Organism Tissues

• Gene Gun

• Heat Shock Treatment

• Electroporation

Gene Gun

it is sued to fire small metal (gold or tungsten) particles coated with DNA into plant tissues

Heat Shock Treatment

The bacteria is heated to 42 ºC for 1 minute causing the pore sizes of its cell membrane to open, making it more permeable for plasmid DNA. Then, the bacterial cell will be cooled down to 4 ºC.

Electroporation

The expansion of the membrane pores is done through a high intensity electric “shock,” usually for gene insertion of genes into mammalian cells.

Screening rDNA

1. Gel Electrophoresis

2. Polymerase Chain Reaction (PCR)

Gel Electrophoresis

It screens rDNA by separating DNA fragments according to their size for DNA fingerprints. Scientists analyze the DNA fragments’ lengths and sizes.

Steps of Gel Electrophoresis

1. Gel is placed into the container as the power source is connected with the cathode on the side of the wells and the anode on the other side.

2. A DNA molecule samples of varying volumes are loaded into the wells.

3. The power is turned on as the DNA fragments migrate through the gel.

4. The fragments are separated by size.

Applications of DNA Fingerprinting

• Investigating crime scenes.

• Analyzing genes with an illness.

• Distinguishing different species.

• Analysis of antibiotic resistance.

• Study evolutionary relationships among species.

Polymerase Chain Reaction

It produces multiple copies of a DNA segment. Amplification of the expected product would confirm the presence of the gene within the samples.

Fields of Application for PCR

• Forensics

• Disease Diagnosis

• Research

• Medicine

• Food & Agriculture

• Phylogenetics

• Consumer Genomjcs

• Microbiology

Genetically Modified/Transgenic Bacteria

they have abilities that promote plant health and enhance substance degradation through genetic engineering

Genetically Modified/Transgenic Plants

These are usually from the development of crops with improved qualities that reduce waste from food spoilage

Genetically Modified/Transgenic Animals

biotechnology techniques help insert the genes into animal eggs