Transcript GENETIC ENGINEERING (ppt)

GENETIC
ENGINEERING
GENETIC ENGINEERING
• The process of replacing specific
genes in an organism in order to
ensure that the organism
expresses the desired trait.
• Takes genes from one organism
and places into another
Where are the genes?
• Genome—refers to
all the genetic
material in an
organism
• A gene map—shows
the relative location
of each known gene
on a chromosome
How does it work?
• A single gene, a half page recipe in
the 52-thousand-page set of recipe
books, can
direct an
organism to
make new
traits or
remove them
CLONING
• Clones are exact genetic
copies…every single bit of the
DNA is identical.
• Clones can happen naturally—
identical twins
CLONING
• Cloning can
be done at
different
levels: gene,
therapeutic,
or organismal
What cloning isn’t…
What cloning is…
https://www.youtube.com/watch?v=IG36VsrKYF4
CLONING
STEM CELLS
• Undifferentiated
cells that have
the potential to
become
specialized
GENE THERAPY
• Scientists insert a normal
gene into an absent or
abnormal gene
• Once inserted, the normal
gene begins to produce the
correct protein or enzyme,
eliminating the cause of the
disorder
GMO
(GENETICALLY MODIFIED ORGANISMS)
• Genetically modified (GM)
foods possess specific traits
such as tolerance to herbicides
or resistance to insects or
viruses.
• What is the potential human
health impact? What is the
potential environmental impact?
What Have I Eaten?
GMO food list
By most estimates, up to 70%
of the processed foods at your
local grocery store contain at
least one ingredient that’s
been genetically altered
Genetically modified to travel
better so don’t have to be picked
when green – better tasting!
Genetically modified to
reduce being eaten by insects.
WHAT CAN
GENETIC
ENGINEERING
DO FOR US??
Hope to develop plants that:
• Can manufacture natural
insecticides
• Are higher in protein
• Spoil more slowly
Sounds nice, but:
• Insecticides kill most insects, but some
do survive…they have genes that are
basically immune to the poison
• To get rid of THOSE insects, we need
new poisons
THINK ABOUT IT…
There is so much poison
being used, people have
to wear protective suits!!!
And THEN you eat that
food!!!
Hope to develop animals that:
• Are bigger
• Are faster growing
• Are resistant to disease
• The bad…
• Farmers use antibiotics, and as
animals become resistant, they use
even more…
• This leads to decreased nutritional
value and an increase in antibioticresistant infections.
• And the ugly…
• Recombinant bovine growth hormones
(rBGH) are given to cows.
• rBGH is then found in milk products…
• Some studies have linked this
hormone to infertility and fetal
development problems (just from
drinking milk!!)
The milk even has PUS in
it—from the infections the
cows suffered from too
much hormone! (EWWW)
Hope to develop bacteria that:
• Produce hormones such as
human insulin or human growth
hormone
• But recently…
• Human insulin produced by GM
microbes have caused human
deaths! This is currently being
investigated by the FDA.
1. In people with cystic
fibrosis, one of the genes
is faulty and cannot do its
job properly.
2. To fix the problem, a
copy of the same gene
from a healthy person is
spliced into a virus.
3. The patient’s lungs are
infected with the virus. It
delivers the working gene
into the patient’s cells.
The cells can then make
the right protein, and the
patient can breathe
normally.
Patient’s cell
Patient’s DNA
Faulty Gene
Virus DNA
New working
gene
Patient’s DNA
Virus DNA with
new gene
SOUNDS GOOD BUT…There have been no safety studies for long term
effects of the genes. There could be unknown consequences…
Can We End World Hunger?
Malnutrition and vitamin deficiencies?
Golden rice is genetically modified rice
that now contains a large amount of Avitamins. Or more correctly, the rice
contains the element beta-carotene
which is converted in the body into
Vitamin-A. So when you eat golden
rice, you get more vitamin A.
Beta-carotene gives carrots their orange color and is the
reason why genetically modified rice is golden. For the golden
rice to make beta-carotene three new genes are implanted: two
from daffodils and the third from a bacterium
Can We End World Hunger?
Malnutrition and vitamin deficiencies?
The thought…
The rice can be considered a particular advantage to poor
people in underdeveloped countries. They eat only an
extremely limited diet lacking in the essential bodily
vitamins. The consequences of this restricted diet causes
many people to die or become blind. This is particularly
true in areas of Asia, where most of the population live on
rice from morning to evening.
In reality…
World hunger is a result of people not having access
to food. The world produces about 12 billion tons of
food per year, but only 7 billion tons are being
consumed. Essentially, about 1/3 of our food supply
is being wasted…GMOs aren’t going to help that!!!
Fast-growing salmon
• AquaBounty’s genetically modified salmon grows twice as fast as the
conventional variety — the photo shows two same-age salmon with the
genetically altered one in the rear. The company says the fish has the
same flavor, texture, color and odor as a regular salmon; however, the
debate continues over whether the fish is safe to eat.
• Genetically engineered Atlantic salmon has an added growth hormone from
a Chinook salmon that allows the fish to produce growth hormone yearround. Scientists were able to keep the hormone active by using a gene
from an eel-like fish called an ocean pout, which acts as an “on switch” for
the hormone.
If the FDA approves the sale of the
salmon, it will be the first time the
government has allowed modified
animals to be marketed for human
consumption. According to federal
guidelines, the fish would not have to
be labeled as genetically modified.
Fast-dying salmon???
• GM salmon was created to increase the size of the fish more
quickly, however, studies were conducted that showed that GM
salmon are much less successful at producing viable offspring.
• Non-random mating habits of the wild salmon (they are more
attracted to the larger GM salmon) would imply a die-off of the
wild type genotypes leading to mass extinction of salmon
populations.
Computer simulations
have predicted die-outs
to occur in as little as 2
years after release into
the wild. This would
have a very serious
impact on ecosystems
all over the planet.
Will We Be Able To Cure Cancer
With Gene Therapy?
Cancer happens when body cells grow out of
control. Scientists have found a gene called p-53
which normally keeps cells under control. They
think that in some people with cancer, the disease
begins because the p-53 gene doesn’t work
properly – perhaps because of a mistake in the
gene code. Experts are now looking for a way to
cure cancer by modifying faulty DNA to make the
p-53 gene work.
Lung cancer cells
(530x). These cells are
from a tumor located in
the alveolus (air sac) of
a lung.
Going Bananas?
http://gslc.gen
etics.utah.edu/
features/gmfo
ods/
According to recent reports, the world may
soon be out of bananas. Because of the
starchy fruit’s unique method of
reproduction, it seems, banana plantations
in Africa, Asia and Central America are
uniquely susceptible to fungi, viruses and
pests. Unless scientists can find a way to
genetically enhance the banana’s ability to
ward off parasites, we could be bananaless
in ten years.
Several agroscience companies believe they
can genetically engineer such an invincible
banana by copying parts of the genetic
codes of other fruits and instilling them into
the banana.
Glow-in-the-dark cats
• In 2007, South Korean scientists
altered a cat’s DNA to make it glow in
the dark and then took that DNA and
cloned other cats from it — creating a
set of fluffy, fluorescent felines. Here’s
how they did it: The researchers took
skin cells from Turkish Angora female
cats and used a virus to insert genetic
instructions for making red fluorescent
protein. Then they put the gene-altered
nuclei into the eggs for cloning, and
the cloned embryos were implanted
back into the donor cats — making the
cats the surrogate mothers for their
own clones.
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.
Enviropig
• The Enviropig, or “Frankenswine,” as
critics call it, is a pig that’s been
genetically altered to better digest and
process phosphorus. Pig manure is
high in phytate, a form of phosphorus,
so when farmers use the manure as
fertilizer, the chemical enters the
watershed and causes algae blooms
that deplete oxygen in the water and
kill marine life.
• So scientists added an E. Coli bacteria
and mouse DNA to a pig embryo. This
modification decreases a pig’s
phosphorous output by as much as 70
percent — making the pig more
environmentally friendly.
Pollution-fighting plants
• Scientists at the University of
Washington are engineering poplar
trees that can clean up contamination
sites by absorbing groundwater
pollutants through their roots. The
plants then break the pollutants down
into harmless byproducts that are
incorporated into their roots, stems and
leaves or released into the air.
• In laboratory tests, the transgenic
plants are able to remove as much as
91 percent of trichloroethylene — the
most common groundwater
contaminant at U.S. Superfund sites —
out of a liquid solution. Regular poplar
plants removed just 3 percent of the
contaminant.
Medicinal eggs
• British scientists have created a breed
of genetically modified hens that
produce cancer-fighting medicines in
their eggs. The animals have had
human genes 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.
Another way to
manipulate genotypes
and phenotypes of
organisms is how we
breed them…
SELECTIVE BREEDING
• Selecting and breeding only
organisms with a desired trait in
order to produce the next
generation.
• Almost all domesticated animals
and most crop plants are the result
of selective breeding.
SELECTIVE BREEDING
• Once the breeder successfully
produced offspring with the desired
characteristic…usually inbreeding
occurs.
• Remember…recessive gene
defects will show up more
frequently after several generations
of inbreeding!
HYBRIDIZATION
• Another form of selective
breeding
• Choosing and breeding
organisms that show strong
expression for two different traits
in order to produce offspring that
express BOTH traits.
HYBRIDIZATION
• Labradoodle
(Labrador
Retriever +
Poodle)
• Puggle (Beagle +
Pug)
• Cockapoo
(Cocker Spaniel
+ Poodle)
HYBRIDIZATION
HORSE + DONKEY = MULE
HYBRIDIZATION
Female lion
with a male
tiger…TIGON
Male lion with
a female
tiger…LIGER
Recognize this bird?