Transcript Slide 1
What is it?
Selective breeding
among live stock
and even dogs
have been around
since the
beginning of
time. Using
microbes to make
food and drinks
Charles Darwin
1809-1882
natural selection
Gregor Mendel
1822-1884
genetics (pea plants)
Selective breeding has been around since the
beginning of time
Humans have selected particular traits and bred
organisms to have these traits
Don’t we as humans use selective breeding when
selecting our mates?
Complete The Genetic Technology worksheet front
and back
The driving force behind DNA technology we have today.
13 yr long research project completed in 2003 where scientist
from around the world tried to identify the 20,000-25,000 genes
in the human DNA and find the sequences of the 3 billion
chemical base pairs
Directors of the HGP are hoping that the information gained will
help make advances in biotechnology fields.
At least 350 biotechnology-based products resulting from the
Human Genome Project are currently in clinical trials.
http://www.ornl.gov/sci/techresources/Human_Genome/project/timeline.shtml
Agriculture
2. Medicinal
3. Forensics
1.
Biotechnology and
Agriculture
http://www.youtube.com/watch?v=qn52Ed1q4rk
Genetic Engineering The process of
altering the genetic material of cells or
organisms to allow them to make new
substances.
We can do this because
DNA is the same from
One organism to nextJust a little different order of bases.
GMO – genetically modified organism
Organisms that have acquired one or more genes
artificially
Transgenic organisms –
organisms that have acquired a gene from another
species or organism
ex – “super mice” in 1980’s used this in mice so that they
could produce a human protein needed for clotting.
Biotechnology and food
Videos:
Cons:
http://www.youtube.com/watch?v=1H9WZGKQeYg
Pros:
http://www.youtube.com/watch?v=cit1LBHThy4
Healthier farm animals
Pest resistant plants – so grow more food
Temperature, drought resistant, other environmental conditions
allow us to grow food where we couldn’t before creating greater
genetic diversity in different regions.
May have an increase in nutrient value
Ex. India – 1992- salinity resistant crops (rice / wheat) has allowed
people to grow these in areas that would not normally sustain
crops.
Ex. Golden rice – transgenic variety created with more beta carotin
that could help prevent vitamin A deficiencies that lead blindness
in poorer nations
New allergies may develop with these plants
Pollen from GMO’s can spread to wild species and
change their genetics
Unpredictable health effects – only been around since
1990’s so we do not know long term effects yet
Insufficient government regulation – GMO’s are not
mandatory to label in grocery stores – yet
May create unwanted effects in soil or surrounding
water supplies (ground water)
1. Gene therapy
Alteration of afflicted individual’s genes for therapeutic
reasons.
Try to supplement or replace a defective gene causing
the disease by inserting a normal allele into cells of
tissues that have the disorder.
For this to be permanent, the allele would have to be
transferred into cells and multiply throughout life.
They are trying to a achieve this for blood and immune
disorders. Using bone marrow cells which contain stem
cells for all blood products and immune system.
Currently being used to cure genetic disorders
Specific DNA sequences are inserted to try to replace
fully or absent genes so that gene expression can occur
The most effective way to is to using viruses to insert
the gene sequences into cells.
Why viruses? Any ideas?
All viruses naturally insert their genetic material into
their host cell as part of the replication cycle
http://www.youtube.com/watch?v=imL1Zmi3mWk
2. Diagnose Disease:
DNA technology used today to diagnose diseases even
before birth.
3. Vaccines
A mutant of the pathogen (virus / bacteria) used to
stimulate our immune system to create defense against
the pathogen
Some are genetically modified to be better.
Genetically altered crops are now grown that can
synthesize certain vaccines and eaten by
Gene therapy different ways to fight cancer:
Inject cancer cells with special genes that make the
tumor more receptive to cancer drugs
Place multi drug resistant (MDR) genes into the bone
marrow to make stem cells more immune to side effects
of anticancer drugs. (this preserves more red blood cells
for the patient and they are less tired as they go through
treatment)
Recent research is looking a genetically altering a
person’s T cells (ones that give us immune memory) to
be cancer specific. Find and recognize cancer and kill it.
The good thing about this is that it should last a lifetime
due to the “immune memory” of the T cells.
Complete DNA Medicine worksheet
Read and complete questions about Genetic Testing
Read Scientific American article:
Gene-Therapy Successes Spur Hope for Embattled Field
By Erica Check Hayden
http://www.scientificamerican.com/article/gene-therapysuccesses-spur-hope-for-field/
Scientific analysis of evidence from a crime scent to be
used in investigations or court of law
1. DNA profiling;
Can get DNA from any body fluid, small pieces of
tissue, hair, etc… left at the crime scene
used to prove paternity
Used to identify victim of a crime
Ex. World trade center nearly ½ of victims identified by
DNA analysis
Get DNA fingerprint activity from Lambert
Therapeutic hormones such as insulin and human
growth hormone are made by modified bacteria.
Until now, insulin was recovered from slaughtered pigs
and cattle. Now can genetically modify bacteria to
produce human insulin.
In past HGH recovered from cadavers, now bacteria
with modified DNA fragments chemically synthesize
HGH to help with dwarfism or other height deficits.
How Genetic Engineering Works:
Recombinant DNA technology
When DNA from two different organisms is
joined
1) Isolate the desired DNA and plasmid
Plasmid small rings of DNA
2 ) A restriction Enzyme is used o cut the DNA
into fragments
3) Sticky ends hold the plasmid and DNA
together until enzyme DNA ligase joins them
4) The recombinant bacterium is inserted into
a host bacterium
5) The bacterium then reproduces, the desired
DNA is identified using a probe
Probe – a strand of RNA labeled with a
radioactive element or fluorescent dye
Gene Splicing The process in which
fragments of DNA from one or more different
organisms are combined to form recombinant
DNA
http://www.youtube.com/watch?v=rjqaPSWAYY8
Take a look at the virtual lab
For homework complete the lab and print your results
Need to an example the works
http://glencoe.mcgrawhill.com/sites/dl/free/0078759864/383937/BL_22.html
Process of producing a genetically identical copy of a
living organism.
Occurs naturally in bacteria during asexual
reproduction
Types of artificial cloning
1. Gene cloning
2. Reproductive cloning
3. Therapeutic cloning
Copies of genes or segments of DNA
Used by scientists to make copies of genes they wish to
study
Process:
Isolate DNA from organism
Isolated DNA is cut at the gene you want (by enzymes) and
creates “sticky ends”
This gene can then be “glued” into plasmids of a bacteria or
virus
After gene is inserted the bacteriais allowed to multiply and
each time it multiplies, the gene they would like to study
also multiplies.
They now have multiple copies of this gene to work with.
Copies an entire organism
Process:
Remove somatic cell (skin cell) from an animal being
cloned
Transfer the DNA of the somatic cell into an egg (DNA
removed from egg)
Shock it with electricity to start dividing
The egg is allowed to develop and then implanted into
the womb of a surrogate mother.
Cloned animals may be used for testing new drugs or
treatments
Allows a uniform response because they are identical
Build endangered animals
Bring back extinct animals
Clone pets
Creating a cloned embryo for sole purposes of making
embryonic stem cells
These cells can be used in experiments to understand
diseases and develop new treatments
Philosophical Issue:
Stem cells come from blastocysts (embryonic stem
cells 5 days after the cells start to divide).
Cells harvested from cloned embryo, which results in
the destruction of embryo.