In 1962, John Gurdon, at the age of 29, performed an extraordinary scientific experiment: he extracted the nucleus of a cell from the intestine of a frog and introduced it into an egg cell that he had previously emptied of its genetic material. This gave rise to a tadpole that was a clone of the frog to which the intestinal cells belonged, demonstrating for the first time that the genome of mature cells can be reprogrammed and direct the embryonic development to produce perfectly normal adult individuals.

Similar attempts were made for decades in other animals. Everyone will remember, for example, the famous Dolly the sheep, the first mammal cloned by a similar procedure in 1996. But it was not known for sure how such reprogramming takes place, or why it is so difficult to achieve. In late 2006, the Japanese researcher Shinya Yamanaka astonished the world by answering these questions, although he actually went much further: he reprogrammed fully specialized cells, such as the skin cells of the tail of a mouse, in the laboratory . And he did it in an admirably simple way, activating only four genes. With that maneuver, the specialized cells were reprogrammed into cells virtually identical to those found in the earliest stages of an embryo.

Cell reprogramming is one of those things that, in theory, should not happen. Textbooks explain that embryonic cells, as they increase in issue to enable the rapid growth of the embryo, "differentiate" (specialize) until they reach maturity as liver cells, brain cells, heart cells, and so on. It had always been thought that this process is irreversible, that there is no turning back, but Gurdon's experiments showed that the cellular clock can be slowed down. Yamanaka, 45 years later, helped to explain it and also opened up the possibility of applying this knowledge to the cure of human diseases. The award of the 2012award Nobel Prize in Medicine to these two researchers is a magnificent capstone to this exciting story of scientific discovery; the fact that only six years have passed since the findings of the Japanese researcher indicates the importance of these breakthroughs.

Taken together, Gurdon's and Yamanaka's discoveries highlight the fascinating world of embryonic development biology, which with the progress of Genetics and Cell and Molecular Biology allows challenges to be posed that were unthinkable years ago. The application of these advances to medicine could lead to new treatments for diseases that are incurable today. We do not know when, but the day will come when patients with diabetes, Parkinson's disease or many other degenerative processes will be cured by procedures that, to a large extent, are due to the discoveries of Gurdon and Yamanaka. That is why today we celebrate the fact that the committee Nobel Prize has recognized their work.