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Molecular biology

Introduction:

In the past few years, a lot of research in the medical field has evolved considerably. MOLECULAR BIOLOGY, which specializes in studying the genetics, is one of these areas. Also research in the genetics field has been classified into several sections. The most significant of these branches is called cloning, which has led to widespread controversy throughout whole world. Scientists have used this expression to explain many processes of interest in the manufacture of several identical copies of biological materials such as genes and the cells of plants and animals. Therefore, the cloning of the gene enabled scientists to find new treatments for incurable diseases such as cancer and diabetes with the help of many industries of the biotechnology. Here cloning was used to produce human embryos using a process called somatic cell nuclear transfer (SCNT). In this process the nucleus of the female`s egg is taken out and substituted for by another nucleus from the cell of a fully grown body, for example, an udder cell. In reproductive cloning, asexual reproduction is used to create an embryo. So there is no need for sperm and an egg to join. The probity of creating a cloned human raised a good deal of interested concern when scientists in Scotland announced the production of a cloned sheep named Dolly, on February 24th 1997. The scientific team at the Roslin institute in Edinburgh successfully used the technology of SCNT to remove the nucleus of a sheep's egg and exchange it with a nucleus from a cell of the mammary gland of a different mature sheep. This process resulted in a new embryo which was, in turn, transposed to another sheep`s uterus. In addition, the same process was undertaken for 277 embryos and just one of them was successfully born. Although, the live expectation of a pastured sheep is approximately 12 years, Dolly lived for just 6 years and scientists say that this was related to being a cloned animal { Judith & Erin, July, 2006}.

Certainly, there are several types of human cloning, such as the cloning of DNA, therapeutic cloning and reproductive cloning. Usually, the media concentrates on two types of human cloning in their reports - therapeutic and reproductive cloning. This project will focus mainly on reproductive cloning. First of all reproductive cloning will be defined. Then, an explanation of how reproductive cloning be done will be introduced. Secondly, a brief demonstration of the purpose of reproductive cloning will be provided. Finally, the ethics of reproductive cloning will be mentioned.

Definition of reproductive cloning:

Reproductive cloning is known as the creation individuals who have the same genetic characteristics. Every new single built individual is a copy of the initial. Monozygotic duplicate twins are normal clones. "Clones have the same genetic characteristics in the nucleus as the section which has the chromosomes of each cell in their bodies. Therefore, the nuclei of two clones have the same DNA and the same genes in their nuclei". {National Research Council, 2002}

Every cell and egg in the body has a quantity of DNA responsible for releasing energy. This is entitled mitochondria. In addition, mitochondria have their private DNA and clones. So, a proper reproduction should have similar DNA inside both nuclei and mitochondria, with the knowledge that scientists have also used the expression of clones to indicate towards a singles that have the same nuclear DNA and different DNA as part of the mitochondria.

The procedure of reproductive cloning:

There are two methods that have been used by scientists to make cloned mammalian live births. "Both methods require the implantation of an embryo in a uterus and, after that, a period of pregnancy and childbirth. However, the cloning of humans or animals is not a recognized tool that is used to derive embryos that are genetically identical and suitable for implantation" {National Research Council, 2002}.

Scientists in the National Research Council, 2002, claim that the first method used for reproductive cloning is:

Cloning occurs by using the technique of somatic cell nuclear transfer (SCNT) {1b}. This plan of action first begins with chromosomes which must be taken out of an egg in order to produce an enucleated egg. Then, the chromosomes are exchanged with a nucleus taken from a somatic cell of the individual or the embryo to be cloned. There are many different ways to obtain this cell. This can either be from the individual directly, from a grown culture cell or from tissue kept in a freezer. Secondly, the egg is encouraged to begin to divide. This leads to a form of blastocysts or (a pre-implantation embryo). The third step is to move the blastocyst into the uterus of a host animal. If the implantation is successful, this in turn may enhance its next stage of growth. Therefore, this animal will be considered to be the reproduction of the individual that was the grantor of the nucleus. This means that its nuclear DNA characteristics have been transferred from just one genetic parent.

The second method used for reproductive cloning:

Cloning by using the split of the embryo: this operation uses a technique called (in vitro fertilization (IVF). The process occurs outside the female`s body in order to produce a zygote. When the zygote is split into two and then four similar cells, then the cells can be dissociated and allowed to grow separately, but as similar blastocysts. Lastly, the blastocysts can be implanted in the uterus of the female host. This operation cannot be done again because of the limitations of the possible growth of the cells. Therefore, embryo dividing can result in just two similar mice and perhaps only four similar humans.

Furthermore, the DNA in embryo dividing is donated by germ cells from two different individuals (an egg from the female and a sperm from the male). So, embryos such as these are likely to be formed normally or by standard IVF and have two parents with the same DNA as the mitochondria {National Research Council, 2002}.

The purposes of reproductive cloning:

There are several reasons to use a cloning for a reproductive object. First of all, cloning is used in agriculture and livestock improvement by using genetic modification which is an excellent method of having very good growth in livestock and improving the production of high quality milk. Also, it helps scientists produce medicine or vaccine in milk without the need to make natural sexual contact. Furthermore, scientists use mammals in their research. For example, mouse cloning is used in order to raise their knowledge of different principal mechanisms related to biology. {National Research Council, 2002}

Moreover, some people have the desire to use reproductive cloning for different aims such as:

Furthermore, scientists have analyzed potential grounds for using human reproductive cloning depending on their level of explanation. For instance, it is stated that using human reproductive cloning to find a genetic relationship to the parent in the case of infertility, would be more justifiable than trying through sexual contact with a fertile body in order to select an appropriate genome.

In addition, it is suggested that there is no need for a cloned child birth to provide tissue for transplantation purposes. For instance, in vitro fertilization is used to produce embryos. These embryos can be used for appropriate transplants. So, in future, the production of tissue for transplantation might be allowed by using stem cells which are released as a result of nuclear transplantation. {National Research Council, 2002}

Ethics of reproductive cloning:

The subject of human cloning has attracted the attention of many people, not only in terms of reproduction or research, but also with regard to many different aspects. It is suggested that people have not considered this issue as a new scientific technology. However, they claim that this subject has touched the principal aspect of mankind. The theory of cloning has raised the identity issue and the meaning of children by birth. Also, a significant question has been raised with regard to the link between society and human cloning. The ethics of human cloning will be addressed here briefly.

The first point in these ethical debates related to identical and personal troubles. It is possible that cloned children face several serious troubles of identical regard, for two reasons. First because they will have almost the same genetic characteristics as a person who is already alive or who lived before. The second is because of the prospect of their futures may be misleading due to the regular contrast between the cloned child and the initial donor.Secondly, there is a fear that the reproduced children would be the first people whose genetic characteristics might be chosen in advance. These children might be considered as mass production which was designed for manufacturing purpose and the parents must get ready to believe them as they are. Such an outlook with regard to children could generate the idea of commercialization and the industrialization of human procreation.Thirdly, there is the possibility of a new eugenics. If the cloning process was successfully achieved this, in turn, might lead to the promotion of individual eugenics, both by preventing genetic deformity that may occur when human reproduction is done by chance, or by keeping and sustaining of the characteristics of particular genes.Furthermore, "reproductive cloning is possible to be some problems related to kinship and family relationships between generations and family members. For example (father could become "twins brother" to their "sons" & mothers could give birth to their genetic twins) therefore, this may lead to some difficulties for family life". (THE PRESIDENT`S COUNNCIL, 2003). Finally, there is also the possible impact on the general public. For example, cloning in terms of producing children affects not only the contributor, but may also affect the internal community which is satisfied and supported to carry out this activity. Even the application of this activity on a limited scale may affect the way society views cloned children.

Conclusion:

There is an intense debate among those interested in this type of research, in spite of the success on the part of scientists in the use of this technique to create a number of other animals. However, the effectiveness of the process is still unreliable and the results of the development are still abnormal {Judith & Erin, July, 2006}. Moreover, although there are different reasons for using the technique, such as improving the livestock and give the opportunity for infertile parents to have children, there are still very significant reasons for stopping it. For example, the identical trouble and its impact on society. Moreover, almost all organisations have banned this technique, particularly for the creation of children because it is still unsafe and ethically objectionable (THE PRESIDENT`S COUNNCIL, 2003).