DNA Manipulation Notes
DNA Manipulation
Diabetes
Genetic engineering
–Animals
–Drugs
Bacterial plasmids
Biopharming
Transgenic organisms
Knockout mice
Cloning
DNA Manipulation
Genetic engineering video notes
Cloning video notes
Diabetes
Diabetes mellitus is a disease caused by the inability to properly use insulin, resulting in elevated blood glucose levels
Many people require insulin injections to survive
Insulin allows glucose to be transferred from the blood into cells
Approximately 5% of all deaths are caused by diabetes.
Diabetes
Diabetes video notes:
Insulin Video notes:
Diabetes
Due to the need, actual human insulin is now mass-produced
Scientists insert the human insulin gene into bacteria, and the bacteria makes human insulin.
This genetic engineering, the intentional alteration of a genome by substituting or introducing new genetic material
Diabetes and Insulin
The human genome codes for insulin in inserted into an E. coliplasmid (small circular pieces of DNA)
The E. coli (bacteria) transcribes and translates the piece of human DNA to make the human protein insulin, which is then harvested from the bacteria and put into a container to be used.
Safflowers are also used to produce human insulin.
Genetic Recombination
The first step in genetic recombination is to isolate, or cut out, a DNA fragment that contains the desired gene.
You must also cut the circular plasmid (from the bacteria) to make it linear
Scientists use restriction enzymes which act like molecular scissors, cutting DNA molecule at specific locations.
Video notes: How Genes are inserted
Genetic Recombination
You then insert your DNA segment into a bacterial plasmid using DNA ligase
Let the bacterial plasmid replicate and mass produce your protein
–These plasmids used for transferring foreign genetic material into a cell are called vectors
Transformation
The successful introduction of DNA from another source is called transformation.
The cell that has received the DNA is said to be transformed.
The bacteria is said to contain recombinant DNA, which is a DNA strand that is created using pieces of DNA from two or more sources
Biopharming
Genetic engineering uses DNA technology to modify the genes of a cell or an organism.
Molecular biologists can introduce new functions into an organism.
Today, scientists use genetic engineering to find cures for various diseases that affect animals and plants.
Biopharming
Perhaps most useful is the introduction of one or more genes from one organism into another.
This could cause the host organism to produce a certain protein, such as insulin or clotting factors,that is useful to us. E.g. Allow us to become resistant to certain diseases, grow human organs, grow faster, etc.
When such pharmaceutical products are produced on a large scale, the process is called biopharming
Genetically Engineered animals video:
Medical uses for genetically engineered animals:
Transgenic Organisms: Altered DNA
An organism that has been changed by scientists to contain one or more genes from another organism is known as transgenic organisms or genetically modified organism (GMO)
VIDEO: Jimmy Kimmel!
Why Use Transgenic Plants and Animals?
Cost - animal and plant based methods are usually more economical (cheaper) than operating a laboratory with controlled bacterial populations.
Size – larger organisms can produce more stuff.
Transgenic Plants
Genetically modified (GM) canola and other field crops have been engineered to be resistant to specific herbicides.
–This technology means that herbicides can be sprayed to kill weeds but the crop plant remains healthy.
Farmers spend about 40% less on herbicides for GM canola crops versus conventional canola crops, and they report up to a 10% increase in yield.
Transgenic Plants
Video: How are GMOs Created?
Video: 5 Myths about GMOs
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Knockout Mice
Knockout mice are produced by genetic engineering to have at least one gene completely turned off by a mutation
They are used to study the purpose of each gene.
–If a gene is turned off, you can more easily see what it does. (Knocked out)
Cloning
Cloning is the process of making a genetically identical organism.
It has been used for many years to produce plants (even growing a plant from a cutting is a type of cloning).
The first cloned mammal (Dolly) was born in 1997
Since Dolly, several scientists have cloned other animals, including cows and mice.
Video: Cloning Dolly
Why Clone?
The main reason to clone plants or animals is to mass produce organisms with desired qualities, such as prize-winning apples or a genetically engineered animal that produces more milk, beef, etc.
Other reasons for cloning might include replacing human organs (no rejection or need of a donor because they are your organs) repopulating endangered or extinct species and building a clone army……thoughts?
Issues
Deciding exactly where to draw the line on transgenic organisms and cloning is difficult.
What is acceptable and what isn’t?
Do the ends justify the means?
Video: Careers in Genetic Engineering