Should Humans be Cloned?

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 Cloning is creating a plant, animal, or
person asexually. They is genetically
identical with a donor plant, animal, or
person.
 There are two major types of cloning:
1. Reproductive cloning
 Therapeutic cloning
Dolly was created in a process called “Somatic
Cell Nuclear Transfer”
 Scientists transfer genetic material from a
donor adult cell to an egg whose nucleus has been
removed
 The reconstructed egg which contains the DNA
must be treated with chemicals in order to
stimulate cell division
Reproductive Cloning - Dolly
Then it is transferred to the uterus of a female
host where it develops until birth
Dolly is not an identical clone, only the clones
nuclear DNA is the same as the donor
Dolly’s success is truly remarkable because it is
proved that the genetic material from the
specialized adult cell can be re-programmed to
generate an entire new organism
Enucleation
The recipient oocyte is held by a glass pipette (left side of each frame), while a
glass needle is used to remove the genetic material in the process of enucleation.
Cell Transfer
A cell containing the genetic material from the donor is placed inside the Zona
Pellucida. An electrical pulse is then applied across the two cells, causing their
membranes to fuse into one complete cell.
 Also known as “embryo cloning,” it is the
production of a human embryo for the use in
research
 The goal of this is not to create cloned
humans, but to harvest stem cells that can be
used to study and treat disease.
Stems cells are important because they can
be used to generate any type of specialized cell
in the body.
Therapeutic Cloning
• Many researchers hope that one day stem
cells can be used to serve as replacement cells
to treat heart disease, cancer and other
disease.
• The Advanced Cell Technologies (ACT)
announced they cloned the first human
embryos. They collected eggs from women’s
ovaries, removed the genetic material and
inserted a skin cell inside the Enucleated egg
to serve as a new nucleus.
Reproductive cloning can be used to repopulate
endangered animals.
 Cloning extinct animals is a much greater
challenge to science because the egg and the
surrogate needed to create the cloned embryo
would be a species in its own.
Therapeutic cloning may be used to produced
whole organs from single cells.
 Scientists hope that one day therapeutic
cloning can be used to generate tissues and
organs for transplants.
 Stem cells would generate an organ or tissue
that is a genetic match to the recipient, as a result
organ donation would reduce significantly.
 Many challenges must be overcome before
cloned organ transplants can be created.
 More than 90% of cloning attempts fail to
produce viable offspring
 Cloned animals tend to have higher rates
of infection tumor growth, and other
disorders.
 Clones have been known to die
mysteriously.
Risks of Cloning
• A process called “Imprinting”,
chemically marks the DNA from the
mother and the father so that only one
copy of a gene is turned on.
• Any defect on the genetic imprint may
lead to some abnormalities of cloned
embryos
Because of the lack of understanding about
reproductive cloning scientists believe it is
unethical to attempt to clone humans.
 About 30% of clones born alive are affected
with “large offspring syndrome”
Should Humans be Cloned?
• Several cloned animals have died
prematurely from infections or other
complications, the same problems would
be expected in human cloning
• The attempt to clone humans at this time
is considered potentially dangerous, and
ethically irresponsible.
Producing a person through cloning lacks the
intimate connection to marriage.
 The nature of cloning is an affront to the
dignity and rights of a child.
 Artificial Insemination separates the link
between sexual intimacy and procreation.
Is Cloning or Stem Cell
research moral?
• The Catholic Church's objection is
to creating and using life for
research
• In either case, a human life is
created but deliberately prevented
from reaching its full potential.
John Paul II
• In his 1995 encyclical The Gospel of
Life, Pope John Paul II wrote:
"Human embryos obtained in vitro are
human beings and are subjects with
rights; their dignity and right to life
must be respected from the first
moment of their existence. It is
immoral to produce human embryos
destined to be exploited as disposable
'biological material'" (1,5).
• "While much good may come from the
proposed research, we must not lose
sight of the fact that the means used to
reach that good end must also be
moral. The end does not justify the
means. In this case, curing even
thousands of persons does not justify
the destruction of others, even though
they are still in the embryonic state of
development."
Time magazine – Feb 2004
Time magazine – Feb 2001
www.humancloning.org/
www.howstuffworks.com/cloning.htm
http://www.americancatholic.org/News/StemCell/ask_stemcell.asp
Ideas by Madeline Luciano
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