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What is Genetic Engineering?
1.Genetic engineering is a laboratory
technique used by scientists to change the
DNA of living organisms.
2. It is also the alteration of an organism's
genetic, or hereditary, material to eliminate
undesirable characteristics or to produce
desirable new ones.

3. Genetic engineering
can be used to increase plant and animal
food production; to diagnose disease,
improve medical treatment, and produce
vaccines and other useful drugs; and to
help dispose of industrial wastes.
. Selective breedingallowing only those
animals with wanted
characteristics to produce
other generations
1
2. Hybridization (crossbreeding)the combining of different
species (members of the same
species with different traits) to
combine wanted characteristic
of both.
3. Recombinant DNAcombining DNA from
two different sources

Recombinant DNA technology is used to
isolate and study genes.
1.
A gene is located on the chromosome map.
(Restriction Enzymes & plasmids)
A DNA library of that organism is produced.
The “gene” of interest is isolated from the
library.
Multiple copies are produced for study. (PCR)
2.
3.
4.
 Cutting DNA 
Cutting DNA~ Most DNA molecules are too
big to be analyzed, so they have to be cut into smaller
pieces. Scientist cut them using restriction enzymes.
Restriction enzymes cut specific sequences of
nucleotides.
EX: EcoRI, one of many restriction
enzymes, is obtained from the bacteria
Escherichia coli.
 Cutting DNA 
 EcoRI Surrounds the DNA molecule at the
point it seeks (sequence GAATTC).
 It cuts one strand of the DNA double helix at
one point and the second strand at a different,
complementary point (between the G and the
A base).
 The separated pieces have single stranded
"sticky-ends," which allow the complementary
pieces to combine.
Restriction Enzymes are Enzymes That Cut DNA Only at
Particular Sequences
Restriction
enzyme
animation
The enzyme EcoRI cutting DNA at its recognition sequence
Different restriction enzymes have different recognition sequences.
This makes it possible to create a wide variety of different gene fragments.
Sample of Restriction Enzyme
EcorR1
Plasmids are Used to Replicate a Recombinant DNA
Plasmids are small circles of DNA found in bacteria.
Plasmids replicate independently of the bacterial chromosome.
Pieces of foreign DNA can be added within a plasmid to create a
recombinant plasmid.
Replication often produces 50-100 copies of a recombinant
plasmid in each cell.
Route to the
Production by
Bacteria of
Human Insulin
Overview of gene
cloning.
Cloning
animation
Examples of Recombinant DNA techniques:
 Food
production- Recombinant
DNA has been used to combat
problems in plant food
production: the destruction of
crops by plant viruses.
Fourteen month-old genetically engineered (“biotech”) salmon (left) and
standard salmon (right).
Genetically Modified Crops
Genetically Modified Cotton
(contains a bacterial gene for
pest resistance)
Standard Cotton
Examples cont….

Medicine- Recombinant DNA technology
also is used in the production of vaccines
against disease. A vaccine contains a form
of an infectious organism that does not
cause severe disease but does cause the
body's immune system to form protective
antibodies against the organism. When a
person is vaccinated against a viral disease,
the production of antibodies is actually a
reaction to the surface proteins of the coat of
the virus.
Examples…….
Cloning- Cloning is the creation of an
organism that is an exact genetic copy of
another. This means that every single bit of
DNA is the same between the two.

Reasons for cloning
1. Cloning for medical purposes
 Cloning stem cells for research
 "Pharming" for drug production
2. Reviving Endangered or Extinct Species
3. Reproducing a Deceased Pet
4. Cloning Humans?
Cloning
Clone- a member
of a group of
genetically
identical cells
 May be produced
by asexual
reproduction
(mitosis)

Animal Cloning
Dolly and her surrogate mother.
Pharming
Pharming is the production of pharmaceuticals in animals engineered to
contain a foreign, drug-producing gene.
These goats contain the human gene for a clot-dissolving
protein that is produced in their milk.
D N A
Changing the DNA code of
living organisms is referred to
as
Genetic Engineering…
 DNA extraction~ this is the process DNA
is taken from the cells, proteins are broken
down, and DNA is separated from the cell
DNA Extraction
 Chemical
treatments cause cells
and nuclei to burst
 The DNA is inherently sticky, and
can be pulled out of the mixture
 This is called “spooling” DNA
Restriction enzymes cut
DNA at specific sequences
 Useful to divide DNA
into manageable fragments
DNA fragments can be separated through a process called
gel electrophoresis.
 DNA can be
separated based on
size and charge
 The phosphate
groups are negatively
charged
 DNA is placed in a
gel and electricity is
run through
Electrophoresis
Negative DNA
moves toward
the positive
end
 Smaller
fragments
move farther
and faster

Electrophoresis
*Copying Genes*
PCR or
Polymerase Chain
Reaction
allows scientist to
make several copies
of a specific gene.
What is DNA
Fingerprinting?
A technique used by scientists to
distinguish between individuals of the
same species using only samples of
their DNA
What is DNA Fingerprinting?



The chemical structure of everyone's DNA is the same.
The only difference between people (or any animal) is
the order of the base pairs.
Using these sequences, every person could be identified
solely by the sequence of their base pairs. However,
because there are so many millions of base pairs, the
task would be very time-consuming. Instead, scientists
are able to use a shorter method, because of repeating
patterns in DNA.
These patterns do not, however, give an individual
"fingerprint," but they are able to determine whether
two DNA samples are from the same person, related
people, or non-related people.
DNA Fingerprinting Basics
Different individuals carry different alleles.
Most alleles useful for DNA fingerprinting differ on the basis of the
number of repetitive DNA sequences they contain.
Uses of DNA Profiling
 DNA
profiling
is used to solve
crimes and
medical
problems
DNA, the Law, and Many Other Applications –
The Technology of DNA Fingerprinting
A DNA fingerprint used in a murder case.
The defendant stated that the blood on his clothing was his.
What are we looking at? How was it produced?
Example
A violent murder occurred.
 The forensics team retrieved a blood sample
from the crime scene.
 They prepared DNA profiles of the blood
sample, the victim and a suspect as follows:

Was the suspect at the crime
scene?
Suspects
Profile
Blood sample
from crime
scene
Victims
profile
Solving Medical Problems
DNA profiles can be used to determine
whether a particular person is the parent of a
child.
 A childs paternity (father) and maternity
(mother) can be determined.
This information can be used in
• Paternity suits
• Inheritance cases
• Immigration cases
Example:  A Paternity Test
By comparing the DNA profile of a
mother and her child it is possible to
identify DNA fragments in the child
which are absent from the mother and
must therefore have been inherited
from the biological father.

Is this man the father of the
child?
Mother
Child
Man