Download Biotechnology

Biotechnology
You Will Learn About…
•Transformation
•Cloning
•DNA Fingerprinting by
Restriction Fragment
Length Polymorphism
(RFLP)
•What is the name of the
lamb?
Brainstorm
• What are some ways in which DNA can be
used as a tool (think about TV, the news…)
Goals of Applied Genetics
1. Help humans create crops that can be frost
resistant (we love our peaches!)
2. Use transgenic organisms to help medical
researchers model human physiology for
testing
3. Help industry to create bacteria to break
down pollutants into harmless products
4. Pharmaceutical companies use recombinant
DNA to cheaply produce human hormones
(insulin) and other proteins
5. Help solve crimes and determine relatives
Technologies Addressed in this Show
please write these on first slide
– Bacterial Transformation
– Cloning
– DNA fingerprinting (RFLP analysis)
Selective breeding
• Selecting organisms with the most desirable
traits
• Requires time and several generations to
produce offspring with the desired trait
• Ex:
–
–
–
–
Short vs long haired cats
Milk production in cattle
Disease resistant foods
Bacteria that break down oil
Bacterial
Transformation
• Also called recombinant DNA
technology or gene cloning
• Uses a bacterial host because
of fast reproduction and a
circular DNA vehicle to hold
the foreign DNA=plasmid
• Organisms containing
recombinant DNA or foreign
DNA are known as transgenic
Steps involved:
1. Select the desired gene(s) to be inserted
into the organism and a bacterial host
containing a plasmid (vehicle to hold the
desired gene)
2. Cut two DNA molecules into fragments
with special (restriction) enzymes
3. Splice (rejoin) the fragments (gene and
plasmid) together in the desired
combination
4. Introduce or insert the new DNA into a
living cell for replication (mitosis)
= Vector to transfer DNA
Enzymes
•
•
Restriction Enzymes Used to cut a
DNA molecule at a specific nucleotide
sequence
Produces one of two types of DNA
fragments
1. Sticky ends (palindrome)
2. Blunt ends
Sticky Ends
(palindrome)
Blunt ends
Gene Cloning
• Used to produce genetically identical copies
of a cell, tissue, organ, and/or organism
• Needed to produce multiple copies of the
desired DNA
Cloning Applications
Currently
• Plants are cloned to produce a large
number of genetically identical plants
in a short amount of time
Future
2. Clone productive and healthy animals
to increase yield for farmers and to
grow organs for transplants
How cloning works….
Gene Therapy
• The insertion of normal genes into human
cells to correct genetic disorders like cystic
fibrosis. (Not successful yet?)
DNA Fingerprinting
(RFLP Analysis)
1. Obtain a small sample of DNA
2. Make millions of copies using PCR
(polymerase chain reaction) technique
3. Cleave (cut) DNA with restriction
enzymes
4. Separate DNA fragments using gel
electrophoresis and compare
5. Each human’s DNA will have some
unique pieces because each of our DNA
is unique
Gel Electrophoresis
• Gel electrophoresis is used to create a DNA
fingerprint
• Small amounts of DNA are loaded into wells
in the gel.
• An electric current pushes the small pieces of
DNA farther down the gel than the larger
pieces.
• DNA patterns are compared to known
patterns (Human Genome Project).
• Used for forensics, blood samples, and
paternity tests (children get half their bands
from mom and half from dad)
Running a gel…
How DNA moves…
Step 1:
Make wells in gel.
Step 2:
Pipette DNA into wells.
Step 3:
Run an electric current
to watch
DNA
migrate.
Step 4:
Notice similarities
and differences
in banding
patterns.
The Human Genome
Project
• There are approximately 25,000 genes on the 46
human chromosomes (far fewer than expected)
• Human Genome Project- an international effort to
completely map and sequence human chromosomes
(completed April 2003)
• This has been important in
– identifying genes that are related to disease.
– Determining human relationships with other
species.
Microarray
• An new technology, the microarray, allows
a cell to be samples for many genes at once.
• It is involved in finding
– What genes are important in cancer and cancer
prevention.
– What medicines can be used for a person
(customized medicine)
– Much more, and we will spend some time with
this.