Biotechnology
Cloning Genetically modified food
Four hot topics in biotechnology:
Stem Cells DNA Fingerprinting
Biotechnology: the engineering of organisms for useful purposes.
A chimera, a mixture of a goat and a sheep.
Biotechnology
Animal Cloning
Megan and Morag, the world’s first cloned mountain sheep.
Why Clone Animals?
1. To answer questions of basic biology
2. For herd improvement
4. To make us happy (e.g. pet cloning)
3. For pharmaceutical production
Prometea, the first cloned horse (in foreground) with her identical twin and
surrogate mother Stella Cometa.
Utah State University
(And Idaho State)First Cloned Mule
Egg Cell
Udder Cells
1. An egg is taken from the surrogate mother
2. A needle removes the DNA from the egg cell.
3. An udder cell (or other somatic cell) is taken from the organism being cloned.
4. The “blank” egg cell is fused with the udder cell.
5. Electricity stimulates the fused cell to begin dividing into an embryo.
http://www.jpvpk.gov.my/html/news/archives/English/Feb02%2016B.htm
The First Cloned Pet
Carbon Copy is not a phenotypic carbon copy of the animal
she was cloned from.
(Science (2002) 295:1443)
This is “Carbon Copy”…the first
cloned pet.
Rainbow and her clone “cc”
http://drsophiayin.com/blog/entry/cloning-cats-rainbow-and-cc-prove-that-cloning-wont-resurrect-your-pet
The First Cloned PetIf they are clones, why
aren’t the identical?
The genes that controls coat color can be active or inactive in each skin cell. This is a random process. Even though CC has the gene for orange spots,
that gene has been “turned off”
Read more about these un-identical clones here.
Is Animal Cloning Ethical?
The first cloned horse and her surrogate mother/genetic twin.
The answer can’t be determined by scientists alone.
Stem CellsA stem cell is a cell that has not yet been assigned a
specific function.During development the stem cells become specialized
Stem Cell
Nerve Cell
White Blood Cell
Skin Cell
Stem CellsThis specialization is terminal.
That means that once a cell has been specialized it can only produce more cells like it.
White Blood Cell White Blood Cell
One of the best sources for stem cells is an embryo of a developing fetus.
Stem CellsWhere can you find stem cells?
This is a four day old embryo called a blastocyst. Each of these developing
cells is a stem cell!
FYI: When stem cells are harvested, the embryo is destroyed and can no longer grow into a fetus
Stem CellsWhat do scientists do with stem cells?
Researchers believe that stem cells can be used to replace damaged tissue caused by:
CancerMultiple Sclerosis
Parkinson’s DiseaseSpinal Damage
Ethical Questions
If stem cells are taken from these masses, are you destroying
life?
Are these masses of cells a human?
More Ethical DilemmasAt what point does an embryo become a
human?
Is it ethical to use “extra” or “left over” embryos from In Vitro fertilization for stem
cell research?
If your grandfather developed a disease that could possibly be cured using stem cells, would you donate an embryo?
Stem CellsThere ARE other sources for stem cells, but they
are believed to be inferior to embryonic stem cells:
Bone Marrow
Lipid cells
DNA Fingerprinting
A DNA fingerprint used in a murder case.
What are we looking at?
The defendant stated that the blood on his clothing was his,
was he telling the truth?
DNA Fingerprinting
Different individuals carry different alleles.
Most alleles useful for DNA fingerprinting differ on the basis of the number of repetitive DNA sequences they
contain.
DNA FingerprintingDNA can be cut up in pieces
of alleles. Each piece is a different size.
A DNA fingerprint is made by analyzing the sizes of DNA
fragment.
The DNA Fragments Are Separated on the Basis of Size
The technique is gel electrophoresis.
The pattern of DNA bands is compared between each sample loaded on the gel.
DNA Electrophoresis Animation
Genetically Modified Foods
We genetically modify our food for disease resistance, to change its taste, and to make it
grow faster and larger.
Genetically Modified Foods
What is the controversy?
A branch of government called the “Food and Drug Administration” (FDA) is responsible for determining if a food or drug is “safe”
For example, genetically modified salmon:The FDA treats this as an animal drug and
not a food. This means they have a very narrow definition of “safe” and do not
necessarily run the correct tests on the salmon before we eat it.
http://www.sciencemag.org/content/330/6007/1052.full.pdf
Genetically Modified FoodsHowever, many organizations have used what we DON’T KNOW about
GM foods to try to stop genetic engineering of foods all together.
The “Indian Institute of Science” noted that people have been eating GM corn
for more than a decade in several countries, and there have been no
related health issues reported.http://www.nature.com/nature/journal/v480/n7377/pdf/480321d.pdf
Methods for Plant Genetic Engineering are Well-Developed and Similar to Those for
Animals
Golden Rice is Modified to Provide a Dietary Source of Vitamin A
Worldwide, 7% of children suffer vitamin A deficiency, many of them living in regions in which rice is a staple of the diet.
However, many of these same regions have banned GM foods
Golden rice (yellow) with standard rice (white).
Here in the U.S. more GM crops are grown each year:
Genetically Modified Crops
Genetically Modified Cotton (contains a bacterial gene for
pest resistance)
Standard Cotton
BiotechnologyLet’s summarize:Four of the most talked about biotechnology
efforts are in cloning, stem cell research, DNA fingerprinting, and genetically modified foods.
Advances in biotechnology raise ethical questions that scientists alone cannot answer.