Abstract from: Cloning : Where Do We Draw the Line?
The first attempt in cloning was conducted in 1952 on a group of frogs.
The experiment was a partial success. The frog cells were cloned into
other living frogs however, only one in every thousand developed
normally , all of which were sterile. The rest of the frogs that
survived grew to abnormally large sizes. In 1993, scientist and director
of the in vitro lab at George Washington University, Jerry Hall and
associate Robert Stillman, reported the first ever successful cloning of
human embryos. It was the discovery of in-vitro fertilization in the
1940’s that began the pursuit to ease the suffering of infertile
couples. After years of research, scientists learned that "in a typical
in-vitro procedure, doctors will insert three to five embryos in hopes
that, at most, one or two will implant" (Elmer-Dewitt 38). And that "a
woman with only one embryo has about a 10% to 20% chance of getting
pregnant through in-vitro fertilization. If that embryo could be cloned
and turned into three or four, the cha
nces of a successful pregnancy would increase significantly"(Elmer-Dewitt
38).
The experiment the scientists performed is the equivalent of a mother
producing twins. The process has been practiced and almost perfected in
livestock for the past ten years, and some scientists believe that it
seems only logical that it would be the next step in in-vitro
fertilization. The procedure was remarkably simple. Hall and Stillman
"selected embryos that were abnormal because they came from eggs that
had been fertilized by more than one sperm" (Elmer-Dewitt 38), because
the embryos were defective, it would have been impossible for the
scientist to actually clone another person. They did however, split the
embryos into separate cells, as a result creating separate and identical
clones. They began experimenting on seventeen of the defective embryos
and "when one of those single-celled embryos divided into two cell…the
scientists quickly separated the cells, creating two different embryos
with the same genetic information" (Elmer-Dewitt 38). The cells are
coated with a protective covering "called a zona pellucida, that is essential to development" (Elmer-Dewitt
38), which was stripped away and replaced with a gel-like substance made
from seaweed that Hall had been experimenting with. The scientists were
able to produce forty-eight clones, all of which died within six days.
Other scientist have been quoted saying that although the experiment is
fairly uncomplicated, it had not been tested before because of the moral
and ethical issues surrounding an experiment such as this one. Some
people believe that aiding infertile couples is the only true benefit to
cloning human embryos, and fear that if the research is continued it
could get out of hand.
Other advantages that have been suggested include
freezing human embryos for later use, in the event that a child should
get sick or die. If a parent has had their child’s embryos cloned and
frozen and their child dies at an early age of crib death, the parents
could have one of the frozen embryos de-thawed and implanted into the
womb. Nine months later, the mother would give birth to a child that was identical to the
one they had lost. Or if a four year old child develops leukemia and
requires a bone marrow transplant. A couple could implant a pre-frozen
embryos clone of their first child and produce an identical twin as a
guarantee for a perfect match. The parents would therefore have
identical twins that were four years apart. The disadvantages are
endless. If this type of technique were exploited and used in vain, we
could be heading down "a tunnel of madness"(Elmer-Dewitt 37).
"Researchers have developed DNA- analysis techniques to screen embryos
for…disorders, but the procedures require snipping cells off embryos, a
process that sometimes kills them"( Elmer-Dewitt 39). It is expected
that the idea of throwing away an embryos because it is disease ridden
will throw pro-life activists into a frenzy (Elmer-Dewitt 39). It is one
thing to exercise the freedom of chose to abort an unwanted child for
whatever reason, but to throw one away due to a
pre understanding that it carries a disease, in my opinion, is
unethical. These types of possibilities are producing moral and ethical
debates among ethicists the world over. Most countries have set
regulations concerning cloning human embryos and in some countries it is
an offense punishable by law and requires incarceration . Between the
medical contributions and the ethical questions surrounding cloning
human embryos, it is unlikely that we will have the opportunity to
discover if further research to Hall and Stillman’s experiment could
actually produce human beings.
References
Elmer-Dewitt, Philip. "Cloning: Where Do We Draw the Line?" Time
Magazine. November 8th, 1993: 37-42.
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