Class Notes
Biotechnology - Genetic
Engineering
Questions/Main Idea:
Name: _______________________________________
Period:_______________________________________
Date: _______________________________________
Notes:
Historical Technologies:
Applied Genetics
• Manipulation of the hereditary characteristics of an organism to
improve or create specific traits in offspring
– e.g., selective breeding, hybridization
What is selective
breeding?
e.g., dog breeds
• Selective breeding → Allowing only those individuals with the
desired traits to reproduce
What is hybridization?
e.g., commercial chickens
• Hybridization → crossing different individuals to bring together the
best traits of both organisms
– Produces hybrid offspring that are often hardier than the parents
What is genetic
engineering
• Altering an organism’s genetic code (DNA) to get it to express
desired traits
Examples of genetic
engineering
• Bacillus thuringiensis (Bt): a bacterium that produces a caterpillar
toxin
• The gene for this toxin has been inserted into this corn’s genome,
which causes it to produce the toxin
- Bt corn
- spider silk
• A spider’s silk-making gene has been inserted into a goat, which then
produces silk in its milk
- golden rice
• Daffodil genes for making beta-carotene are inserted into the genome
of rice
-- human insulin
• Previously, humans with diabetes used insulin derived from the
pancreas of cows and pigs (limited production)
• Today, most human insulin comes from human insulin-making genes
transferred into simple cells such as bacteria or baker’s yeast
(unlimited supply)
– Identical to insulin made by the human pancreas
Recombinant DNA in
bacteria
• Recombinant DNA → taking a piece of one DNA and combining it
with another strand of DNA
• Often, fast-growing single-celled organisms are used
–
e.g., bacteria
• A piece of DNA that codes for a protein we want more of (e.g.,
human insulin) is spliced into the DNA of the fast-growing organism
What is gene therapy?
• Gene therapy → adding a corrected copy of a gene to a person with a
mutated gene to treat a disease
– e.g., Cystic Fibrosis
• Does NOT change the person’s genetic code!
– Effect is temporary
Summary: