A Key to Immortality?
Inside each cell there are genes for an enzyme known as telomerase. This is an enzyme that in stem cells can maintain telomere length and help the cell to divide indefinitely. However, in our differentiated cells, for most of the time, these genes for telomerase are switched off. But if there was some way of switching them on, perhaps they could maintain telomere length, and hence extend cellular lifespan and perhaps our own? Could the key to immortality already be with us? Are they the genes that control the production of these enzymes? Another key question is whether telomere shortening is a cause of ageing or merely a sign of it, in the way that wrinkles and liver spots are signs of advanced years. If shortening is a sign then maintaining telomere length won't alter cell longevity.
These questions have certainly got scientists scratching their heads and thinking, but there is at least one good reason (at the moment) why activating telomerase genes might not be such a good idea. The enzyme has been found to be active in cancerous cells. It keeps tumour cells proliferating, for without it the mutated cells would eventually die as their telomeres progressively shorten. It therefore appears that if we were able to activate telomerase to extend cellular life, and possibly our life spans, this might actually have the opposite effect. Telomerase activation could increase our cancer risk by stopping mutated cells from dying.
However, there are several research efforts looking to control the activity of telomerase in cancer cells. If scientists can manage telomerase activities it might stop cancer cells from utilizing the enzyme. This in itself would be a boon to the biology of ageing, because it may provide us with new weapons against cancer, and whilst not guaranteeing immortality, it would help extend the lives of cancer sufferers.