IN the fertile fields of genetics, the road to living longer could provide new solutions for old problems, or at least perpetuate the scientific search so that that progressive deterioration called aging is prolonged, along with a better quality of life.

Many researchers are convinced that human beings can live to be 120 years old, but they also know that in order to do so, many factors come into play, including nutrition, medical attention, the environment, culture, exercise, motivation and genetics, among others.

Life expectancy has gradually increased throughout history, but it was during the last century and the beginning of the current one that the possibility of living to the average age of 75 or older became a reality.

Despite the inequality that exists throughout the world, knowledge of the causes of most diseases, vaccines, antibiotics, the evolution of diagnosis techniques, the advance of surgery and the development of pharmaceutics and dietetics are among the factors resulting in a much longer life expectancy than our ancestors.

Paradoxically, according to scientists, the longer people live, the greater possibility there is that their body develops diseases that stem from cellular degeneration.

Many of those dedicated to the research and development of knowledge on increasing life expectancy and improving health have focused their studies precisely on that area: the cells. Slowing deterioration of the whole can be done, presumably, by slowing the aging of the parts, especially the most miniscule. Specialists believe that the greatest signs of aging have their microscopic basis in cellular aging. When a cell divides, it should duplicate all of its components, including chromosomes, thus giving way to identical offspring.

In the ends of chromosomes, a fundamental piece or sequence may be found that controls the life of all the cells in a body: the telomere. With each division that the cell undergoes to give way to a new one, this segment becomes smaller. This telomere erosion marks, like an implacable biological clock, the maximum time that a cell may live. It is estimated on average that each cell may divide 50 times. Then, the chromosomes will have shortened enough to reach a critical point, and initiate the process of cellular death.

The size of a telomere is related to the number of times that the cell has divided. This process occurs in normal somatic cells; however, in germinal cells, as in embryonic ones, the presence of an enzyme called telomerase prevents that erosion, adding telomere repeat sequences. It restores the telomere sequence, thus prolonging cell life, maintaining its ability to duplicate itself.

The death of cells may appear to be an unfortunate occurrence, but, as with the entire human body, it responds to a delicate and complex synchronized system. When something fails in the system, and a cell that was supposed to die continues to live, mutational defects may appear, alterations in its future replications. Many scientists accept the theory that the majority of cancers and other degenerative diseases are produced by the persistence of cells that leap over that critical point of telomere erosion; they continue to live and degenerate.

It has been demonstrated that this enzyme is expressed in tumorous cells, enabling them not to lose telomere, not to become unstable, and not to die. In this case, the ensured life of the cancerous cell becomes a threat to the body, given that these fatefully long-living cells engender a countless number of new tumorous cells.

Some theories hold that developing telomerase inhibitors could combat tumors, given that those cells would become unstable in terms of the length of their telomeres and would die.

The differences in telomerase activity in the process of cell division for normal somatic cells and the behavior of tumorous cells is what is putting telomerase at the center of current research.

On the one hand, there is a search for their benefits – given that their activity prevents cellular death—, and on the other, the immense possibilities that open up with respect to research on anti-cancer therapies that use telosmerase inhibition to prevent the duplication of tumorous cells.