ClubEnsayos.com - Ensayos de Calidad, Tareas y Monografias
Buscar

Description of the method "Therapeutic cloning"


Enviado por   •  4 de Diciembre de 2014  •  2.023 Palabras (9 Páginas)  •  216 Visitas

Página 1 de 9

Ana Dosta

Leslie Lenert

Guided Research

May 9, 2012

THERAPEUTIC CLONING

Throughout history, medical science has been developing to the benefit of human beings. Due to the increase of diseases during the past years, medical science has been developing techniques that offer great possibilities toward the cure of many disorders in health and diseases. One of these techniques, called “Therapeutic Cloning”, is to create human embryos and use them as raw material for therapeutic purposes. “Therapeutic Cloning” represents a hope of living for many people who suffer disorders in health and diseases like paralysis, organ failure, Parkinson’s, Alzheimer’s, cancer, osteoporosis, cirrhosis liver, restore myocardial attack, counter aging and sickle cell anemia. Although Therapeutic Cloning offers great potential to help human beings, it is essential to take in mind ethical and moral considerations that surround it.

It was in 1997 when in Edinburgh, Scotland, the scientist Wilmut announced the first cloning of Dolly the sheep through technology called Somatic Cell Nuclear Transfer (SCNT). A year later he announced the cultivation of stem cells using the same technique (SCNT) by scientist James Thomson. And in 2001, the company “Advanced Cell Technology” announced the cloning of human embryos (Chan 114).

Society began to hear of cloning when the case of the sheep Dolly in Scotland was announced. People are terrified and are incensed when they hear that human beings can be duplicated. However, cloning therapy is not to copy a human being and create another one like it. Therapeutic cloning is to create an organ from a living being. In cloning there is not fertilization, and nothing is implanted in a uterus to create a child. Therefore, therapeutic cloning is to create human embryos and use them as raw material for therapeutic purposes (Murnaghan).

There are several steps to make cloning for therapeutic purposes. First, the cell has a nucleus. A nucleus contains genes which are extracted from a cell taken from the human body. This procedure is known as Somatic Cell Nuclear Transfer (SCNT). Second, the nucleus is removed from any cell in the laboratory and now is one cell without a nucleus. Third, the core of the first step is introduced into a one cell coreless so that this cell has the nucleus that had been removed in the second step, calling this procedure “substitution”. Fourth, the fused cell is developed in a laboratory to obtain cells known as a “blastocyst”. This “blastocyst” has an inner and an outer layer. The interior contains many cells known as “embryonic stem cells” which, when they are integrated into the body, are known as “pluripotent cells”. Finally, the stem cells are susceptible to becoming tissue without problems of rejection by containing the same genetic material (Murnaghan).

Therapeutic cloning has a series of advantages and disadvantages to consider before it is applied. Some of the advantages are: “pluripotent cells” that are mentioned above, which can replace all cells of the body except the cells of the embryo and with this any organ or tissue can be regenerated. The risk of a patient rejecting these cells is low, because they contain their own genes and the same type of protein. Containing the same kind of proteins, decreases rejection considerably (Murnaghan).

Another of these advantages is that many lives could be saved because patients wouldn't have to wait to get a transplant and also could get a new organ instead of an organ from a donor, whose functionality may be reduced (Robinson).

On the other hand, there are some disadvantages. One of the main difficulties of therapeutic cloning is that hundreds of attempts are required for fusion to be successful. And there are also moral difficulties in applying therapeutic cloning, since an embryo is destroyed to obtain stem cells and this is seen as an abortion because the embryo could be a human being. Finally, there are ethical difficulties because in reproductive cloning SCNT cells are not used and there are fears that a scientist can try to conduct human cloning laying aside therapeutic cloning (Murnaghan).

Therapeutic cloning can be used to treat and/or cure diseases. For example, the cell replacement therapy for therapeutic cloning could create different types of tissues to counteract or cure various diseases and/or genetic deformities. One of these tissues is the tissue osteoblasts that can be used to re-generate the spinal cord and thus a paralytic person can walk, and also can be used to treat the disease osteoporosis, that it is lack of calcium in the bones of human. The novo bodies are for transplantation, these organs can be transplanted to help severe burns or atherosclerosis that it is inflammation of the walls of arteries. Cells of the pancreas organogenesis, the creation of the cells therapeutic cloning leads these cells to be transplanted to the pancreas, to treat hyperglycemia related to diabetes. Neurodegenerative diseases like Parkinson's disease, characterized by deterioration of neurons resulting in constant tremors and muscle stiffness. In addition, with replacement of cells in therapeutic cloning it hopes to assist in the treatment of cortical atrophy, which it is loss of cerebral cortex or Alzheimer's disease. Another one is cancer; the somatic cells have applications to distinguish whether the type of cancer grows out of epigenetic or genetic defect; and to can restore the epigenetic profile DNA donor. Some of other diseases that can be treated and/or cured are cirrhosis liver, restore myocardial attack, sickle cell anemia, counter aging, diabetes, glaucoma, blindness, Down syndrome, AIDS, lymphoma, stroke, cystic fibrosis, infertility (Kfoury 113, 116, 120; Robinson).

According to Charlotte Kfoury, therapeutic cloning in animals for research purposes is to create animal models of human diseases and subsequent to this model will make clinical trials to find a treatment. One of these models has been created in a mouse to cure Parkinson's disease. The test was that the mice received neurons made of their own clones showing significant signs of improvement (113, 115).

In Parkinson's disease, cells that control muscle movement die; these cells produce dopamine which allows smooth running of the human body. Therapeutic cloning removes the nucleus of these cells and inserts into the egg without a nucleus, and it develops an embryo. These stem cells produce dopamine that is the neuron missing in cells with Parkinson's disease. However, if these neurons mismatched genetically they won't survive and then mice won't recover (Kfoury 113).

This

...

Descargar como (para miembros actualizados)  txt (13 Kb)  
Leer 8 páginas más »
Disponible sólo en Clubensayos.com