Genetic Engineering &
Biotechnology
Major Techniques
• PCR –
• Polymerase Chain Reaction
• Restriction Endonucleases and Gel
Electrophoresis
• DNA Profiling/DNA Fingerprinting
• Gene Transfer: Transformation
Outline the use of Polymerase Chain
Reaction (PCR) to copy and amplify minute
quantities of DNA –Specifics not required
• Used to make millions of copies of select section of
DNA
• When small amount of DNA are found but large
amounts are needed for analysis
• Semen, blood, other tissues, long-dead specimens –
DNA from all can be amplified
• Thermus aquaticus – hot springs bacterium
• http://www.dnalc.org/ddnalc.org/resources/pcr.html
STATE that in gel electrophoresis
fragments of DNA move in an electric field
and are separated according to their size
• Separate DNA, proteins or other
molecules based on charge and size
STATE that gel electrophoresis is used
in DNA Profiling/Fingerprinting
Describe the application of DNA
Profiling to determine paternity and also
in forensic investigations
• CSI
• Paternity
• CDC – epidemiology: disease
transmission
• Geneology
• Breeding authenticity
Analyze DNA profiles to draw conclusions
about paternity or forensic investigations
STATE that,
• when genes are transferred between
species, the amino acid sequence of the
polypeptide translated from them is
UNCHANGED because the genetic code
is UNIVERSAL
Outline three outcomes of the sequencing
of the complete human genome
• HOMEWORK!
Organisms that have had genes
transferred into them from a different
species are GMOs or Transgenic Orgs.
Outline a basic technique used for gene transfer
involving plasmids, a host cell (bacterium, yeast or
other cell), restriction enzymes (endonucleases)
and DNA ligase
Outline a basic technique used for gene transfer
involving plasmids, a host cell (bacterium, yeast or other
cell), restriction enzymes (endonucleases) and DNA
ligase
• Messenger RNA coded for insulin is extracted from human pancreas
• DNA copies of the messenger RNA coding for insulin are made using
the enzyme reverse transcriptase.
• Plasmids: are small loops of DNA found in bacteria.
• Plasmids are cut open using restriction enzyme endonucleouse.
• The insulin gene and the plasmid are mixed.
• DNA ligase seals up the plasmid.
• The plasmid with the human insulin gene is called a recombinant
plasmid.
• The recombinant plasmid are mixed with a strain of E.Coli bacteria.
• The E.coli bacteria that pick up the plasmid start to make insulin
which is then extracted, purified and used by patients.
State 2 examples of the current uses of
GM-crops or GM-animals
• Ex. Golden rice - produces beta-carotene,
which can be metabolized into Vitamin A within
the body. Scientists hope that it will eventually
be a cheap source of beta-carotene in
malnourished countries, reducing the number of
children worldwide that go blind from Vitamin A
deficiency.
• Bt maize is a genetically modified corn crop that
produces a toxin that kills European corn borers
feeding on the maize
GM-animal examples
Cats,
Researchers took skin cells
from Turkish Angora
female cats and used a
virus to insert genetic
instructions for making red
fluorescent protein.
What’s the point of creating
a pet that doubles as a
nightlight? Scientists say
the ability to engineer
animals with fluorescent
proteins will enable them to
artificially create animals
with human genetic
diseases
Goats,
Strong, flexible spider silk
is one of the most
valuable materials in
nature, and it could be
used to make an array of
products — from artificial
ligaments to parachute
cords .
Researchers inserted a
spiders’ dragline silk gene
into the goats’ DNA in
such a way that the goats
would make the silk
protein only in their milk.
This “silk milk” could then
be used to manufacture a
web-like material called
Biosteel.
Chickens
GM hens - produce cancerfighting medicines in their
eggs. Human genes have
been added to their DNA so
that human proteins are
secreted into the whites of their
eggs, along with complex
medicinal proteins similar to
drugs used to treat skin cancer
and other diseases.
What exactly do these
disease-fighting eggs contain?
The hens lay eggs that have
miR24, a molecule with
potential for treating malignant
melanoma and arthritis, and
human interferon b-1a, an
antiviral drug that resembles
modern treatments for multiple
sclerosis.
Discuss the potential benefits and
possible harmful effects of one
example of genetic modification
HOMEWORK
Define – Clone:
• Clone: a group of genetically identical
organisms or group of organisms derived
from a single parent (in nature it is called
Asexual Reproduction)
Outline a technique for cloning using
differentiated animal cells
•
Udder cells are taken from a
donor sheep. The genes in the
cell are made dormant.
•
Unfertilized eggs are taken
from another sheep.
•
The nucleus is removed from
the egg cell.
•
The egg cell without a nucleus
is fused with the udder cell
using a pulse of electricity.
•
The fused cells develop into
zygotes.
Inserted back into mother.
•
Discuss the ethical issues of
Therapeutic Cloning (TC) in humans
• TC is the creation of an embryo to supply
embryonic stem cells for medical use. The
embryo does not survive the
process…only its stem cells do.
• You should be able to discuss the ethical
implications