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Cloning Essay, Research Paper

The biological definition of a clone is an organism that has

the same genetic information as another organism or organisms

(”Cloning”, 1997). From this definition and from information

about the science behind cloning, my current view on cloning is

that it is ethical. This statement ignores information about how

we can misuse cloning and what consequences occur when the

procedure is unsuccessful. I currently do not think cloning

should be used until it is perfected. I doubt however that we

will allow cloning to be misused, and think most people would

probably have this opinion on cloning, but their lack of

knowledge on cloning, or their belief that cloning would be

misused, is the reason for differences of opinion. Thus, an

elaboration on the history, techniques, ethics, and reasons for

researching the technology of cloning is necessary.

The first thing that must be cleared up is what is cloning,

and what is a clone. A clone is an organism derived asexually

from a single individual by cuttings, bulbs, tubers, fission, or

parthenogenesis reproduction (”Cloning”, 1997). Parthenogenesis

reproduction is the development of an organism from an

unfertilized ovum, seed or spore (”Parthenogenesis”, 1997).

Hence, cloning, biologically speaking, is any process in which

production of a clone is successful. Thus, the biological term

cloning is the production of a genetically identical duplicate

of an organism. However, people can use the word cloning to

intend other meanings. For instance, we generalize many older

and new techniques as cloning. This is not a good practice

because these techniques are different and impose unique concerns

and issues.

In the world of scientific technology, cloning is the

artificial production of organisms with the same genetic

material. Scientists actually call the transferring of a nucleus

from the cell of one organism to an enucleated egg cell nuclear

transfer (Wilmut, 1997). This will produce an organism that has

the exact genetic material as that of the donor cell. Scientists

are using current techniques exceedingly more, and with a variety

of species. Astonishingly, more clones are present in the world

than one would think.

In nature, and even in the lives of humans, clones are

present. As stated earlier, a clone is an organism that has the

same genetic information as another organism. From this we can

say that cloning occurs with all plants, some insects, algae,

unicellular organisms that conduct mitosis or binary fissions,

and occasionally by all multicellular organisms, including

humans. Monozygotic twins, or identical twins, are clones of

each other. They have the same exact genetic information due to

the division of an embryo early in development which produces two

identical embryos. About eight million identical twins are alive

in the world, thus, already eight million human clones inhabit

the world. In unicellular organisms, a cell will produce two

daughter cells that have the same genetic material.

Today, the only cloning research is occurring in scientific

model organisms. These are organisms that research scientists

from around the globe have collected copious amounts of data.

All this data is necessary so that advancements in research can

continue more efficiently. The most common scientific models are

E. coli, mice, fruit flies, and frogs. The first organisms that

were cloned using nuclear transfer were frogs. This is because

they have large egg cells and scientists can obtain up to two

thousand of them from one ovulation. (McKinnel, 1979)

Successful cloning has occurred with livestock. The drive

toward success is not because livestock like cows and sheep are

model organisms. Instead, the farming industry has made and

continues to make a big effort toward finding a way to implement

the technique of nuclear transfer for livestock. Research in

cloning is also occurring in primates. The reason for studying

primates is the similarities with humans. This leads us to the

most talked about aspects of cloning, the use of the techniques

with human cells and eggs.

Throughout this century, conversation, novels, magazine

articles, newspaper reports, and movies have focused on the

implications of cloning humans. Part of this media creates

thoughts of a utopian society, while some a horrific world; the

majority of them being the latter.

For those who have had these frightening thoughts, Dr.

Richard Seed states he can accomplish the task of cloning a human

using nuclear transfer. Dr. Seed is a physicist who researched

fertility sciences in the 1980’s and is now specializing in

embryology. He states that he has set up a fertility clinic that

can conduct nuclear transfer. Dr. Richard Seed is creating an

uproar regarding the ethics of cloning. This is ironic because

cloning has occurred. (Flock, 1998)

Cloning of humans in a biological sense already has and is

occurring. Scientists are researching by splitting embryos to

execute experiments to find data relating to cell

differentiation, the use of stem cells, and genetic screening.

Amazingly, genetic screening is occurring in Britain quite often.

Fertility clinics aim this service toward couples where the

mother or father has a genetic disorder. A fertility clinic will

clone an embryo, then test it for genetic disorders. If the

embryo is tested negative for genetic disorders, then the

fertility clinic implants a clone of that embryo. This should

guarantee that the child will not have any genetic disorders.

(Benoit, 1996)

That is the current work with cloning. It is becoming a

part of our society already. Cloning is currently a technology

that many people could use. I believe it will become more

popular as prices for the technique decreases, and as the use of

cloning becomes increasingly acceptable. That is if we humans

consider cloning an acceptable technology, and that we would like

to use for the twenty-first century. Cloning has progressed so

quickly, few of us know if we should be even fooling with this

technology. Some scientists say that we put technologies to use

once the pros outweigh the cons. A good place for us to find

that information is to look at the past and current research

results with cloning and why scientists research it.

Amazingly, the first attempts at artificial cloning were as

early as the beginning of this century. Adolph Eduard Driesch

allowed the eggs of a sea urchin develop into the two-blastomere

stage. Then he separated it by shaking it in a flask and

allowing them to grow. The cells developed into dwarf sea

urchins. Driesch could not explain his experiments and gave up

embryology for philosophy (McKinnel, 1979).

The first implantation of a nucleus into an egg cell

occurred in 1952 by Robert Briggs and Thomas J. King in

Philadelphia. They had transferred the nuclei of Leopard Frogs’

eggs (McKinnel, 1979). The egg cells did not develop.

Successful cloning of embryo cells was accomplished later in the

1970’s by Dr. John Gurdon. The frogs did not develop beyond

tadpoles. In 1981, investigators announced they had transplanted

nuclei from mouse embryos into mouse eggs. However, other

scientists tried to duplicate the experiments, but found that

they fabricated the cloning results. (Kolata, 3 March 1997)

During the late seventies and early eighties, there were few

scientists still studying cloning. Many had predicted that it

was impossible to clone embryonic mammal cells. Few continued

with research. Many gave up and went into other fields.

However, some persisted and were rewarded for their efforts.

In 1984, Dr. Steene Willadsen announced that he had

successfully transferred nuclei from embryos of sheep to produce

clones (Kolata, 1997). He also was successful with cows and even

monkeys. He advanced his methods, and began cloning embryos that

were in the 64-128 cell-stage. This suggested that perhaps

nuclear transfer was possible with differentiated cells. More

exciting was when Dr. Neal First produced cows by nuclear

transfer from more developed embryos in 1994 (Kolata, 3 June

1997). Dr. First produced four calves. Two years later, Dr. Ian

Wilmut and Dr. Keith Campbell, of the Roslin Institute in

Edinburgh, Scotland, produced for the world Megan and Morag, the

first cloned sheep from embryo cells. Their new technique

involved the starving of the donor embryo. This would put the

cell in the right moment in the cell cycle, thus allowing the

genetic material to integrate more successfully with the egg

cell. This was the integral step of nuclear transfer. Dr. First

had executed the same step, but a laboratory staff member did it

accidentally, and First did not realize the significance of his

staff member’s blooper (Kolata, 3 March 1997). Dr. Wilmut and

Dr. Campbell became world famous. Their fame was not finished

yet however.

On July 5 at 4:00 P.M. lamb number 6LL3 (Campbell, 1997), or

Dolly, was born in a shed down the road from the Institute. She

weighed in at 14? pounds and was healthy. Scientists

accomplished this by using frozen mammary cells taken from a

six-year-old pregnant ewe and fusing them with an enucleated egg.

The trick to fusing the cells is giving a small electric current

to the petri dish on which the egg cell is. This stimulates the

egg much like a sperm would, and usually takes the genetic

material from the cell and becomes a zygote. They let this

zygote grow into an embryo, and then transplanted the embryo in a

recipient ewe, acting as a surrogate mother. This procedure

occurred late in January of 1996. This was the day of fusion date

for Dolly, which is the natural equivalent to a conception date.

An interesting note is that three different sheep were involved

in producing Dolly, versus the usual two or one (in-vitro

fertilization). Furthermore, the Roslin scientists used three

different breeds for each sheep to prove that the experiment was

a success. (Kolata, 3 March 1997)

After Dolly came other sheep, cows and even rhesus monkeys

cloned using similar techniques but with slight variations.

These cloned animals came from Roslin and many universities from

across America. They even produced clones which had genes that

would produce certain proteins. For instance, at Roslin,

scientists are trying to produce sheep that produce milk with

beneficial proteins for Cystic Fibrosis patients.(Kolata, 24

February 1997)

The goals and purposes for researching cloning range from

making copies of those that have deceased to better engineering

the offspring in humans and animals. Cloning could also directly

offer a means of curing diseases or a technique that could extend

means to acquiring new data for embryology and development of

organisms as a whole. Currently, the agricultural industry

demands nuclear transfer to produce better livestock. Cloning

could massively improve the agricultural industry as the

technique of nuclear transfer improves. Currently, change in the

phenotype of livestock is accomplished by bombarding embryos of

livestock with genes that produce livestock with preferred

traits. However, this technique is not efficient as only 5

percent of the offspring express the traits (Kolata, 25 July

1997). Scientists can easily alter adult cells. Thus, cloning

from an adult cell would make it easier to alter the genetic

material. A transgenic organism has had its genetic information

artificially altered. The goal of transgenic livestock is

to produce livestock with ideal characteristics for the

agricultural industry and to be able to manufacture biological

products such as proteins for humans. Farmers are attempting to

produce transgenic livestock already, but not efficiently, due to

the minimal ability to alter embryos genetically. Scientists can

harvest and grow adult cells in large amounts compared with

embryos. Scientists can then genetically alter these cells and

find which ones did transform and then clone only those cells.

Scientists also ponder the idea of cloning endangered species to

increase their population. The possibilities are endless.

However, we are actually doing much of this research for the

improvement of life for humans. Embryologist Dr. Steene

Willadsen, when talking of past research, stated, “I was checking

fences, looking for holes in the scientific fabric, ways to break

through what others considered dogma.” (Kolata, 3 June 1997).

Scientists foresee the cloning of pigs to produce organs

that humans will not reject (Wills, 1998). Also, as mentioned

earlier, livestock can produce biological proteins helping people

who have diseases including diabetes, Parkinson’s, and Cystic

Fibrosis (Kolata, 2 December 1997). Cloning also provides better

research capabilities for finding cures to many diseases. There

are also possibilities that nuclear transfer could provide

benefits to those who would like children. For instance, couples

who are infertile, or have genetic disorders, could use cloning

to produce a child. Equally important, women who are single

could have a child using cloning instead of in-vitro

fertilization. Nuclear transfer could also provide children who

need organ transplants to have a clone born to donate organs.

Cloning could also provide a copy of a child for a couple whose

child had died.

Cloning does offer some negative affects it could have to

life. The biggest problem with asexual reproduction is that

genetic diversity becomes limited. If a population of organisms

has the same genetic information, then the disease would wipe out

the population. This is because not one organism has an

advantage of fighting the disease over the other. The technique

of nuclear transfer is also early in its developmental stages.

Thus, errors are occurring when scientists carry out the

procedure. For instance, it took 277 tries to produce Dolly, and

Roslin scientists produced many lambs with abnormalities (Wilmut,

1997). This is the main reason science is holding out on cloning

humans. I also believe we should not attempt nuclear transfer to

produce an adult human until the technique is perfected.

Other arguments for cloning include if we are taking nature

into our own hands by cloning. Religious organizations consider

nuclear transfer to cause men to be reproductively obsolete

(Post, 1997). Religious groups claim that cloning defies the

rule or their belief that humans have souls. They also consider

cloning unnatural, and say we are taking the work of God into our

own hands. People question when we will draw the line for

getting involved in natural events (Bruce, 1998). There is also

a debate as to the moral rights of clones. Some say this will

occur because there is no birth of newness (Post, 1997). We

would not receive clones with such excitement as a child of a

couple who conceived naturally. If natural reproduction were to

occur, genetic variation would occur. They say cloning would

deprive someone to have any perception of uniqueness. They argue

that identical twins are not unique from each other. However,

they are new in genetic variation and unique from anything that

came before them. People also wonder what mental and emotional

problems would result if a clone were to find out that he or she

was cloned.

Although nuclear transfer produces clones, scientists

confess that they are not exact clones because the recipient egg

does not receive all the genetic information from the donor cell.

The genetic material that does not make it to the egg cell is

found in ribosomes which are present in the cytoplasm. In

addition, mutations can occur and genomic imprinting could cause

other differences.

Scientists even say monozygotic twins, or identical twins,

are not as identical as we thought. Scientists also predict that

dizygotic twins, or fraternal twins, would maintain more

similarities than clones. The reason seems that fraternal twins

grow a bond during their first nine months (Wills, 1998). This

is an example that genetics does not fully contribute to the

personality of a person. Time spent intrauterine for nine months

haves a greater effect than genetics is a good example.

Also, the statement that identical twins are unique and new

only in the sense of their new genetic combinations is absurd. I

know identical twins myself that are extremely unique, and

perhaps strive for differences. Constitutional law scholar

Laurence Tribe said that human cloning would ‘alter the very

meaning of humanity’ (Post, 1997). I think a clone would

especially find the meaning of humanity and become unique. I

think Tribe is confusing that we strive to be unique because we

are human not because we have chromosomal DNA that is found

nowhere else.

Sidney Callahan, a psychologist, argues that “the random

fusion of a couple’s genetic heritage gives enough distance to

allow the child also to be seen as a separate other” (Post,

1997). Yet I cannot stand that I look like my father when he was

my age, and currently I am under the impression that I was

conceived naturally. Thus I believe the old-fashioned way of

having kids is not giving me enough distance, so what is the

difference for a clone.

So anyone who argues that cloning disregards the laws of God

and the souls of humans, they should reconsider their views.

Cloning does not artificially produce copies of adult humans.

Nuclear transfer is the artificial making of an embryo that will

develop into an identical twin. No machine that can produce

carbon-copy humans when performing nuclear transfer is involved.

At this point, I believe we should not use cloning.

However, if we are to venture into cloning we must make many

precautions. I think the best way to do this is to research the

consequences. Yet, I do not believe cloning of animals is

acceptable. Thus, I do not think we should conduct cloning

experiment on animals. In summary, cloning is ethical, unless

there is lack of respect for the lives of animals and humans, and

for the ongoing inhabitation of life on earth.


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