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Chapter 15
Until recently, scientists could not
modify the genetic code of living
things.
 They were limited by the variation that
exists in nature.
 Today scientists can go right to the
genetic code and re-write an
organisms DNA, transfer genes at will
from one organism to another, and
design new living things to meet
specific needs.

Biotechnology is the
commercial application of
biological products.
It is a wide ranging scientific
field which includes the
manipulation of living
organisms that results in new
products or processes by that
cell.
10,000 BC
Domesticating
Crops
6,000 BC
Brewing Beer
Domesticating Animals
8,000-9,000 BC
1880’s
Production of Vaccines
1940’s
Production of Antibiotics
1980’s Use of genetically modified organisms
Fields of Study:

Molecular Biology
- microbiology
- biochemistry
- cell biology

Molecular Genetics

Genetic Engineering: Moving a gene
from one organism to another
- chemical engineering
- biomanufacturing
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Humans use selective
breeding to pass desired traits
on to the next generation of
organisms.
Hybridization – The crossing
of dissimilar individuals to
bring together the best of both
organisms.
◦ Hybrids
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Inbreeding is the continued
breeding of individuals with
similar characteristics.
◦ Pure breeds
Inbreeding
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The goal is to maintain the desired
characteristics of a line of organisms.
There are higher occurrences of genetic
mutations in inbred species.
Because most members of a species are
genetically similar, there is a chance that a
cross between two individuals will bring
together two recessive alleles for a genetic
defect.
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Breeders can increase the genetic variation in
a population by inducing mutations.
You can increase the mutation rate using
radiation and chemicals.
Most mutations can be harmful but sometimes
they can bring desirable characteristics.
•Scientists increase the
rate of mutations in
bacteria using radiation
or chemicals in an
attempt to breed helpful
bacteria.
•Ex. Oil digesting
bacteria
•Drugs prevent separation of
chromosomes during meiosis
resulting in plants with
double or triple the
chromosome number called
polyploids.
•These plants are desirable
because they are larger and
stronger.
•Ex. Oat, peanuts, bananas
Manipulating DNA
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Until recently, scientists could not modify
the genetic code of living things.
They were limited by the variation that exists
in nature.
Today, scientists can manipulate the DNA of
organisms.
Scientists can go right to the genetic code
and re-write an organisms DNA, transfer
genes at will from one organism to another,
and design new living things to meet
specific needs.
Steps to Manipulating DNA
1.
2.
3.
4.
Cut the DNA.
Find the desired gene.
Copy the gene sequence.
Manipulated DNA sequence is ready for
application.
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DNA is large and must be cut up into smaller pieces that
can easily be read and utilized.
Restriction enzymes are used to cut DNA into more
manageable restriction fragments.
Find the Desired Gene
• Scientists use the Southern Blot method to find a
specific gene among millions of DNA restriction
fragments.
• Once a gene is found it is added to the genome
database.
Copying the Gene Sequence
 Polymerase Chain Reaction (PCR) is a technique
used to make many copies of a desired gene.
 Steps to PCR
1. DNA strands are separated by heating.
2. Short pieces of DNA, called primers, are
attached to the DNA strands to prepare a
place for DNA polymerase to start copying.
3. These copies serve as templates for more
copies.
Polymerase Chain Reaction
DNA
 Polymerase
Chain
PrimersReaction (PCR) is a technique
parent
Copies
are
usedstrand
to make
many copies
is
are of a desired gene.
attached.
separated.
made.
 Steps to PCR
1. DNA strands are separated by heating.
2. Short pieces of DNA, called primers, are
attached to the DNA strands to prepare a
place for DNA polymerase to start copying.
3. These copies serve as templates for more
copies.
Changing DNA

Recombinant DNA Technology
 Joining together DNA from two or more sources.
 This makes it possible to change the genetic
composition of living organisms.
 DNA of one organism is extracted and cut into pieces.
 A piece that produces a desired protein is inserted into
another organism’s DNA.
 The organism with the new piece of DNA produces the
desired protein.
Plasmids and Genetic Markers
• Bacteria are commonly used in Recombinant DNA
technology because they contain a circular piece of
DNA, called a plasmid, in addition to their own
chromosomes.
• Joining DNA to a plasmid, and then using the
recombinant plasmid to transform bacteria, results in
the replication of the newly added DNA along with the
rest of the cell’s genome.
• Plasmid’s contain genetic marker’s which make it
possible to easily identify the recombined plasmid
amongst millions of cells.
Transgenic Organisms

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Transgenic organisms can be produced by the
insertion of recombinant DNA into the genome of
a host organism.
Genetic engineers can now produce transgenic
plants, animals, and microorganisms.
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Cloning is the creation of genetically identical
organisms.
A clone is a member of a population of genetically
identical cells produced by a single cell.
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First cloned mammal to
survive.
277th attempt.
“Dolly” was an
important break
through.
She was euthanized at
age 6 because she was
suffering from lung
cancer and cripling
arthritis.
1. Remove the nucleus of an egg
2. Fuse egg with a cell taken
from another organism.
3. Place in the uterus of a foster
mother.
4. Foster mother gives birth to
cloned baby.
Donor Nucleus
These two cells are fused
using an electric shock.
Fused Cell
Egg Cell
The nucleus of the egg cell is removed.
An egg cell is taken from an adult
female sheep.
The embryo develops normally into a
lamb—Dolly
Embryo
The embryo is placed in the uterus of a
foster mother.
The fused cell
begins dividing
normally.
 Cows
 Pigs
 Mice
 Cats
 Dogs
 Horse
 Monkey
 First
 “CC”
cloned cat
Nucleus Donor
Egg Donor
Surrogate Mother
Cloned babies
 Dam
=
female
horse
 Will
be used
to study stem
cells and
animal to
human
transplants.

Scientists recently
announced that for
the first time, they
have successfully
cloned a rhesus
monkey embryo.
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Allow childless couple to have a child with their
DNA.
Tissues and organs for transplant.
Treatment of diseases like Alzheimer’s or
Parkinson’s.
Several copies of genetically altered cells.
Saving endangered species.
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Cloned animal’s have genetic defects.
Health problems.
Opposition to interference with reproduction.
Doctor’s playing “God”.
Many attempts would die.
Children born with severe deformities.
Trying to create Super humans.
Diminished self – esteem.
Currently - Fertility clinic in Texas using technology to
ensure male or female offspring.
 It
took nearly 300 tries on Dolly.
 Success rate of .4 on the horse.
 Success rate of 1.6 on the dog.
 How many humans would die
before this worked?
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Undifferentiated cells that can grow into
specialized cells.
A cell whose job is not yet determined. Other
cells “stem” from these types of cells.
Stem cells wait in the body until they get a
signal to differentiate into specific cells within
your body. Ex. Heart, skin, brain
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Adult Stem cells exist in adults, children, and
umbilical chords but in very limited numbers.
Not ideal for research due to low numbers and
due to the fact that some differentiation has
occured.
Embryonic stem cells have the highest
potential for research. A 4 to 5 day old embryo
called a blastocyt has a group of 150 or more
stem cells that have not yet differentiated.
Basically a blastocyt is a fertilized egg grown
in a petri dish.

member of a population of genetically
identical organisms produced from a single
cell

Ideally, genetic modification could lead to
better, less expensive, and more nutritious
food as well as less-harmful manufacturing
processes.

GM crops have become an important component of
our food supply.

Genetically modified foods are not regulated in the
United States. The FDA (Food and Drug
Administration) does not require labeling on
genetically modified foods.
Some examples of GM Animals include:
1.
Recombinant Bovine Growth Hormone
increases milk production in dairy cows.
2.
Pigs modified to produce more lean meat.
3.
Salmon injected with growth hormone to
grow faster.
4.
Chicken injected with estrogen which
increases breast size.
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Term used to refer to an organism that
contains genes from other organisms.
Organisms that have been genetically
modified.
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Mice susceptible to cancer for research.
Mice made to have human immune systems.
Livestock with growth hormone.
Chickens resistant to bacterial infections that
cause us food poisoning.
Mad cow resistant cows.
Sheep and pigs that produce our proteins.
Spider web goats.
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Mice susceptible to cancer
Mice made to have human immune systems
Livestock with growth hormone
Chickens resistant to bacterial infections that
cause us food poisoning
Mad cow resistant cows
Sheep and pigs that produce our proteins
Spider web goats
 Take
the gene
for making
spider web
silk
 Put
it in a goat
 Then milk it
 Extract the
spider web silk
in large
quantities…
 And we could
have…
 The
best
bullet proof
vest ever!
 Strongest
steel cables
 And much
more…
 Already
here, already
controversial.
 Here are some facts and
myths.
 25
percent of
corn is
genetically
modified.
 The
bulk of
both GM soy
beans and corn
is modified to
have a natural
insecticide.
Resist weed
killing chemicals.
 Organic farmers
sued farmers
using roundup
crops for fear of
contamination to
organic crops
and lost.
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The fish tomato and the
fish berry.
Genetically modify
plants to have a fish
gene that makes them
able to live in colder
temperatures.
Experimentally tested,
but never worked.

As more and more
farmers are
realizing the
efficiency of these
GM plants, the more
they will be used.
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Preventing Disease
◦ Provitamin A rich Golden Rice will hopefully prevent
problems caused by infant malnutrition.
◦ Transgenic plants and animals to produce human
antibodies.
◦ Transgenic sheep and pigs to produce human
proteins.

Medical Research
◦ Transgenic animals with human immune systems for
researching cures and organ growth for transplants.

Treating Disease
◦ Genetically engineered bacteria produce human
growth hormone, insulin, blood clotting factors,
cancer fighting molecules such as interleukin-2 and
interferon.
◦ Gene Therapy is the process of changing an absent
or faulty gene to treat a medical disease or disorder.
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A defective protein is replaced with a good one,
eliminating the symptoms of the disease.
Insertion of a new “healthy” gene into the organism
to provide needed (usually) proteins, hormones etc.
Gene is carried into the host by a viral
vector (like the flu virus) that has been disabled.
Can provide relief for many genetic diseases.
Gene therapy research is ongoing with cystic
fibrosis, gout, rickets, sickle-cell anemia, and
inherited high cholesterol.
Problems: immune responses to the virus,cancer
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Before: Diabetics had to use insulin from
cadavers.
Now: We make bacteria that produce human
proteins such as insulin, growth hormone,
clotting factor.
Future: Bacteria may produce substances to
fight cancer, make raw materials for plastic
and fibers.
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Diabetes is a disease in which the human
body doesn’t properly produce insulin.
Insulin is a hormone necessary to break down
carbohydrates in the blood stream for use in
cellular respiration.
No carbs for cellular respiration means no
ATP energy for cells.
Diabetics inject insulin into their bodies to
replace the insulin that is supposed to be
produced.
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Other animals?
Get something less cute to make it for us using
the gene for insulin.
Transformation
The gene for insulin is isolated and
removed from human DNA leaving it with sticky ends.
A plasmid from the bacteria E coli is removed and cut
open using restriction enzymes.
The insulin gene is inserted into the bacterial plasmid using DNA
ligase.
The recombinant plasmid is taken up by the bacteria by
transformation.
The bacteria reproduces, making copies of the gene
each time, allowing lots of insulin to be produced.
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Genetic Testing
◦ Now available for diagnosing hundreds of disorders.

Examining active genes
◦ Examining active genes in different cells helps
scientists to understand how cells function
normally and what happens when genes don’t
work as they should.
◦ DNA microarray technology enables scientists to
study thousands of genes at once to understand
their activity level.

Epogen,neupogen
(Amgen)
Anemia, chemotherapy
effects
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TPA, Insulin
(Genentech)
Blood clot remover,
diabetic treatment
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Interferon Beta
(Biogenidec)
Treatment of Multiple
Sclerosis

Algucerase
(Genzyme)
Gaucher’s Disease
lysosomal storage
genetic defect
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DNA fingerprinting
◦ Analyzes sections of DNA that may have little or no
function but vary widely from one individual to
another.
◦ These DNA samples can be separated using gel
electrophoresis.
◦ The number and position of bands formed on each
lane of gel is the actual genetic "fingerprint" of
that DNA sample.
◦ Each individual has a unique DNA fingerprint (except
for identical twins).
◦ DNA fingerprinting has revolutionized forensics.
◦ Paternity testing utilizes DNA fingerprinting.
Profits and Privacy
• Patenting Life
• Patent holders sometimes demand high fees that block
other scientists from exploring certain lines of research.
• Do you have exclusive rights to your DNA?
• Should you, like patent holders, be able to keep your genetic
information confidential?
• Should genetic sequences be patented?
• Genetic Ownership
• The United States Congress passed the Genetic Information
Nondiscrimination Act in 2008. The act protects Americans
against discrimination based on their genetic information.
EX. Health insurance companies, employers
Safety of Transgenics
• Pros of GM Foods
• Careful studies of GM foods have provided no scientific support
for concerns about their safety , and it does seem that foods
made from GM plants are safe to eat. (At least that is what the
companies marketing the products claim. The other side doesn’t
have enough money or the research facilities to undergo such
large scale research.)
• Cons of GM Foods
• GM foods are not required to undergo special safety testing
before entering the market.
• No additional labeling is required to identify a product as
genetically modified.
1.
Artificially introduced proteins may cause allergic reactions in
people with allergies.
2.
Recombinant Bovine Growth Hormone (rGBH) increases udder
infection causing milk to contain increased levels of pus, fat, and
bacteria. Antibiotics are given to the cows and then passed to their
milk and consumed by people causing antibiotic resistant bacteria
to thrive.
3.
rBGH causes increased production of another hormone which at
high levels can cause cancer.
4.
Herbicide and pesticide resistant crops are over sprayed with weed
killer causing everything but the crop to die. The crops then absorb
the weed killer which is passed on to the consumer who eats the
crop.
5.
Destruction of plant life surrounding the crops destroys the habitats
of many beneficial insects and the animals that survive on the
insects such as birds.
6.
Seeds of genetically modified plants are unable to reseed
themselves naturally so the farmer must purchase new seeds when
it is time to replant.
7.
GM foods have been linked to ADD, ADHD, earlier onset of puberty in
females, inability to concentrate, cancer, etc.
8.
The hormone estrogen is changing puberty and physical appearance
of male and female adolescents.
Organic foods are foods manufactured and
grown with no pesticides, hormones,
genetic modification, etc. They are all
natural.
Industries that market organic foods are
growing in popularity as more and more
people become aware of exactly what they
are consuming in a GM product.
However, organically grown products are often
smaller in size and more expensive.
Ethics of New Biology
• Just because we have the technology to modify and
organism’s characteristics, are we justified in doing so?
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There is an enzyme
that makes fireflies
glow
Luciferase
Could we take a
gene out of an
animal and put it in
something else?
Could we get things
that don’t glow, to
glow
 Put
luciferase
gene in a
tobacco plant
and you can
get a glowing
tobacco plant