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Cloning Essay Research Paper Cloning the process

Cloning Essay, Research Paper Cloning, the process of ?Manipulating a cell from an animal so that it grows into an exact duplicate of that animal is the forbidden fruit of biology.?

Cloning Essay, Research Paper

Cloning, the process of ?Manipulating a cell from an animal so that it

grows into an exact duplicate of that animal is the forbidden fruit of biology.?

(Begley 54). The word ?clone?, derived from the Greek word ?Klon?,

meaning twig or slip, refers to asexual reproduction. Also known as vegetative

reproduction. Cloning became known to the public about 30 years ago. This idea

of cloning about his time resulted in an experiment of the successful asexual

reproduction. This experiment took place in England, where a whole bunch of

tadpoles was cloned by the technique of nuclear transplantation. Nuclear

transplantation refers to the process of moving a nucleus from one cell to

another. (Mckinnel 28) The person responsible for this introduction of cloning

was Joshua Lederberg, a noble laureate geneticist. (Kass, Winters 9)

Scientists have known for a long time what it took to clone, and many had

found themselves believing that it was biologically impossible. One problem was

the way the embryo develops. Every cell in the body comes from the same

fertilized egg therefore, every cell in the body contains the same genes. But

animal and human cells are specialized and different, so that a heart cell acts

as a heart cell and a liver cell acts as a liver cell. This specialization

starts when the fetus is formed, and once a cell reaches its final state, it

never changes. A brain cell will always be a brain cell as long as a person is

living, it would never change into a liver cell although it contains the same

genes. (Kolata 24)

Frogs were the first multicellular animals to be cloned in the 1950?s. A

thorough cloning experiment produces a frog asexually. No gamete nucleus, sperm

or egg, participates in the development of a frog that is truly a clone. (Mckinnel

3) The cloning procedure in frogs, toads, and salamanders is very difficult. In

order to start this cloning process, the ability to obtain eggs and sperm from

frogs had to be introduced. Also the process of vitro fertilization, removal of

maternal chromosomes from eggs, and the splitting of embryos into individual

cells. (140) To obtain frog eggs, the eggs have to grow to their maximum size

and the frogs are ready for hibernation under the ice of lakes and streams.

Ovulation can be induced from September to or past the time of natural

ovulation. Eggs leave the ovary, move to the reproductive tubes, and become

available to the embryologist when the female frog is injected with pituitary

glands or a combination of pituitary glands and the hormone progesterone. The

eggs can be removed from the female after this treatment by gently squeezing the

abdomen. (41)

Frog sperm can be obtained by cutting the testes of the frog into small

pieces in a diluted salt solution. The testes are dissected from the male, which

usually requires sacrifice of the frog donor. Then, a commercially available

hormone present in pregnant humans, is injected into a mature male frog. Within

one hour, millions of sperm are released from the testes of the frog and found

in the frog?s urine. This sperm is then capable of fertilizing frog eggs.

(41-42)

Eggs and sperm can be combined in a glass dish at a precise time. By caring

for the fertilized eggs at a particular temperature and time, donor embryos of

predetermined stages can be obtained. Using glass dishes is a simple and

efficient way of producing the frogs since frog eggs are very large and contain

an immense amount of stored food. (42)

The next step to the cloning of frogs is to prepare the frog eggs to receive

a transplanted nucleus. Freshly ovulated eggs have the same amount of DNA as an

ordinary body cell. That amount of DNA is twice the amount found in a sperm; so

it is called diploid. A sperm contains the haploid amount of DNA. The fact that

the ovulated eggs are diploid, helps with the experiment greatly. If diploid

eggs could combine with diploid sperm, than the amount of DNA in the offspring

would become enormous in only a few generations, but this does not happen. What

happens is that the frog egg becomes haploid as the sperm already is, after it

is released from the ovary and at that time it is activated by the penetration

of the sperm. This results in an egg devoid of any genetic material in the form

of chromosomes. This egg only has to be removed from the jelly envelope that

surrounds it by cutting it with scissors, in order for it to be ready to be

transplanted in to a nucleus. (42-43.)

After the jelly envelope is removed from the egg it is placed in a solution

that separates each individual cell of the egg. The surgery that is needed to be

performed involves using micropipettes, microinjection apparatus, and

micromanipulation equipment. This micropipette is a glass tube that is

positioned adjacent to the one cell selected from the many cells with the

microinjection apparatus. The donor cell is then drawn into the micropipette

with the microinjection apparatus, which is a machine that holds a tool very

steady, and allows small precise movements of that tool. When the cell enters

the opening of the micropipette, the cell membrane is ruptured and there is

slight leakage of its cytoplasm. The cell membrane is very thin but extremely

important. (43-46) If the membrane is left on the inserted donor cell, the ovum

with its donor cell cannot develop. However, a donor cell with its nucleus apart

from the membrane can come together with the egg cytoplasm to start the

developmental system-which sometimes results in the formation of a frog. (46.)

The process of cloning frogs took very long to do and was often very

unsuccessful. (Cohen 13)

Twenty years ago, when only the lowly tadpoles had been cloned, bioethicists

raised the possibility that scientists might someday advance the technology to

include human beings as well. (Woodward 60) In 1978, the infertility revolution

began. Louis Brown, who was born in England, was the world?s first test-tube

baby. Scientists had learned to fertilize women?s eggs outside their bodies,

allowing human life to start and take place in a petri dish in a laboratory. (Kolata

11)

In 1993, embryologists at George Washington University cloned human embryos,

they took cells from 17 human embryos, (defectives ones) they then teased apart

the cells, grew each one in a lab dish and got a few 32-cell embryos, a size

that could be implanted in a woman. (Begley 55)

One of the greatest cloning experiments ever accomplished was the production

of Dolly. Scientist Ian Wilmut used several techniques learned from his research

group and others to clone a sheep and make Dolly. Keith Campbell, his colleague,

sucked the nucleus out of an egg that was taken from an ewe. This created an egg

with the absence of genes that would die without its nucleus. So he began the

process of putting the nucleus of an udder cell in to the egg. (Kolata 21) He

slipped the udder cell underneath the outer membrane of the egg. Next, he hit

the egg for a few small seconds with bursts of electricity. This opened the

pores of the egg and the udder cell ? so that what was in the under cell,

including chromosomes would go into the egg and remain there. Now the egg had a

nucleus shared by the udder cell. The electricity made the egg act as if it were

fertilized. ( 27) After 21 times of repeating this experiment, Wilmut and his

colleagues had managed to create this frisky little lamb name Dolly. Dolly does

not resemble her biological mother, she is an exact copy or replica of her

mother?s identical twin. (Nash 62).

Dolly was born on July 5, 1996 at 5:00 p.m. she was the most famous lamb to

enter the world and a creation that would change the world forever. She was born

in a shed, just down the road from the Roslin Institute, in Scotland where she

was created. She weighed 6.6 kilograms, or 14.5 lbs. (Kolata 1-2)

Although the cloning of Dolly was a great success, it was a very frightening

task, but it soon became a question on everyone?s mind. (Kolata 10)

Roslin researchers struggled for 10 years to achieve their breakthrough.

Finally, political and religious leaders around the world grasped the concept

that if scientists can clone sheep, they can probably clone humans too. (Nash

62).

Many different concepts of cloning have been considered since it is such a

very controversial issue. Some views discuss why cloning would serve the world

with answers to the questions asked and possibilities thought of, while others

feel cloning is just a way of making the world even more confusing than it

already is.

The ability to clone adult mammals, in particular, opens up numerous exciting

possibilities; from propagating endangered animal species to producing

replacement organs for transplant patients. (Nash 63)

The government could put a restraint on the cloning of human beings and they

can also issue regulations that limit the work researchers can do. But the

government cannot stop people or groups of people that want to clone humans. Now

the cloning of humans is within reach and society as a whole is caught with its

ethical pants down. (Woodward 60) Muslim Scholar Aldulaziz Sachdina, a medical

ethicist at the university of Virginia, asks ?Imagine a world with no need for

marriage.? ( 61)

?The study of cloning can give the world deep insights into such puzzles as

spinal cords, heart muscle & brain tissue that won?t regenerate after

injury, or cancer that reverts to embryonic stage and multiplies ?Uncontrollably?.

(60)

?It?s a horrendous crime to make a Xerox of someone,? argues author and

science critic Jeremy Rifkin. ? You?re putting a human into a genetic

straitjacket. For the first time, we?ve taken the principle of industrial

design ? quality control predictability ? and applied then to a human being.?

(Kluger 20)

Father Richard McCormick, a veteran Jesuit Ethicist at the University of

Notre Dame, represents the hardest line. ?Any cloning of humans is morally

repugnant. A person who would want a clone of himself, says McCormick, is

overwhelmingly self-centered. One Richard McCormick is enough.? (Mckinnel 8)

The cloning of a human beings would be unethical because it would not serve

any necessary or beneficial medical purpose. The research needed to develop

human cloning would produce many imperfect results, and it would be sinful to

simply dispose of these ?mistakes?. In addition, if humans were successfully

cloned, such persons would have no parents and would therefore be less then

fully human in status. Furthermore, scientists simply do not have the wisdom to

direct the cause of evolution. (O’ Connor, Winters 9)

? Cloning is inherently despotic, ?Writes kass, for it seeks to make

children (or someone else?s children) after ones own image (or an image of

ones choosing) and their future according to ones will. In some cases, the

despotism may be mild and benevolent. In other cases, it will be mischievous and

downright tyrannical. But despotism ? the control of another through ones own

will it inevitably will be.? (Kass, Winters 10)

Protestant ethicist Vershey of Hope College in Holland, Michigan, warns that

cloning would program parents to ?think of their children as products.?

(Woodward 60)

Many people feel that cloning human beings is not a good idea. They measure

the morality of any act by the intention behind it. They are also concerned

primarily with the consequences ? for society as well as the individual. (60)

What we must understand is that cloning is not a second chance at life, but

another souls chance at your life. Of all the fears such as, a world with no

marriage, children being thought of as products, and all the questions such as,

does the original and clone share the same Karma, (Woodward 60) the ultimate

nightmare scenario would be the idea of a dictator being genetically duplicated.

While some of us are hoping for the next Einstein or Elvis, someone else may be

waiting for the next Hitler or Jeffrey Dohmer. (Kluger 71)

Although cloning of human beings may not be totally beneficial the cloning of

animals can serve as a benefit of many different purposes. With animals, you

could make the clotting factors used for Hemophilia. It may even be beneficial

for cystic fibrosis. (Wilmut, winters 50) Animals that are on the verge of being

instinct can be kept alive instead of being wiped off of the face of the earth.

(Kolata 10)

Many effects come along with the cloning of animals and humans. ?Here?s

the rule?, says psychologist Jerome Kagan of Harvard. ? You will never get

100% identity ? never ? because of chance factors and because environments

are never exactly the same.? (Begley 55)

A clone could resemble the individual it was made from, but there could be

many changes in the traits of that clone, which make up that individual, such as

personality, character, intelligence and talents. (55)

Embryologist Colin Stewart of the National Cancer Institute found an obstacle

in human cloning. He found that in sheep embryos, the genes from the donor cell

don?t turn until they have divided about 3 or 4 times, but in humans the genes

turn after 2 divisions. This may be the answer to the obstacles of cloning,

although it may not (55)

There are thousands of questions that come up with issue of cloning, like who

will be the surrogate mother, or who will provide a foster uterine environment

for the clone? We are more advanced in technology of ovulation and

micromanipulation of nuclei that we can produce an artificial placenta. So

cloning of humans will take place, which will rescue women from the burden of

pregnancy. (Mckinnel 111)

If we cloned humans, it would result in abnormal offspring and there is no

guarantee that a fetus will be completely undamaged. (110) Even if we do agree

on which individuals would serve as humanity?s templates of perfection, there?s

no guarantee that successive copies would be everything that the originals were.

(Kluger 71) ?As far as anyone can tell, Dolly is an exact copy of the ewe who?s

DNA she carries. But with sheep it?s kind of hard to spot differences anyway.

When it comes to people, genes are only the start.? (Begley 57)

Although Dolly may look like a young, healthy lamb, there are still many

things to consider, and many questions to be answered. The cell being cloned has

undergone years of mutation, and these mutations cannot be detected. It is

possible that Dolly may not live very long because she came from a six year old

cell. She may exhibit signs of premature aging. In addition, cloning sometimes

damages DNA, as a result, she may develop a number of diseases. (Nash 65)

Some possibilities of cloning makes us wonder, if cloning is misused it may

be possible that the results will be enormous. The possibility of ?Virgin

Births?, resurrecting the dead, and women giving birth to themselves,? ( 64)

is very scary and very real. While cloning may be a scientific breakthrough, and

open up a world of possibilities it is important to remember that human cloning

is very serious, and could contain many results that could disrupt the course of

ones life in many ways. If in the wrong hands cloning can be very dangerous. It

is much to involved to take lightly, and it may make an already chaotic world

destructive!

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