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Welcome to the World of
Biotechnology
An introduction into the business of
biotechnology for high school
students
Modified from a ppt found at https://www.georgiastandards.org
What is Biotechnology?
• Let’s break it down:
– Bio - alive or living
– Technology - the application of science to
achieve industrial or commercial objectives
• So basically, we’re talking about using
living materials for a commercial or
industrial purpose
– Taking living cells and putting them to work
for us!!!
A Definition That is a Little More Fun…
Origins of Biotechnology
• Although it seems like a new thing,
biotechnology has actually been around
a while
– Domesticated plants and animals are the
result of selective breeding (have you ever
seen a wild corn plant, not something you’d
want to eat)
– Using yeast to make bread rise
– Using bacteria or yeast to ferment grapes
into wine
So Why Should I Care?
• Biotechnology affects all aspects of your
everyday life, including: agriculture and food
safety, healthcare, law enforcement and
environmental issues
• Although there are many great career paths
involving biotechnology that you may consider,
possibly even more importantly, you will soon
be voters
– You’ll make decisions on the ethics involving
legalizing certain types of research
– You might be on a jury where biotechnology plays a
key part in the evidence presented
The Biotechnology Toolbox
• Today, biotechnology is used in three
main ways:
– Directly using cells
• Placing yeast into a bioreactor to ferment grapes
– Using the proteins/enzymes made by cells
• Isolating antibiotics from bacteria for use in
human medicine
– Using the genetic material inside of cell
• DNA profiling
Just Some of the Latest Advances in
the World of Biotechnology
• Cloning
• DNA profiling
• Genetically modified bacteria to synthesize
products
• Genetically modified foods
Cloning
• Creating a genetically identical copy of
something (ex. a DNA strand, a cell, an organ or
an entire organism)
• Single cells and DNA are fairly easy to clone
and so this has been done for a comparatively
long amount of time
• Cloning entire organisms becomes increasingly
more difficult the more complex the organism
is (ex. Humans are harder to clone than worms)
and so it is very recent and for some species
has not been perfected yet
How Cloning Works
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DNA is extracted from an adult (somatic) cell
An egg for this same species has it’s DNA removed
The empty egg is filled with the adult DNA
An electrical current is applied to the egg
The egg is implanted into a surrogate mother
The baby born from this egg is genetically identical
to the adult from which it was cloned
– But, it will not share any characteristics that aren’t
genetic
– It will not be the same age as the animal it was cloned
from (it’ll be a baby)
Cloning
Cloning
There are two VERY different types of cloning:
Reproductive cloning
Molecular cloning
gene 1
gene 2
Use to make two identical
individuals
Use to study what a gene
does
Very difficult to do
Routine in the biology labs
Illegal to do on humans
Reproductive cloning
cell from the body
take the nucleus
(containing DNA)
egg
remove nucleus
and take the
rest of the cell
Clone
identical to the individual
that gave the nucleus Dolly the sheep
Dolly the sheep was the first cloned mammal. To
make Dolly, scientists took the nucleus out of a
normal cell from a sheep. They put that nucleus into
an egg cell that had no nucleus. They then had a
new cell. This process is called Somatic Cell
Nuclear Transfer (SCNT)
Reproductive cloning
cell from the body
take the nucleus
(containing DNA)
egg
remove nucleus
and take the
rest of the cell
Clone
identical to the individual Dolly the sheep
that gave the nucleus
To make the new cell start to divide and grow, they gave
it an electric shock. Then it started to divide and
develop into an embryo. When it had grown into a very
early stage embryo called a blastocyst – a ball of just
50-100 cells – it was implanted into the womb of another
sheep so that it could grow into a lamb and be born.
Reproductive cloning
cell from the bodyegg
take the nucleus
(containing DNA)
remove nucleus
and take the
rest of the cell
Clone
Dolly the sheep
identical to the individual
that gave the nucleus
The new sheep is a clone of the sheep from which the nucleus was
taken at the start of the process. Both sheep have the same DA.
Not only sheep have been cloned. Scientists have now cloned
many different animals, including mice, cats, dogs, frogs, goats,
horses, pigs, rabbits and others. However, it is a difficult process
and does not always work. It is illegal to clone a human being in
this way.
Molecular cloning: Principles
1) Take DNA out of the nucleus
gene 1
cell 1
gene 2
cell 2
Molecular cloning is a process used by scientists
to make copies of a particular gene or genes
inside a cell. They use the technique to find out
more about what certain genes do or how they
work. Molecular cloning is done routinely in
laboratories today. It involves several steps:
1)Take the DNA out of a cell.
Molecular cloning: Principles
2) Make a new piece of DNA
gene 1
gene 1
gene 2
gene 2
2) Cut out the gene you are interested in (gene 2 in
this example). Insert it into a strand of DNA taken
from another cell. The gene is not literally cut out
with a knife or scissors – carefully chosen enzymes
break the DNA chain at particular points. More
enzymes are used to insert the gene into another
piece of DNA at exactly the right place (in this
example, next to gene 1).
Molecular cloning: Principles
3) Put new DNA into a test cell and grow copies
gene 1
Daughter cells
contain same DNA:
gene 2
insert new DNA
cell divides
Genes 1 and 2 have
been cloned
3. Once you have made a piece of DNA containing the
gene you want to study, put your new DNA into a test
cell. When the cell divides, it makes copies of itself.
Each new daughter cell contains an exact copy of the
DNA in your test cell, including genes 1 and 2. The
genes have therefore been copied and we say they
have been cloned.
Molecular cloning: Principles
This is a simplified description of the technique. There are some
intermediate steps involved and the details of the technique can vary,
but this scheme illustrates the key principle, i.e. we are able to make
cells containing particular genes in order to find out what those genes
do. Some examples of how this technique can be used are given on
the next slide.
1) Take DNA out of the nucleus
gene 2
gene
cell 1
cell 2
1
2) Make a new piece of DNA
gene 1
gene 1
gene 2
gene 2
3) Put new DNA into a test cell and grow
copies
gene 1 gene 2
insert new DNA
cell divides
Daughter cells
contain same DNA:
Genes 1 and 2 have
been cloned
Molecular cloning: Applications
Molecular cloning is an important tool used by scientists to
learn more about the roles of genes in development and
disease. Some examples of how molecular cloning can be used
in the lab are:
Loss of function (often called “gene
knockout”): a common technique that
Loss of function
remove a gene to see if has been very useful in helping
scientists understand how particular
anything works
genes are involved in disease.
differently
eye
Normal mousegene A
embryo missing
gene is involved in
giving the eye its colour
A gene is removed or blocked so that it
does not work, and then scientists watch
to see what happens.
This has been of such wide benefit for
science and medicine that the scientists
who developed this technology were
awarded the Nobel Prize for Medicine in
2007.
Molecular cloning: Applications
Reporter gene
add a gene
that shows
us when
another
gene is
working
gene is
active in
blue areas
only
Reporter gene: this generally involves using
colour to help scientists easily see when a
particular gene is working. A ‘reporter gene’ is
added to the DNA of cells.
This reporter gene makes the cells produce a
coloured protein – for example, a blue protein.
The reporter gene is put into the cells’ DNA
right next to another gene (gene x) that
scientists really want to investigate.
Wherever gene x is active (or ‘switched on’) in
a cell, the reporter gene is also active. This
means the cell makes the blue protein and
looks blue. So, it is easy to see which cells
have an active gene x because those cells are
blue.
Molecular cloning: Applications
Lineage tracing: this involves
looking to see what happens to a
cell’s daughter cells, and their
daughters, in a developing animal.
First, some cells are marked by
giving them a gene that scientists
can easily see working, e.g. a gene
to make a protein that is a
fluorescent green colour. This makes
the cells look green.
Every time the cells divide, their
daughter cells inherit the gene for the
green protein, so the daughter cells
Lineage tracing
mark a group of
cells to see where
their daughter
cells end up
gene is passed on
to cells all over the body
Why Clone?
• To create identical cells for research
purposes
• To maintain a genetically desirable
species of plant or animal
• To create a missing organ or tissue for
treatment of human diseases
• To save endangered or extinct species
Some Products of Cloning
DNA Profiling
• Identifying the pattern of certain sequences in parts of a
person’s DNA to determine if two samples come from
the same person, related persons or two, non-related
individuals
• Only parts of the DNA sequence are used because the
whole genome is too long to sequence repeatedly
• Everyone has a unique sequence of DNA (even identical
twins, although their genomes would be very close to
identical)
• In order to be an effective tool, we need to get DNA
from many people to determine how often certain
patterns show up in the population
How DNA Profiling Works
• The DNA is isolated from a cell sample and many
copies are made with a process called Polymerase
Chain Reaction(PCR)
• The DNA is cut into pieces using restriction
enzymes (they cut only at specific sequences)
• The DNA is run on a gel electrophoresis to separate
the pieces (separated based on size)
• Probes are used to find certain DNA sequences
(usually VNTR sequences)
• Comparisons of these pieces of DNA are made to
determine identity or relationships
What Does a DNA Profile Look Like?
What can DNA profiling be used for?
• To determine if a suspect was at a crime
scene
• To identify a murder victim
• To identify a soldier killed in the line of
duty
• To determine identity
• Paternity/maternity tests
Genetically-Modified Bacteria
• Inserting new genes into a bacteria to
trick it into making a product for us
• Although each bacteria usually doesn’t
make much product, millions of bacteria
can be grown in bioreactors at the same
time, and the product harvested from all
of them at once
How are Genetically-Modified Bacteria
Created?
• A piece of DNA containing the gene for the
desired product is cut with restriction enzymes
• A plasmid (circular bacterial DNA) is cut with
the same restriction enzyme
• The piece and the plasmid are ligated (fused
together)
• The plasmid is transformed into the bacteria
• The plasmid either stays in whole or the gene
crosses over into the bacteria’s DNA
What Does the Process of Bacterial
Transformation Look Like?
Some Products Now Synthesized by
Bacteria
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Biodiesel fuel
Chemicals to block an HIV infection
Photographs
Human insulin for diabetics
Plastics
Genetically-Modified Multi-Cellular
Organisms
• Livestock or produce that has received new
genes to make the product healthier, resistant
to pests or durable for travel
• The process is similar to that used to create
genetically-modified bacteria, but the genes
are being inserted into multi-celled organism
instead
How GMO are made
• The process varies slightly between each
species, particularly between plants and
animals, however some aspects are the same
• Changes are made to the organism’s DNA by
inserting a useful gene into the egg cell
• This changed egg is then implanted into a
mother and the baby born hopefully has the
desired trait
Some Genetically Modified Organisms
(GMO)
Why make GMOs?
• To give plants resistance to certain pests
without the use of pesticides
• To make plants drought resistant
• To make cows that produce more milk
• To make vegetables that can undergo long
transport without over-ripening
• To make chickens that contain extra vitamins
that may be missing from our diets
Bringing a Product to Market
The Ethics of Biotechnology
• Despite all the exciting things that biotechnology
can do or will do in the near future, there are
things to consider:
– Would it be ethical to clone a human? Why or why not?
– Should your insurance company be allowed to have
access to your DNA profile if it detected some disease?
– How can the bacteria in bioreactors be disposed of once
they are no longer useful?
– What happens to the natural balance when GMO are
sent out to compete with natural plants in the
environment?
Conclusion
• We are at the cusp of an exciting time in the
world of biology
– We are capable of manipulating living cells in ways
that would have been unimaginable even 20 years
ago
– With this new technology comes many new jobs
and benefits to mankind
– With this new technology comes the need to think
through the ethical issues that arise and to wisely
weigh the benefits against the drawbacks to make
informed decisions as to what research should be
encouraged and what should not