Download Genetic Engineering

Genetic Engineering
• Genetic Engineers are scientists who can
change the genetic code of an organism…
– With the help of ENZYMES & Special
Equipment
• OR… Your neighborhood farmer/breeder
– With the help of Mother Nature!
Several Different Types
• Selective Breeding
– Inbreeding (Remember the Royal Family?)
– Hybridization (Hybrid = 2 different “things”)
• Recombinant DNA
– Transgenic Organisms
• Gene Therapy
– Replace or repair incorrect DNA
• Gel Electrophoresis (DNA Fingerprinting)
Selective Breeding
• Allowing only
those organisms
with desired
traits to produce
the next
generation
• Remember
Mendel???
• People have been
using selective
breeding for
1000’s of years!
Honestly….
• How many different
types of tomatoes
do you think actually
grow NATURALLY?
• NOT as many as
they offer at the
local grocery store!
Let’s Talk Potatoes
• Luther Burbank –
Father of Genetic
Engineering
– Remember the Irish Potato
Famine?
Potatoes and Immigration????
• Between 1845 and
• Ireland's Great
1855 more than 1.5
Potato Famine of
1845 is seen by some million adults and
as a turning point in
children left
Ireland’s history
Ireland to seek
- Global Regents
refuge in America
Question!
• It impacted the
history of America
as well as Ireland
Father of Genetic Engineering
• Luther Burbank identified the
“blight” that infected the entire Irish
potato crop
• Remember, the potatoes of Ireland were
CLONES of each other… one disease wiped
out the entire crop in all of Ireland!
• Burbank created the first disease
resistant potato
• Now there are over 800 varieties!
Inbreeding -A type of Selective Breeding
• The continued crossing of
organisms with similar traits (often
closely related)
NOT A HEALTHY THING TO DO!
• This can cause all of the recessive
genes to produce traits which may not
be wanted/needed... including diseases!
– Remember the Royal Family & Hemophilia?
Remember the Royals…
•Inbreeding brings out OBVIOUS traits (like
the protruding chins above!) as well as
hidden (recessive) traits (like Hemophilia and
Porphyria!)
Inbreeding
Can bring out the worst….
Hybridization
(Making Hybrids)
• Crossing two different organisms to
get the best traits from both
– Remember? What is a hybrid car?
• How about PLUOTS?
– A cross between plums
and apricots???
Hybridization
• How about Labra-doodles?
• Or Cockapoos?
• Or Ligers?
Or
Pineberry?
Biotechnology
• Genes can be changed through
genetic engineering
• Scientists can insert genes into any
cell’s DNA!
– “Recombining” the DNA
• Called “Recombinant DNA”
• The cell will read the instructions and
make the protein
• The cell will also pass the new
instructions on to its offspring
How do we do it today?
• Gene Modification
• Changing (modifying) an organism's
genes
• Gene therapy is a
technique that uses
genes to treat
disease
• Allows doctors to
treat a disorder by
inserting a gene into
a patient’s cells
instead of using
drugs or surgery
– Replaces a mutated
gene with a healthy
copy of the gene
Gene Therapy
Different types of Gene
Therapy
Ashanthi
Cell Augmentation
In Vitro (“Germ” line therapy)
(After the Karyotype reveals
a disorder)
More Genetic Engineering
• DNA Extraction
• Opening the Nucleus to expose and remove
the DNA
• Cutting DNA
• Restriction Enzymes (act like scissors)
• Separating DNA
• Gel Electrophoresis
• Inserting Genes
• Gene Splicing (Again, using Enzymes!)
We do it ALL THE TIME!
• Today, we use bacteria to
produce hormones we need…
Why Bacteria?
Bacteria are Prokaryotes (NO Nucleus)
DNA is in cytoplasm
Plasmids are small circular Extra DNA…
We use Plasmids because they are small
and easy to manipulate (Called
“Vectors”)
• Plus, Bacteria replicate quickly!
•
•
•
•
Plasmids
We insert specific genes into the
bacterial plasmid… and then, the bacteria
makes the hormones we need…
Recombinant DNA
• This is called
Recombinant DNA
– Combining the DNA
of one organism
with the DNA of
another organism
• Making a Hybrid!
– We use Restriction
Enzymes to cut the
DNA and genes
• The act like scissors
Recombinant Bacteria
1.
Remove bacterial DNA
(plasmid)
2.
Cut the Bacterial DNA with
restriction enzymes
3.
Cut the DNA from another
organism with other
restriction enzymes
“restriction enzymes”.
4.
Insert the cut pieces of
DNA together put the
plasmid back into
bacteria
5.
The recombinant bacteria
reproduces
6.
The foreign genes will be
expressed in the
bacteria
Benefits of Recombinant Bacteria
Bacteria can make human insulin or human
growth hormone. (HUMAN!!!!)
Bacteria can be engineered to “eat” oil spills.
BP Oil Spill…
• BP Underwater Footage
Oil Eating Bacteria
The DNA of both plants and
animals can be changed!
• Disease-resistant
and insect-resistant
crops
• Hardier, larger fruit
• 70-75% of food in
supermarket is
genetically modified
(GMO)…
– But we don’t know it!
Plants
Genetically
Modified
Organism
Genetically modified organisms are
also called Transgenic Organisms
TRANSGENIC ANIMALS
Mice – used to study human
systems/medicines
Chickens – more resistant to
infections
Cows – increased milk supply
and leaner meat
Goats, sheep and pigs –
produce human proteins
in their milk
Transgenic Goat
Human DNA
in a Goat Cell
This goat contains a human gene
that codes for a blood clotting
agent. The blood clotting agent
can be harvested in the goat’s
.
milk.
What disorder would this blood
clotting agent be used for?
________________________
Bacteria in Vats…
Altering “Animal Organs”
• Pig hearts and heart
valves have been
genetically altered
and used to save
people with heart
disease
Cloning
• Cloned mice are
used to study
various human
diseases
• We’ll discuss
cloning later
Genetic Engineering and
Crime Scenes……
CSI is correct…. Kind of…
If it was alive… it had cells…
• If the specimen has cells, it has DNA!
• If it has DNA, it can be
“fingerprinted”!
Every person’s
DNA has a
specific
“Fingerprint”
(Banding
Pattern)
Gel Electrophoresis
• A Separation
Technique
• This technology
allows scientists to
identify someone’s
DNA!
Gel Electrophoresis
• A separation technique
– You’ve learned about a couple…
remember Chromatography & leaf
pigments???
• Gel Electrophoresis uses electricity
• Separates based on size!
– HA! Again!
– Size (and shape) are SOOOOO
important!
Gel, Electricity, DNA &
Restriction Enzymes
Steps Involved in Gel Electrophoresis
“Cut” DNA sample with
restriction enzymes
DNA fragments “run”
through a gel using
electricity
Bands will form in the gel
Everyone’s DNA bands
are unique – like a
fingerprint - and can
be used to identify a
person.
DNA bands are like “genetic fingerprints”
Crime scenes rely on DNA
evidence
This is DNA Fingerprinting
DNA Fingerprinting
Used for criminal and
paternity cases…
Which suspect is
linked to the crime
scene by DNA
Fingerprinting?
A, B, C or D?
DNA Fingerprinting - Criminal
DNA Fingerprinting-Paternity