Clones and Cloning
- By Dr. Andreas Lambrianides
- General Surgeon, Brisbane, Australia
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- Clones are genetically identical individuals produced from a single parent. Cloning is
not new. It has been used in plant breeding for years, and plant micropropagation
techniques are now highly sophisticated. Clones can be produced from both embryonic and
non-embryonic cells using nuclear transfer techniques. There are two distinct types of
cloning: therapeutic and reproductive. The former uses genetic material from the patient's
own cells to generate tissues to treat medical conditions, while the latter implants a
cloned embryo into a woman's uterus leading to the birth of a cloned baby. Proponents of
reproductive cloning often use the term therapeutic cloning, as they claim to treat the
disorder of infertility. Cloning in theory appears simple, however success depends on many
factors some of which scientists as yet do not understand.
The basic nuclear transfer technique, involves a fine needle that is used to withdraw
genetic material from a mature egg. They then introduce the nucleus of the donor cell into
the enucleated cell, which is exposed to chemicals and growth factors, in order to
activate division and growth. By the fifth day, a ball of cells, called the blastocyst, is
formed. It contains a group of cells called the inner cell mass that contains the stem
cells. The blastocyst is subsequently broken to obtain the inner cell mass that is grown
in tissue culture to produce stem cells. These cells are of great interest because of
their unique ability to develop into virtually any other human cell. It would be possible
to grow specific cells such as bone cells, liver cells, muscle or blood cells and thus
cure medical disorders such as diabetes, Parkinson's and other conditions, by replacing
faulty or diseased cells with healthy ones. Although stem cells can also be obtained from
an adult and other non-embryonic tissues they do not have the same capacity to transform
themselves the way embryonic cells do.
Blastocysts contain the inner cell mass with the stem cells. Subsequent break of the
blastocyst and growth of the inner cell mass to yield stem cells, that in turn can be
coaxed to grow into a variety of cells which can be injected into patients, has not yet
been accomplished in humans.
Embryos were successfully cloned from sheep in 1986, followed in 1998 by the birth of
Dolly, the first cloned lamb. Mammary cells were taken from the udder of a sheep and grown
in culture. An egg cell was taken from another sheep and its nucleus removed. The mammary
cell was then fused with the enucleated cell, and after a growing period of six days the
embryo was implanted in the uterus of a third sheep, similar to the egg donor. The result
after gestation was a lamb, Dolly, identical in appearance and chromosome make up to the
sheep that donated the mammary cell. Dolly's Genome however, cannot be completely
identical to the mammary cell donor, as Dolly's mitochondrial DNA is derived from the egg
cell donor. In July 1988, mice were cloned using nuclei from ovary cells.
In 2001, the completion of the first draft of human genome project was announced and the
United Kingdom parliament passed a regulation to allow the cloning of human embryos up to
fourteen days old for the purposes of research into serious diseases. Finally in October
in 2001, research workers managed to coax one human embryo to progress to a six-cell stage
at which point it stopped dividing. In a similar experiment the same group succeeded in
prompting human egg cells to develop into blastocyst but none clearly contained the inner
cell mass that yields the stem cells. By about one week after fertilization, cleavage,
which is a succession of rapid cell divisions, transforms the zygote, a single cell, into
a ball of much smaller cells called blastomeres, forming the embryonic stage called
blastocyst. At this stage the embryo has over a hundred cells arranged around a central
cavity. Protruding into one end of the blastocyst cavity is a cluster of cells called the
inner cell mass, which will subsequently develop into the embryo proper.
Some of the most ambitious medical projects involve the production of universal human
donor cells. Scientists know how to isolate undifferentiated stem cells in mice, and they
are also learning how to differentiate stem cells. All cells contain within their DNA the
information to reproduce an entire organism. In adult organisms, the cells' personal
access to parts of that information has been switched off as the cells specialize.
Scientists do not know as yet how to switch those genes back on again.
Such techniques may make it possible to manufacture cells to repair or replace tissue
damaged by illness such as diabetes, Parkinson's and muscular dystrophy. Stem Cells
matched to an individual could be made by transferring the nucleus of one of the patient's
cells into a human egg to create an embryo. The embryo will be allowed to develop to a
certain stage and then separate and culture stem cells from it.
Advocates of reproductive cloning aim to implant a cloned embryo into a woman's uterus
leading to the birth of a cloned baby. Therapeutic cloning on the other hand, seeks to use
genetic material from the patients own cells in order to generate healthy tissue cells for
repairing damaged organs, such as the occasion of generating healthy pancreatic tissue to
treat diabetes or nerve cells to repair damage nerve tracts. What is disturbing is that
advocates of reproductive cloning, use the term therapeutic cloning claiming that
infertility is a disease, and as such, cloning is justified as a treatment for
infertility. This supposition is totally unjustifiable.
Cloning whether reproductive or therapeutic in nature, is, and always will be, ethically
and morally wrong. Consider the significant incidence of death and birth defects in cloned
animals. When Dolly was cloned only one embryo in over two hundred was normal and many
showed gross abnormalities. To clone a human being, is to carry out a life long
experiment, which may result in adverse physical and psychological effects on the
individual, and any defects will be passed onto their offspring. Dolly was found to be
ageing prematurely and to suffer with severe arthritis in her left hind leg only two years
after its birth. Premature aging can be explained on the basis of the donor cells being
old and containing DNA material with short telomeres. Researches at the Monash institute
have shown, following research with mice and sheep, that the technique of reproductive
cloning, puts children at risk of being born with life threatening deformities, and the
mothers' life at risk due to major abnormalities of the placenta. These abnormalities
occur, because the cells used to clone the embryo will be taken from one of the potential
parents. These adult stem cells retain the memory of whether they were a muscle or skin,
which means, they do not grow and behave in the way stem cells in a placenta usually do.
Every born child is an original, and as such, deserves to be born his own individual
person. What is there to stop societies dictating which parent is chosen as the clone
donor? Are we to have pools of supermodels? Tall, green eyed, thin and everything else
that goes with them? Are we to replicate selected genomes on a large scale for military
purposes? Groups such as religious cults or renegade scientists have already announced
their intention to clone a human being. Is it ethically right to use human eggs for
research? In order to increase the yields of the eggs drugs have to be given to the donor
females and in rare cases these drugs can lead to liver damage, kidney failure or
cerebrovascular incidents. Some studies have also suggested the possibility of ovarian
cancer as a result of using these drugs. Finally one has to consider the risk of morbidity
and mortality during surgery to retrieve the eggs. Consider the commercial implications if
payments are made to females in order to entice them to become donors. Are human eggs
going to become a commercialized commodity? We do not permit the sale of human organs for
transplantation, yet sales occur on a regular basis. You can now buy a human kidney for
15000 U.S. dollars.
Have we considered the psychological implications on cloned individuals or even donors?
What would be the relationship between a cell donor and his clone? How do we deal with a
clone wanting to identify his or hers, "parent" donor? Cloned individuals may
face unrealistic expectations to live up to the standard of their cell donors and this
will create undue psychological problems.
Cloning, be it therapeutic or reproductive in nature is unacceptable. Human life begins at
conception and "activated" cells are morally equivalent to human embryos since
implantation of a cloned egg in the uterus, as carried out with animals, can go to full
development and birth. This requires the same degree of protection and respect. How can we
justify killing a living embryo to harvest its tissues for the benefits of others? Making
a human being in order to destroy it, is murder, and it should be treated as such.
Although the clone did not result from the fertilization of an egg by a sperm, yet the
result is the same. A living human being should not be regarded as a new biological entity
exempt from the moral law of God, and therefore ours to do as we please, to make and
destroy for our own gratification. We talk of cloning technology as being of benefit to
man kind and forget that there is always the desire to patent new technologies and make
money.
We love forming ethic committees to decide whether it is right or wrong in our own puny
morality to carry out cloning. Our feeble moral standards are not the ones that matter.
The all important question is whether cloning complies with the morality that counts, the
morality of our creator and God.
"Walk in the light of your fire, and the sparks that you have kindled. You have
chosen to deceive yourself; I will not undeceive you. You have kindled a false fire; I
will not extinguish it that I may give you a true one. No. Walk in the light of your fire
enjoy your false confidence, rest securely on your delusive hopes, foster your presumption
faiths, comfort yourself with your rites, forms, ceremonies and be fully persuaded of the
truth of your false doctrine. Go on to fill up the measure of your inequities to call
evil, good, and good evil. To put bitter for sweet and sweet for bitter until you have
neither eye to see the one not taste to discern the other."
On July the 31st 2001, the house of representatives voted on a broad ban on human cloning
that would not only prohibit the use of cloning for reproduction but would also prohibit
cloning for research purposes such as the derivation of stem cells that could be used
therapeutically. An amendment that would have allowed therapeutic cloning failed. The
issue of cloning is to be discussed further by the Senate.
- Let us not forget that an embryo is human life with the capacity to develop into a
natural human being. All of us that strongly believe that life begins once the egg cell
divides, also believe that we will be making and destroying human beings. We all have
sympathy with the suffering of patients but morally we can not agree with the doctrine of
making human embryos only to destroy them in order to treat a medical condition. We can
neither say that embryos do not have consciousness, as then we will embark on a collision
course to devalue the mentally disabled.
"There are many devices in a mans heart. Nevertheless the council of the Lord will
stand."
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