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CLONE - also spelled clon population of genetically identical cells or organisms that are derived originally from a single original cell or organism by asexual methods. Cloning is fundamental to most living things, since the body cells of plants and animals are clones ultimately derived from the mitosis of a single fertilized egg. More narrowly, a clone can be defined as an individual organism that was grown from a single body cell of its parent and that is genetically identical to it.

Plants that are able to propagate by asexual means produce genetically identical plants that are clones. Cloning has been commonplace in horticulture since ancient times; many varieties of plants are cloned simply by obtaining cuttings of their leaves, stems, or roots and replanting them. A vast array of fruit and nut tree varieties and innumerable ornamental plants represent clones.

The body cells of adult animals and humans can be routinely cloned in the laboratory. Adults cells of various tissues, such as muscle cells, that are removed from the donor animal and maintained on a culture medium while receiving nutrients manage not only to survive but to go on dividing, producing colonies of identical descendants. By the 1950s scientists were able to clone frogs, producing identical individuals that carry the genetic characteristics of only a single parent. The technique used in the cloning of frogs consists of transplanting frog DNA, contained in the nucleus of a body cell, into an egg cell whose own genetic material has been removed. The fused cells then begin to grow and divide, just like a normal fertilized egg, to form an embryo.

Mice were first successfully cloned in the 1980s, using a procedure in which the nucleus from a body cell of a mouse embryo is removed from the uterus of a pregnant mouse and transplanted into a recently fertilized egg (from another mouse) whose genetic contents have been evacuated. The cell is cultured artificially until it divides and becomes an embryo. The embryo, which is composed entirely of cells derived from the single implanted nucleus, is artificially implanted into the uterus of another mouse that brings it to term.

Cloning a new animal from the cells of an adult - as opposed to those of an embryo,  is considerably more difficult, however. Almost all of an animal's cells contain the genetic information needed to reproduce a copy of the organism. But as cells differentiate into the various tissues and organs of a developing animal, they express only that genetic information needed to reproduce their own cell type. This tended to restrict animal cloning to the use of embryonic cells, which have not yet differentiated into blood, skin, bone, or other specialized cells, and which can more easily be induced to grow into an entire organism.

The first success in cloning an adult mammal was achieved by a team of British researchers led by Ian Wilmut at the Roslin Institute in Edinburgh, Scotland, in 1996. After having already produced clones from sheep embryos, they were able to produce a lamb, named Dolly, using DNA from an adult sheep; Dolly was put to sleep through euthanasia in 2003 after being diagnosed with a severe lung infection. To create the clone, the nucleus of a cell from the mammary gland of an adult sheep was implanted in another sheep's unfertilized egg whose nucleus had been removed. The key to the procedure is to synchronize the cell cycle—i.e., the ordered sequence of events that occur in a cell in preparation for division—of the mammary cell with that of the egg. To achieve this, before implantation the mammary cell is deprived of nutrients; this stops its cell cycle, thus preventing it from dividing. The nucleus is then implanted into the recipient egg and fused to it, and an electrical current is applied to simulate the burst of energy that occurs during fertilization. The egg begins dividing normally and becomes an embryo, which is implanted into another ewe. The lamb that is born is a clone of the donor of the original mammary cell.

The practical applications of cloning are economically promising but philosophically unsettling. Animal breeders would welcome the chance to clone top-quality livestock. Genetically engineered animals could be cloned in large numbers to increase the production of drugs or human proteins that are useful in fighting disease. Clones are also highly useful in biological research because of their genetic uniformity.

The cloning of human beings is a subject fraught with ethical and moral controversy. If cloning can ensure the infinite replication of specific genetic traits, a judgment would need to be made as to which traits are desirable and therefore worthy of perpetuation. The persons empowered to exercise such judgment would be in a position to change the course of human development.

The use of recombinant DNA technology to manipulate and change genes is sometimes called gene cloning. See genetic engineering.

Cloning - A group of genetically identical organisms produced from a single parent cell by asexual division of that cell   -   for example by vegetative reproduction in plants or parthenogenesis in animals. Gene clones - identical copies of a gene - these are produced by genetic engineering.  CLONING - CLONE - also spelled clon population of genetically identical cells or organisms that are derived originally from a single original cell or organism by asexual methods.

Cloning is fundamental to most living things, since the body cells of plants and animals are clones ultimately derived from the mitosis of a single fertilized egg. More narrowly, a clone can be defined as an individual organism that was grown from a single body cell of its parent and that is genetically identical to it. - Cloning is the creation of an organism that is an exact genetic copy of another. This means that every single bit of DNA is the same between the two.

Mammalian Cloning

The possibility of human cloning was first raised when, in 1996  - 7, Scottish scientists at the Roslin Institute created the now late and much-celebrated sheep Dolly. This provoked much Worldwide interest, but tinged with some concern because of its scientific, religious and ethical implications. 

The official opinion of the Roman Catholic Church is that: Every possible act of cloning humans is intrinsically evil. And could never be justified. All religious and ethical tradition, reaffirms this viewpoint, which is largely based on an interpretation of the, Adam & Eve, creation story. Many religious zealots, still believe that Humankind emerged from just two people - Adam & Eve.

This mammalian cloning event, was cited by the  Science Magazine, as the scientific breakthrough of 1997. It also spawned uncertainty over the very meaning of what Cloning actually is.  Cloning, is now a generic term that covers various procedures and outcomes. The term Cloning was traditionally used by scientists to describe different processes for the natural replication of biological material. When a cell splits, it produces an exact copy of itself, this is natural cloning.

It is only a matter of time before a human being will be cloned and allowed to grow to full fruition. Human embryos have been made, it is said, but they have only been used for other experiments. Twins are actually Nature's own Clones.

Celebrity Sheep Died at Age 6

Dolly, Finn Dorset Sheep, the first ever mammal to be cloned from adult DNA, was laid to rest by lethal injection on Friday, Feb. 14, 2003. Dolly had been suffering from lung cancer, crippling arthritis and general melancholy. Although most of her type of sheep live to be about 12 years old, a post mortem examination clearly indicated that she was otherwise quite normal. Her medical problems could not be attributed to the cloning process. The unknown donor from which Dolly was cloned, had actually died some years prior to her creation. Dolly was a mother to six lambs herself, but these were created the old way.

UK researchers have successfully made cloned human embryos, following in the steps of South Korean scientists who created 30 human embryo clones last year.

CLONING   -   Cloning is what cells do every second of the day. They split to multiply and 99.99% of the time two exact copies are produced. When a cell does not multiply correctly, a Mutation or a Deformity could be produced.

Genetically identical cells, or organisms are derived originally from a single cell or organism, by asexual methods. Cloning, in the modern sense is also an asexual process and  is fundamental to most living things, since the body cells of plants and animals are clones ultimately derived from the mitosis of a single fertilized egg. More assiduously, a clone can be defined as an individual, though there may be many.

To bring forth new life in mammals and other creatures, the female produces an egg and the male a sperm. These two entities contain all the genetic material and genetic instructions from each individual. These, through whatever method are mixed and they fuse together, incorporating into a new individual or entity. The sperm is said to have fertilized the egg. Separately both the sperm and the egg are just bits of biological material, and they are described as being acquiescent. They also can be described as, being sterile. Fused together they become, fertile, and a new life. 

This new life, the mixture of the cells - the egg and the sperm joining, is called at first, a zygote - pronounced "zye-goat". This develops into an embryo and it grows and grows by splitting and splitting again, through the asexual process of natural cloning. It soon develops further and become a fetus, and then a baby,  which is eventually born, and an offspring is brought into the world.

To 'fertilize' an egg, that will produce a clone, the substance of the egg and the sperm are not used. Eggs are removed from the female and scientists suck out the female cells, the genetic material and genetic instructions from the egg,  and in reality only use the casing or shell that carried this material. The shell is called the zona pellucida, and is a soft gelatinous coat.

By the same method the cell of another individual is introduced into the egg. This means that cell material from another animal is taken from them, like a stomach-cell, and injected into the now empty egg zona pellucida, (the casing). This empty egg zona pellucida, is used as a surrogate vessel to grow and develop the newly introduced, somewhat alien, cell material. But it does work and does grow, under the right conditions.

Most specimen cells, taken from an individual, have been programmed to be whatever they are. For example,  a liver cell is a liver cell, a skin cell is a skin cell and so on. But all cells still contain the programming or information for all other cells, this information is just switched off. 

As a fetus, in the beginning of life, all cells have the potential to be anything but chemical instructions turn them into, say heart cells, and a heart is grown. Or brain cells and a brain is grown. The cells are not turned into any particular cell, it is that the chemical instruction just switches all other cell attributes off. This ongoing process hopefully turns into an individual. 

So once the specimen cell material is injected into the casing, the egg is almost as it was; a shell with biological material in it waiting to be fertilized. As a sperm cannot be introduced, as this would not only defeat the object, but would not work, scientists put it through another process. 

A small electric current is passed through it. Before this, it is in its quiet or acquiescent state, if left it would do nothing, but eventually decay. The small current resets all the values, and returns the cell material back to where ALL genetic attributes are switch on.  Due to the environment the cell is in, inside the egg casing, and the natural enzymes present, the cell acts as if it is a normal conception. The cell material splits into two, again and again, this eventually grows into an individual and a clone is produced.

MUTATION  -  For a myriad of reasons any living creature, from a Group B streptococci to a blue-whale could be prone to mutate. Whatever it should mutate into, is a lottery to some extent, but whatever it is, whether droll or a disaster, it is a fact of life that it happens; a phenomenon. 

Below is a real picture of a guy with SIX fingers on each hand. The combination perhaps, of the genes from both his parents that he inherited, that gave him a propensity to be different from the norm. By some fluke of nature he is different from about 99.999% of the rest of us. 

Should he ever breed with a woman who also has extra digits, there would be an even greater propensity for their offspring to have twelve fingers. Should  these children then have more kids with other children with twelve fingers, a new species of human could evolve. 

Mutation  -  A change in the hereditary material of the DNA of any organism, which results in some physical change in the organism or its offspring. Only a mutation in a germ cell is inherited by the offspring; a change in any other cell, the somatic cell, affects only those cells produced by division of the mutated cell. Mutations provide an important source of genetic variation in the population on which natural selection can act, which eventually results in the evolution of new specie types.

Mutations may occur quite by chance      - spontaneous mutations     -    or they may be caused by certain chemicals, ionizing radiation, such as X-rays, and even by ultraviolet light. 

You heard it here first. Consider although MRSA microbes have been around for over fifty years, and we might wonder what exactly allowed them to mutate to be resistant to antibiotics, what about mobile phone radiation. With 35% of the population carrying MRSA in their noses, what effect might this, now everyday radiation have. Not only to any wayward microbes, but what about young men carrying their phones in their pockets close to their scrotum.

BBC NEWS Tuesday, 11 January, 2005, 07:48 GMT Parents should ensure their children use mobile phones only when absolutely necessary because of the potential health risks, an expert is warning. 

Two rare white tiger cubs have been born at West Midlands Safari Park.

It is the first time the rare breed of Bengal tiger has been born in captivity in Britain. White Tigers were a Mutation. Now they have become a separate species.

Deformity in biology, is an irregular or abnormal structural development. Malformations occur in plants and animals and can be due to a myriad of reasons. The behavior of biological development is regulated in such a way that very few malformed organisms are produced. Those that are found may, when properly studied, answer questions on normal development. The science of teratology - a branch of morphology orembryology, is concerned with the study of these structural deviations. Generally, abnormalities can be often be observed quite early in the embryonic stage. Deformities may be caused by abnormal or mutant genes, through environmental conditions, infection, drugs, radiation but most frequently, by a reciprocal activity from a combination of any of the above.  

In Vitro Fertilization

IVF, also called test-tube conception, is a  medical procedure in which mature egg cells are removed from a woman, fertilized with male sperm outside the body, and then inserted back into the uterus for normal gestation. Although in vitro fertilization with re-implantation of fertilized eggs has long been used in animal breeding, the first successful birth of a human child from this method was, carried out by Patrick Steptoe and R.G. Edwards of Britain, in 1978.

Of course this is a very simplified version of events. Cloning has been known about for many years but it has also taken many years of research and experimenting to achieve any good results. The body cells of adult animals and humans are routinely cloned in the laboratory, not only to survive but to go on dividing, asexually  producing colonies of identical descendants. 

This is for various research projects and other experiments. Where once, a hundred years ago, doctors experimented on cadavers to just see what was beneath the skin. Now they need to explore further to find out how things work. One day they will look into the nucleus inside a nucleus, and then maybe even further. 

By the 1950's researchers were able to clone frogs, producing identicals, that carried duplicate genetic characteristics of only a single 'parent,. The techniques used in the cloning of frogs consist of transplanting frog DNA, contained in the nucleus of a body cell, into an egg cell whose own genetic material has been removed. The fused cells then begin to grow and divide, just like a normal fertilized egg, to form an embryo. 

But in some other creatures it is not so simple. In 1996, the first success in cloning an adult mammal was achieved by a team of British researchers led by Ian Wilmut at the Roslin Institute in Edinburgh, Scotland. After having already produced clones from sheep embryos, they were able to produce a lamb, named Dolly, using DNA from an adult sheep. Dolly was conceived at the 277th attempt. This means, that eggs were taken from a several donor sheep and one by one each the biological material was removed from inside. Then a cell from the mammary gland of a donor sheep was implanted into it.

The cloning of Human Beings, is a subject obviously laden down with ethical and moral debate, and some hullabaloo Cloning could ensure the infinite replication of an individual, along with their specific genetic traits. Objectively, some judgment might then need to be made to determine if certain traits are desirable, and therefore worthy of perpetuation. The problem here is who might, or would exercise such judgment. And who would pick the judges? Not only could this change the natural course of human development, but it might be considered to be against God's will, or indeed against the rules of Mother Nature.

We would only comment that the history of medicine is littered with ethical and moral debate, and much hullabaloo. Much has been said about the depravities of such procedures like blood transfusions, organ transplants

Ten years ago, the Arthritis Research Campaign played a major part in setting up the Twin Register. This month it earmarked another £100,000 to help medics maintain its thriving database. And in the years in between much has changed in the way that scientists regard common musculoskeletal diseases.

An Israeli woman has given birth to a healthy baby girl after undergoing an ovarian tissue transplant, following cancer treatment that left her infertile.

IVF - also called test-tube conception medical procedure in which mature egg cells are removed from a woman, fertilized with male sperm outside the body, and inserted into the uterus of the same or another woman for normal gestation. Although in vitro fertilization with re-implantation of fertilized eggs (ova) has long been widely used in animal breeding, the first successful birth of a human child from in vitro fertilization, carried out by Patrick Steptoe and R.G. Edwards of Britain, did not take place until 1978.

In vitro fertilization is generally undertaken only after an exhaustive evaluation of infertility has been made. A number of the candidates for IVF are women who suffer from blocked or absent fallopian tubes; others are men with low sperm counts or couples whose infertility is unexplained. IVF procedure includes the recovery (by needle aspiration) of mature eggs and the incubation of the eggs in a culture medium, as well as the collection and preparation of sperm and its addition to the medium. Fertilization generally occurs within 12 to 48 hours. The potential embryo is then placed in a growth medium, where it is observed periodically for division into two-cell, four-cell, and eight-cell stages. During this period the mother receives progesterone to prepare her uterine lining for implantation of the embryo. The embryo, which at this point is known as a blastocyst, is introduced through the cervix into the uterus, in which the blastocyst seems to float free for about three-and-a-half days. If the procedure is successful, the embryo implants itself in the uterine wall, and pregnancy begins.

Of the problems that have been noted in IVF procedure, successful implantation seems to be the weakest link. One possible explanation for this problem is that the in vitro zygote develops at a slower rate than the embryo in vivo  - i.e., within the body, and hence, the growth of the in vitro zygote and the development of the endometrial tissue are not perfectly synchronized.

In vitro fertilization has been a source of moral, ethical, and religious controversy since its development. Although members of all religious groups can be found on both sides of the issues, the major opposition has come from the Roman Catholic church, which in 1987 issued a doctrinal statement opposing IVF on three grounds: the destruction of human embryos not used for implantation; the possibility of in vitro fertilization by a donor other than the husband, thus removing reproduction from the marital context; and the severing of an essential connection between the conjugal act and procreation.

Other ethical questions raised more generally have involved the fear of experimentation with human fetuses. Related techniques, such as the freezing of eggs, sperm, or embryos for future implantation, have also raised a number of as yet unresolved moral issues.