Transcript Transgenics - MsSunderlandsBiologyClasses

Transgenics
Ashten Gulizo
Samantha Baldassaro
What is it?
• An organism that carries a gene that
has been deliberately inserted into its
genome1
• Usually causes a trait that is novel and
uncharacteristic of the organism1
How do you do that?
1. Transform the embryonic stem cells
growing in tissue culture with the desired
DNA (transgenic gene)1
2. Inject the desired gene into the pronucleus
of a fertilized egg1
•
The haploid nucleus of a sperm or egg cell
before fusion of the nuclei in fertilization2
1
Examples
•
•
•
•
Mice
Chicken
Primates
Pigs1
•
•
•
•
Genetically Modified crops3
Sheep
Goats
Fishies1
Applications
• May 28, 2009
– Japanese scientists report success in creating
transgenic marmosets (a primate). Closest
human relative to be genetically engineered. In
some cases, the transgene (for green fluorescent
protein) was incorporated into the germline and
passed on to the animal's offspring.1
– These transgenic animals will provide the best
model yet for studying human disease and
possible therapies.1
The monkeys glow in
the dark!
• July 2000
Applications
– Success at inserting a transgene into a specific
gene locus was reported in goats and sheep. The
gene was the human gene for alpha1-antitrypsin,
and two of the animals expressed large
quantities of the human protein in their milk.1
– rheumatoid arthritis, cancer, and other
autoimmune disorders (other proteins) 4
Bahhhh!
I’m a sheep!
Applications
• Transgenic pigs & mice have also been
produced by fertilizing normal eggs with
sperm cells that have incorporated foreign
DNA. This procedure, called spermmediated gene transfer (SMGT) may
someday be able to produce transgenic pigs
that can serve as a source of transplanted
organs for humans. 1
Applications
• Scientists have developed sunflowers that
are resistant to mildew. 4
• They have also developed cotton that resists
insect damage.4
Applications
• Goats with spider genes produced spider
silk proteins in their milk, after the genes
were inserted into the genome of a goat’s
egg, prior to fertilization.
– strong, lightweight bulletproof vests
– stronger automotive and aerospace
components
– stronger, more biodegradable sutures for
closing wounds.4
Pretty Much…
• The use of
transgenics in other
organisms can lead
to the synthesis of
human organs and
proteins, bettering
crops for our use,
and many other
areas.
papaya
bullet proof vest
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Ethical Concerns
Are we blurring the lines between species by creating transgenic combinations?
What are the known health risks associated with transgenics?
What are the long-term effects on the environment when transgenics are released in the field?
What ethical, social, and legal controls or reviews should be placed on such research?
Are we inflicting pain and suffering on sentient creatures when we create certain types of
chimeras?
Will transgenic interventions in humans create physical or behavioral traits that may or may
not be readily distinguished from what is usually perceived to be “human”?
If the blending of nonhuman animal and human DNA results, intentionally or not, in chimeric
entities possessing degrees of intelligence or sentience never before seen in nonhuman
animals, should these entities be given rights and special protections?
What unintended personal, social, and cultural consequences could result?
Will these interventions redefine what it means to be “normal”?
Who will have access to these technologies, and how will scarce resources be allocated?
Are we crossing species boundaries?
Will the technology facilitate transmission of disease?
Is it ethical to create altered animals that may suffer?
Is it possible the technology may be used to create slaves?
Can the definition of “human” be applied to altered species containing human genes?
Will society manipulate the genetic traits of children? 4
Ethical Concerns
•
•
•
•
Health Concerns
Environmental Concerns
Transmission of Disease
Animal Cruelty
Regular
• Crossing Species Boundaries
• Chimeric – Sentient – “Human” 4
CANADA
• The regulation of all transgenics in Canada falls
under the mandate of the CFIA and Health Canada.
• Responsible for release of transgenics into the
environment, and requires each transgenic to
undergo stringent safety assessments before release.
– These include human food, livestock feed, and
environmental safety.
• Submit data collected under regulatory guidelines,
and data must show that the mandatory tests have
been completed. The agencies review the data, and
if acceptable, confined field testing will be allowed.5
SWITZERLAND
• Switzerland has a tight rein on crop genetics,
because they fear that a mutant strain might
run amok and harm the environment.
• Their laws in this area are more restraining
than American laws.
• 1990s - the Swiss constitution was amended
in order to defend the dignity of all creatures,
including plants & “social animals”, against
unwanted consequences of genetic
manipulation.6
PERU
• As of now, transgenic crops of all kind are
illegal in Peru.
• However, soybeans imported from Brazil
and Argentina as animal feed have been
planted illegally.
• Worried, like many other countries about
contamination of native species of crops.7
References
1.
2.
3.
4.
5.
6.
7.
http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/T/Transgenic
Animals.html
http://www.answers.com/topic/pronucleus
http://www.cls.casa.colostate.edu/TransgenicCrops/what.html
http://www.actionbioscience.org/biotech/glenn.html
http://crop.scijournals.org/cgi/content/full/43/5/1590
http://online.wsj.com/article/SB122359549477921201.html
http://www.livinginperu.com/features-710-environment-transgenicproducts-are-not-our-first-choice