Cloning refers to the copying of identical genes, cells, or organisms derived from a single ancestor. It is also the process through which a clone is derived, whether it occurs naturally or is artificially induced in a laboratory. Cloning of genes and cells to create many copies is a common procedure essential for biotechnological and biomedical research.
Cloned organisms are those that have resulted from asexual reproduction or without the joint help of males and females. Theoretically it is possible to recreate an entire plant, animal, or human from a single cell, and that is why cloning is often called a process of carbon-copying. Just as a carbon-copy is identical with the original, a clone would also be identical to the original creature.
Why Is Cloning Possible
Cloning, or asexual reproduction, is possible because each cell of a living organism contains all the information that is necessary for the development and nurturing of the entire organism. Thus if somehow man is able to use the genetic information from a single cell, he can create the entire creature out of it. This information resides on the genes.
A living cell is a very complex factory, having (what we can call) tens of thousands of machines and hundreds of thousands of components. Out of this let us consider only two major parts: the cell and the nucleus. The nucleus contains many components, with the most important being the Chromosomes. The chromosomes carry the DNA, the carrier of genetic information. The DNA on a single human cell contain enough information to fill an entire set of the Encyclopedia Britannica (30 volumes). These DNA contain all information about how his organs are going to function, and numerous such information needed to make him a functioning living being.
Though all cells contain the same number of Chromosomes, the reproductive cells contain only half as much. Thus when a sperm and ovum unite, half of the chromosomes are contributed by each parent. Thus in each child there is a mixture of ancestral chromosomes, and this mixing process ensures that most of the harmful genetic diseases are kept in control.
Since each and every cell contains all the information necessary to create the entire creature, allowing the cell to multiply and grow should result in a mature creature from a single cell. This is the principle behind cloning. This is how a plants grow from stems cut from them. This is how a single cell, when accidentally separated into two, gives rise to identical twins. The capacity for a type of cloning is built into these organisms. But even here there are some restrictions.
To get a new plant from a stem through vegetative reproduction, it has to have a certain minimum maturity. A stem lying outside this range would not grow roots and leaves in most cases. Similarly, twins are formed in humans only when certain favorable conditions are present, but not otherwise.
Though cloning of mammals succeeded only in 1977, scientists received their clue to the possibility of cloning much easier from nature itself.
- Main Article: Vegetative Reproduction
Although sexual reproduction is common in plants, most also reproduce asexually through what is commonly called vegetative propagation. For example, when a farmer breaks off a branch from a tree and obtains an entirely new one by planting it in the ground, it is an asexual reproduction. Thus it is a type of cloning. There are a number of plant tissues capable of this process, for example rhizomes (potato), runners (strawberry), stem pieces (willow), and seed (dandelion).
There are a variety of asexual multiplication in plants and trees, and farmers and gardeners use these methods regularly and without any surprise. That is because this capacity for direct cloning has been built into these plants by the Creator himself.
In humans also a similar process takes place when twins are formed in a mother's womb. Once the sperm and the ovum merge with each other, a single cell is formed. This cell then grows and divides itself into a bi-cellular stage. Then these grow and change into a four-cellular stage, eight-celled organism, and so on. All during these stages of growth, all these cells are intimately united with each other, and are a single person -- the child to be born. However, sometimes mistakes do take place during cell division.
In rare cases, the cells not only divide themselves, but also get separated from each other. Each fragment then starts functioning as an individual human being, and grows to the full human baby from that stage. This is why some women give birth to two or more identical children. They are identical because they came into existence by the division of a single cell. They are copies of each other.
When a single cell splits up into two identical cells or more, and when each one grows independently, this is cloning. Though the sexual process produces only one life, the splitting up produces more than one person asexually. We do not marvel at this because this is a process for which God himself has given the capacity to human beings. Further, HE himself has made provisions for the safe growth of the multiple embryos. It is totally different matter, however, to mimic these in a scientific laboratory.
Though certain kinds of cloning are already available in nature, this does not automatically justify man's attempt at cloning other organisms. The very fact that only certain types of cloning are available in nature indicates some kind of a boundary. Boundaries are indicated in Genesis when God says that living creatures should reproduce after their kind.
The need for respecting boundaries are indicated in the Scriptures where mixing of certain plants and animals are forbidden. These boundaries are also indicated through the commands that forbid humans from having sexual relationships with animals.
It must be noticed that in each of the forbidding commands above, there are no natural physical barriers. Thus multiple seeds can easily be sown together. Human-Animal sexual relationship is physically possible. God has not created any physical barriers to prevent these. But perhaps all the results would ultimately be disastrous. We do not known the full implications, but it is very clear that what has been forbidden in the Scriptures places certain moral boundaries around our actions.
The Scriptures forbid many activities not because they are impossible, but rather because they are improper. They are wrong either morally, or technically, or even in both ways.
Why Is Cloning Difficult
Cloning is not difficult at all in those plants and animals in which God has given them a capacity for doing so. We only have to observe certain restrictions like choosing a mature stem in the case of plants.
Cloning is more difficult, but still possible, in certain reptiles. It must be noted, however, that many of these reptiles already have the capacity for asexual reproduction. Since the capacity of asexual reproduction is built into them, this results in relative ease in cloning them in the laboratory. The case of mammals and humans is different.
In mammals and the humans the cells acquire specific responsibilities after crossing a threshold. This might be after the I6-cell stage, or a bit before or after that. Before reaching the threshold, which varies from organism to organism, all the cells are identical. A mature replica of the original creature can be reproduced from any of these cells at this stage. But after crossing the threshold, the cells start to specialize. It is the same original cell with all the original DNA but now one becomes a skin cell, and yet another a nerve cell.
Once a cell starts functioning as a specialized cell, it somehow turns "off" all the genetic information not needed by it. Thus even though it contains all the original genetic material, all the non-relevant information becomes dormant. Thus even if it is grown by some process, it would not be able to grow the original creature out of it. Skin cells would multiply only into skin cells, and nerves only into nerve cells -- though they actually contain all the chromosomes and all the genetic information inside them. This is the difficulty in cloning mammals from their matured cells.
In mammals and humans only their reproductive cells (sperms and ova) make all the information available that resides on their chromosomes. Thus it has been possible for scientists to perform many kinds of surgical manipulations upon sperms and ova, but the same could not be done on mature non-reproductive cells due to their specialization.
Specialization (after a certain growth) is a definite barrier kept by the Creator in all kinds of organisms. Cloning a new creature from these specialized cells has been a very difficult task because of this barrier. But now even this barrier has been overcome in some mammals, though only time will tell whether it will ultimately result in good or bad.
The idea of cloning was popularized in 1932 when Aldous Huxley wrote his book Brave New World. It must be noticed that Huxley was here drawing the picture of a godless mankind that tries to control its own future.
Though Huxley was the first to use the concept of cloning in a book, work leading to its success started in the last century itself in the form of reproductive technologies. The first recorded successful experiment in reproductive technology was performed by Walter Heape. He was a Cambridge University scientist, and he was able to transfer an embryo into the uterus of an animal other than its natural mother. This took place as far back as in 1890. This is why in the introduction of this book I mentioned that much research has been going on secretly for very long in the field of reproduction.
By 1930 scientists realized that this approach can be used commercially for breeding animals with desirable traits. Thus from 1930 onward scientists began to fertilize animal ova in laboratory glassware, which were then implanted into surrogate animals. This process has become so common that today most domestic cows produce offspring using this technique. This process eventually led to what are now called "Test Tube Babies". These are babies produced by fertilizing the ovum in laboratory glassware and then by implanting them into a woman.
Cloning the same animals was more difficult than this, and the first success came in 1952, sixty two year after the first successful animal experiment in artificially assisted reproduction. In '52, Robert Briggs and Thomas King were able to extract tadpole cells and develop full frogs from them. From here onward there were plenty of developments in animal and plant cloning. Of these two, the plant cloning became a commercial success in the form of tissue culture. Animal cloning, on the other hand, could not succeed in mammals and other higher organisms. Nor could it succeed in humans, though many scientists were fascinated by the whole idea. There are records showing that many scientists secretly kept trying to clone humans.
In the nineties many scientists were successful in cloning mammals using the twin-formation phenomena seen in nature. They would take a single-celled fertilized egg, allow it to become bi-cellular, and would them carefully separate these two cells from each other. These are again allowed to multiply to two, and are then divided again. This way they were able to produce many offspring from a single fertilized egg. However, they discovered that even here there are practical limits to how many clones can be produced from a single embryo.
In the nineties itself scientists at the George Washington University in the USA were able to do the same kind of embryonic cloning in humans. However, all this cloning in animals and humans was achieved with the help of reproductive cells or embryos. The desire in their hearts was to clone mammals and humans using ANY cells from the body. The greatest hurdle, as we discussed before, was specialization.
The greatest hurdle in producing a clone from other cells was their "specialization". Though each cell or an organism contains ALL the information needed to develop and sustain the full organism, all this information has gone into a state of "sleep" in these cells. Consequently, a skin cell remembers only how to grow more skin cells, and a cell from other parts of the body remembers information only for growing into parts of that organ.
Dr. Ian Wilmut of the Roslin Institute near Edinburgh in Scotland, however, was successful for the first time to "waken up" the sleeping genes, and break the barrier. He realized that if ALL the genes in a specialized cell are forced to "sleep" and then given a chance to start the process of life from the beginning, then perhaps all of them would "wake up". Soon the scientific team tried this approach and succeeded in doing what others had been dreaming for decades.
The Procedure: To achieve his goal, Dr. Wilmut took cells from the udder of a six-year old pregnant sheep. He then placed these in a salt solution and "starved" them. In this hostile environment the genes were not able to function, so almost all of them went into a state of "sleep" or hibernation.
Then Dr. Wilmut took unfertilized ova from another sheep and removed the nucleus from each one of them. Once this was done, he fused one "sleeping" cell each with one nucleus-less ovum. Since the purpose of the ovum is to provide an atmosphere in which a nucleus can grow into an adult animal of that species, this atmosphere provided by the ovum woke up the sleeping genes. This combination started behaving like an embryo, and this was implanted into a third sheep. There it grew, and a sheep named Dolly was born after the gestation period was over.
What was surprising here is that Dolly had only one parent, instead of the normal two. Only the sheep that provided the nucleus is the parent (or twin) of the offspring. The two others have no parental relationship because they only provided the support, but no genes came from them. Thus was born Dolly the first mammal to be successfully cloned.
While the news of Dolly was being discussed by the media, another news came that Dr. Don Wolf of Oregon in USA successfully cloned two monkeys -- though full details are yet to be given to the press. Once all this news became public, guesswork already set into motion about cloning humans. Though scientists are very cautious and secretive about discussing their work, it is not difficult to guess that work on human cloning has already been going on secretly and illegally in many laboratories.
Though President Bill Clinton immediately hinted at the plan for some kind of ban on cloning experiments, and though there is an outcry from scholars all over against cloning, none of this might halt cloning experiments. History is our witness that many scientists continue to do illegal research in spite of all kinds of bans. Also, many large drug, cosmetic, and other consumer product manufacturers continue to explore these areas illegally because there is enormous money and profit for them in these breakthroughs.
The best example for the above observation is Dr. Ian Wilmut himself. He carried his work with government funds, and the total expenditure came to over US$ 200,000. Now the government of his country has announced withdrawal of financial support. But what is intriguing is that this support would be withdrawn only 14 months after he made announcements about the success of cloning. Obviously, these months would be used for further developments, and by the time the cut off date arrives, the atmosphere might change and everyone would favor cloning!