Cloning

Natural cloning

In the Natural , the cloning is nothing more than a Mode of reproduction among all those at the disposal of the living beings. It is even most widespread since it relates to all the cells Procaryotes (division), almost all the Eucaryotes Unicellulaire S (Mitose) except for those which practice the reproduction (utilizing the Méïose), but also of many plants and animal Pluricellulaire S.

Certain animals cut into two can give two genetically identical individuals as it is the case at the hydre S. Moreover, the cells of the complex organizations generally reproduce by cloning.

The cloning can be natural at the plants; it is in this case generally called vegetative Multiplication. It takes place by emission of Rejet S, by natural Marcottage, natural division of Rhizome S or Stolon S. Certain plant species emit Rejet S, like the olive-tree. When the initial Ortet ages, it emits rejections on the circumference of its stock. These Ramet S becomes then autonomous and separates between them at the time of disappearance of the initial stock with time. Others, like the strawberry plant, produce Stolon S, branches of which the final bud enracine in contact with a favorable Substrat and reproduced thus, by natural Macottage, a plant identical to the plant mother. By natural Bouturage of the pieces of plant can push back if they are found placed under good conditions, and give again a complete adult plant.

Vegetable or animal artificial cloning

Vegetable cloning

In horticulture and culture, the techniques of reproduction of plants per cloning can be techniques practiced under greenhouses or on the ground, which are applicable at many Dicotylédone S because of their abundance of Méristème S. They are practicable on some Monocotylédones also (the banana tree can multiply by Rejet S, the cane with sugar by Bouturage). One can quote the Greffage, and the Bouturage which do not exist naturally in nature and other techniques this time inspired of the natural vegetative multiplication: (the Layering, the Thinning of rejections or the division of Rhizome S and Stolon S,…)

These techniques can be also techniques of laboratory. It is the in vitro Culture of Méristème S or other parts of the plant producing of the Embryo S then complete seedlings (see somatic Embryogenesis and zygotic Embryogenesis). In vitro techniques are the only ones which can be employed for monocotylédones like the Palmier-dattier, the Palmier with oil.

Animal cloning

In the animal field, a step is crossed at the 20th century thanks to the cloning starting from cores of differentiated cells reimplanted in beforehand énucléés Ovocyte S. This technique with the still low rate of success and which did not succeed that at some species is with its stammerings. Problems of accelerated ageing seem to be able to be connected to the state of the Télomère S. Peut-être that will prevent the disappearance of several species like the giant Panda or the Gorilla of the mountains.

The Chinese embryologist Tong Dizhou, was the first with cloner an animal (a carp) in 1963, 33 years before the ewe Dolly. It published its research in a Chinese scientific magazine which does not seem to be translated at the time.

This technique allowed to cloner the following animals:

Carp: 1963, first artificial clone resulting from this technique.
Dolly (ewe), a ewe, first mammal clone in 1996 (and born on February 24th 1997) starting from a specialized cell. She died in 2003 of a lung disease which the ewes normally with 11 have or 12 years.
“Netti” and “Ditto”, two monkeys rhesus clones in 1997.
“Cumulina”, a Mouse clonée in 1997.
“Marguerite”, a Cow, clonée by INRA in 1998.
“Millie”, “Christa”, “Alexis”, “Carrel” and “Dotcom”, 5 small Pig S, clones in March 2000.
“Noah”, a Gayal, in January 2001, a wild species of ox, first animal in process of extinction.
Bull X: March 2001
“Carbon Copy”, or " Copy carbone" a cat, fine clone 2001.
Mouse: 2002
Six rabbit S, clone in 2002 by INRA.
“Idaho Gem”, “Utah Pioneer”, “Idaho Star”, three mules, clonées in 2003.
Deer: 2003
“Prometa”, a mare, clone in 2003.
“Ralph”, the Rat, clone in 2003
Drosophila: 2004
“Little Nicky”, in 2004, a cat, first produced clone with commercial goal.
Doctor Hwang, announces to have clone the first human cell, but a few months later it is obliged to acknowledge trickery.
“Snuppy”, a Dog, clone in 2005 in South Korea by discussed the doctor Hwang.
“Paris Texas”, a Horse, clone in 2005.
the first primate is clone in 2007

All these experiments showed that the cloning of the males is in general more delicate than that of the females. Moreover, for still unknown reasons, only 5 to 10% of eggs manufactured and reimplanted viable clones or in apparent good health produce. One does not include/understand either why certain cells of an organization are clonent better than others.

A second step is crossed before the new millenium by the cloning of second generation (obtaining organization clones starting from other organizations clones) on Souris, then a Taureau.

In 2007, there exists nearly a thousand of pigs clones and nearly 3000 bovines.

Surprises of the cloning

For good cloner a mouse this which consists in transferring the core from one of its cells in an ovule dénucléé-, better is worth to use an old cell than all fresh. It is the conclusion of an nippo-American team published in Nature Genetics. the rate of success of the cloning can be improved of a factor 10 (passing from 4% with nearly 40%) if, instead of transferring the core from an original cell, one chooses that of a differentiated cell, in fact, a white globule. -->

The clones are not certified copies

Only the genetic material of the core is transferred at the time of a cloning. DNA mitochondrial remains that of the receiving cell. In the same way, of the environmental factors can modify to become to it embryos. In practice the animals clones differ on several parameters and are less resembling that identical twin monozygotes (having same genetic inheritance) watch an interest always growing of the public for the technique. Arnold Schwarzenegger, governor of the California militated in favor of the human cloning. The opponents with the cloning seem all the more in a hurry to arrive at an international consensus. The the United States, with more than fifty other countries, signed a call to a total ban of the human cloning. Another text prohibiting only the reproductive cloning was written by the Belgium and was supported by more than twenty country, of which the Russia, the Japan, the the United Kingdom, the South Korea and the Denmark. Research in favor of the reproductive human cloning still expresses a search Fantasmatique, of the man, for his Immortalité.

End 2002, the movement raëlien, via Clonaid, affirmed to have carried out the cloning of human beings but no scientific proof of their existence was brought.

It is allowed scientifically that the identity to be it is not summarized with its Génotype, which means that it is impossible to simply produce two identical beings by duplicating a genome. Moreover, the case of identical twin already informs us on what could be the reality of a “reproductive” cloning human: this reality is precisely not alarming (still that many cultures are wary of the twins, incarnation of a dangerous imitation) and would be a kind of invitation to science.

But all this raises questions ethical S, philosophical, and religious important at this beginning of 21e century leading to many debates.

This new form of generation presents for example legal difficulties concerning the legal statute of the clone. In particular when one speaks about “therapeutic” cloning, which implies that the clone is put at the service of others by its partial destruction, even total. From this point of view, certain raised ethical questions can join those of IVG.

In May 2005, researchers of South Korea and the United Kingdom announced the first clonings of human embryos at ends of therapeutic research.

Applications

Therapeutic cloning

The therapeutic human cloning (CHT), or transfer of core of somatic cells, is a technique of production of material living usable like " médicament" , generally for a Clerc's Office and to replace a destroyed or deteriorated body. The finality of this technique is genetic compatibility with the patient ensured by the cloning. However, this technique is subjected to the polemic owing to the fact that it is a cloning. Some see there a more acceptable form by its medical purpose, and others a worse form due to the statute of object of the embryo. The technique is a cloning, i.e. one includes the core of an adult somatic cell in an ovocyte énucléé to obtain an embryo, and cells totipotentes known as also original cells. Indeed, this cloning is with an aim of producing lines of cells embryonic stem cells of Blastocyste (5th at the 7th day after fecundation) likely of beings grafted without causing rejection. Thus bodies " neufs" , or of the cells with strong capacity of reproduction, can thus be manufactured, for a Clerc's Office. The concept, born at the end of the 20th century, was still not concretized in 2004. It is possible that it is obsolete before this realization, because of progress on these special cells, that it seems possible to obtain without recourse to their indirect manufacture by cloning (regenerating therapy by original cell).

reproductive Cloning

The reproductive human cloning (CHR) is a cloning aiming at reproducing a clone to find the memory of a person.

(drawn from Y. Brun & Y. Schumacher, " the bioethics delimits the statute of the human cloning " , Pierre University & Marie Curie, Methodology: Biology & environment, Paris, 2006.)

Legislation

With UNO

The March 8th 2005, the general meeting of the United Nations decided to prohibit the cloning, even with the fine therapeutic ones. The " Declaration of the United Nations on the cloning of the beings humains" , nonconstraining, was adopted with 84 votes for, 34 votes against and 37 abstentions. Among the countries which were opposed to this declaration are the France, the the United Kingdom, the Norway, the India, the Japan, the Canada and the China.

Belgium

Currently, there exists in this country no specific regulation relating to research on the human embryo, but a royal Decree of 1999 fixes the conditions of approval for the centers of FIV. The constitution of embryos, indeed, is not authorized that in these approved centers. For the moment, the scientists in charge of research projects bringing into play human embryos must undertake their work in a center of approved FIV, and, the protocol of research must obligatorily receive the authorization of the ethical Committee of institutions (universities, organizations). But the government recently worked out a bill concerning research on the embryo. The purpose of this project is to define the conditions under which research on supernumerary embryos could be carried out and even considers, in certain cases, the creation of embryo for purposes of research, without specifying for the moment which would be the methods of this creation. A thing is sure: all research will have to then be the control object as well local as federal. This bill must be discussed soon at the Belgian federal Parliament.

France

The French legislation on the cloning counts among most severe: thus, article 16-4 of the Civil code French proscribes any cloning, with goal eugenic, reproductive or therapeutic:

'' No one cannot attack the integrity of the mankind. ''

Toute practical eugenic tending to the organization of the selection of the people is prohibited .
Is prohibited any intervention having for goal to give birth to a child genetically identical to another person alive or deceased .
Without damage of research tending to the prevention and the treatment of the genetic diseases, no transformation can be brought to the genetic characters with an aim of modifying the descent of the person.

The former minister for Research, Roger-Gerard Schwartzenberg, deposited on May 24th, 2005, in front of the office of the National Assembly, a private bill aiming at repealing the article of the law of August 6th, 2004 on the bioethics, which prohibit the therapeutic cloning. A petition, signed by 10 scientific personalities, including two Nobel Prize of medicine, François Jacob and Jean Dausset, was given on June 17th, 2005 to the president of the National Assembly in order to support this proposal.

Legislation Original cells in France

PUBLIC HEALTH CODE (New Lawful part)

R2151-1 article (inserted by Decree nº 2006-121 of February 6th, 2006 Article 1 II Official journal of February 7th, 2006)

Are in particular likely to allow major therapeutic progress, within the meaning of the article L. 2151-5, research on the embryo and the embryonic cells continuing a therapeutic aiming for the treatment of particularly serious or incurable diseases, as well as the treatment of the affections of the embryo or the fetus.

South Korea

In February 2004, the team of the professor Hwang Woo-suk is the first with cloner an human embryo for the scientific research. These results were partially disputed in December 2005 by an independent study, part of the results having been falsified.

The United Kingdom

In August 2004, the Authority on the fertilization and the human embryology (HFEA) authorized professor Miodrag Stojkovic, of the university of Newcastle to cloner of the human embryos at therapeutic ends of research on the original cells. Another authorization was granted in 2005 to professor Ian Wilmut of Roslin Institute of Edinburgh. In May 2005, the teams of professors Alison Murdoch and Miodrag Stojkovic, based in Newcastle announced to have clone an human embryo.

External bonds

Argumentations for and against the cloning
Dignity, ethics and cloning
the cloning in Europe and in the world
the situation of the cloning in the United States
Animations showing various types of cloning

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