Transcript Embryonic Stem Cells & Cloning

NOTES –
Embryonic
Stem Cells
and Cloning
What are stem cells?
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Embryonic Stem Cells – cells present in
the early stages of an embryo’s
development that have the ability to
change in any type of body cell
What are the goals of stem cell research?
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Stem cell research is about repairing
and/or replacing damaged body tissues in
order to reverse some effects of aging,
disease, and injury
In the lab, scientists have seen embryonic
stem cells change into the cells of virtually
every part of the human body
Scientists want the ability to control the
development of these cells so they can
make the types of tissue they need, like
brain, heart, nerve, or muscle
Stem Cells in the Lab
The Potential of Stem Cells
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Stem cells can be used to generate cells and tissues that
could be used for cell-based therapies
Cell-based therapies —Treatment in which stem cells
are changed into the specific cell type required to repair
damaged or destroyed cells or tissues
Donated organs and tissues are often used to replace
damaged or destroyed tissue, but the need for
transplantable tissues and organs far outweighs the
available supply
Stem cells changed into specific cell types, offer the
possibility of a renewable source of replacement cells
and tissues to treat many diseases (Parkinson's and
Alzheimer's diseases, spinal cord injury, stroke, burns,
heart disease, diabetes, osteoarthritis, and rheumatoid
arthritis)
The Potential of
Stem Cells
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It may become possible
to generate healthy heart
muscle cells in the
laboratory and then
transplant those cells into
patients with chronic
heart disease.
Research in mice and
other animals indicates
that stem cells
transplanted into a
damaged heart can
generate heart muscle
cells and successfully
repopulate the heart
tissue
Mouse
The Potential of
Stem Cells
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In people who suffer
from type I diabetes, the
cells of the pancreas that
normally produce insulin
are destroyed by the
patient's own immune
system
New studies indicate that
it may be possible to
change human embryonic
stem cells to insulinproducing cells that
eventually could be used
in transplantation therapy
for diabetics
Where do embryonic stem cells come from?
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Embryonic stem cells must be taken from
the earliest stage of the embryo, called
the blastocyst
5 to 7 days after fertilization, the
blastocyst is ball of about 100 stem cells
There are two ways to produce blastocysts
from which stem cells can be taken:
fertilization of egg with sperm or cloning
Where do embryonic stem cells
come from?
Where do embryonic stem cells
come from?
Where do embryonic stem cells
come from?
Where do embryonic stem cells
come from?
Where do embryonic stem cells
come from?
Where do embryonic stem cells
come from?
Blastocyst
What is
cloning?
What is cloning?
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Cloning – making a genetic copy of an
existing organism
There are 2 types of cloning:
 Reproductive Cloning – cloning in
order to produce a genetic copy of an
existing organism
 Therapeutic Cloning – cloning in
order to produce a blastocyst from
which stem cells can be taken and
used to develop therapies for injury
and disease
How does reproductive cloning
work?
How does reproductive cloning
work?
How does reproductive cloning
work?
How does reproductive cloning
work?
How does reproductive cloning
work?
How does reproductive cloning
work?
How does reproductive cloning
work?
How does reproductive cloning
work?
Reproductive Cloning
How does therapeutic cloning work?
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Therapeutic cloning begins the same way
as reproductive cloning
Instead of implanting the blastocyst into a
surrogate mother, the stem cells are taken
out of the blastocyst and used to develop
whatever type of cells are needed
Cloned Embryo Stem Cells
What’s all the fuss about?
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When embryonic stem cells are removed from
the blastocyst, the embryo is destroyed
Is this the same as abortion? What rights does
the blastocyst deserve?
In 2001, President George Bush placed a ban on
federal funding for embryonic stem cell research
Researchers Cheer Obama's
Vote for Stem-Cell Science
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President Barack Obama signs an Executive Order
reversing the government's ban on funding stem-cell
research, during a ceremony in the East Room of the
White House on March 9, 2009