SCIENCE CHANGES

The word "clone" comes from the Greek klon, which means "bud" or "twig". So in biology cloning means the possibility of "duplicating" the genetic heritage of any living being. Thus, for example, viruses, bacteria, molecules, organisms and even plants or animals can be duplicated.

It is a genetic engineering technique that serves to reproduce millions of identical copies of a fragment of DNA (or a complete genetic makeup), even starting from a single cell. However, a clone, more generally, is an individual genetically equal to another. Cloning is quite frequent in nature, in particular in single-celled organisms that reproduce by simple division, without mixing the genetic material with other individuals, or in plants.

Dolly the sheep, the first official clone, came into the world on July 5, 1996. The name is a tribute to the well-known actress Dolly Parton, due to the fact that the biological material used in the cloning process came from the udders of an adult sheep. Dolly and the first clones that came after her (mice, cats, chickens, cows, mouflons), marked a turning point, especially in those years: something - it was said - could radically change the way we understand reproduction, at least regarding animals, breeding, feeding.

Even with regard to endangered species, we would add today. BEYOND THE MORAL. However, cloning has limitations. Dolly died in 2003, but she spawned, thus proving to be "identical" to the other sheep. However, he had arthritis problems, and for some this was the demonstration of a structural defect in the clones: premature aging.

Ian Wilmut, the scientist who gave birth to it, stated at some point in his research career that clones have a very high percentage of malformations.

Animal cloning brings with it the idea of human cloning.Beyond the ethical objections,which in any case have led to

very restrictive legislation on the subject, (as far as we know) observed in all the countries of the world where research is carried out (officially), the future of clones and this technology is uncertain.

It is certainly an important step forward in biology and medicine because it opens new scenarios for the treatment of many serious human diseases such as diseases of the nervous system (Alzheimer, Parkinson, Stroke) because our brain is much more similar to that of primates than to that of other mammals.

Some of the economic advantages of cloning are evident: if all identical cattle and with the same particular characteristics were bred in the stables, abundance, food safety and quality would be guaranteed.

Some research concerns for example animals genetically manipulated to produce drugs, with the idea that they could provide active ingredients with a simple milking.

MAMMALS AND CLONING.

Why is cloning not a "good" method for reproducing among higher animals?

Take mammals, for example: evolution has traveled on the thread of adaptability. Being identical, without ever changing the basic model, does not help: for some, it is only useful when the environmental conditions are extreme and always the same.

When there are organisms that find themselves in this situation, and are already casually endowed with a genetic recipe that allows them to survive, they must always keep it the same in order not to risk disappearing.

Having always the same copies in a competitive situation such as that which occurs in a richer and more variable environment, on the other hand, is almost certainly suicide.Because subsequent generations are prevented from finding new solutions to new problems (which is adaptability): a genetically flexible competitor would be able to prevail, changing behavior, eating habits and so on over time, and for the clones the game would be lost, forever.

IS CLONING MAN A RISK?

Despite the sensational declarations, cloning therefore has at least one seemingly unsurpassed conceptual limit: the individual is young, in the sense of "new", but old - in the sense that the genetic heritage of the original has already undergone the worsening changes linked to the years that lived.

There is a high failure rate: 227 embryos were created to reach Dolly. Only 29 have grown to the point where they can be transferred to the womb of a surrogate mother, and only one has made it. In subsequent experiments, on mice, the results were better: 1 in 100 clones survived. On humans ... some experiments have finally led to the formation of stem cells and, as far as we know, it has never gone further: the "recipe" is however in the public domain, at least in the scientific field.

Speaking of Dolly, Ian Wilmut never clarified the aspect of aging.

However, he raised the alarm on another question, perhaps related: the majority of animal clones, both in the womb and after birth, have shown to have functional defects and malformations. Many died shortly after birth; the cloned mouflon in Italy lived only one year. Some American research has suggested that it may depend on the gene that encodes the Oct4 protein, and which also influences other genes, which does not work and regulates incorrectly in 90 percent of clones that derive from adult donor cells. Research continues, but everything still seems to be in the realm of hypotheses: in short, cloning does not seem to be the result of exact science for now.

Cloning studies continue since it can be useful in the animal sector and allows you to quickly obtain animals with the best qualities but the Cloning a human being is useless and scientifically unmotivated. Human cloning has sometimes been proposed to improve the genetic qualities of humanity: for example, by cloning highly successful individuals in sport, music, the arts, science, literature, and politics. The obstacles and drawbacks for this purpose are many and insurmountable, at least in the current state of our knowledge.

The genome can be cloned, but the individual himself or the phenotype cannot be cloned. The character, personality and characteristics other than the anatomical and physiological ones that make up the individual are not precisely determined by the genotype.

Our children will continue to be born through the fertilization of a woman's egg cell by a man's sperm, and therefore through that extraordinary biological process that ensures the genetic variability indispensable for surviving in a world that changes continuously.