Are Telomeres the Key to Immortality?

   

Thanks to recent breakthroughs in genetics research, we may be on the verge of discovering a fountain of youth in our own genetic material In 2009, three researchers—Elizabeth Blackburn of the University of California, San Francisco, Carol Greider of Johns Hopkins University, and Jack Szostak of Massachusetts General Hospital—won the Nobel Prize in Medicine for their work linking the aging process to telomeres. Telomeres are clusters of DNA that cap the chromosomes of complex organisms, protecting the rest of the genetic code during cell division. As cells age, these caps grow smaller, exposing the DNA to breaks and mutations that can lead to cancer or cell death.

    

    These discoveries hint at a connection between telomeres and the broader aging process. People of an advanced age do tend to have cells with shorter telomeres when that cell is of a type that replicates frequently. Analysis of the white blood cells of Hendrikje van Andel-Schipper, a Dutch woman who lived to the age of 115, revealed extremely short telomeres on such cells compared with cells that divide infrequently (such as nerve cells). Similarly, patients who suffer from accelerated aging diseases have also been shown to possess much shorter telomeres than unaffected individuals of a similar age. So can we prevent or even reverse aging by preserving our telomeres? Maybe. While early results indicate a correlation between shorter telomeres and aging, this does not by itself imply a causal relationship. It could be that the two processes simply coincide or even that aging itself is what causes telomeres to shrink. And even if the relationship is causal and significant, how do we take advantage of this fact? Gene therapy is still in its infancy. Worse still, telomerase, the enzyme that inhibits the decay of telomeres, is also present in 90 percent of cancerous cells; by preventing cell death, we may grow malignant tumors. It’s worth considering that this relationship serves a purpose. Our genetic code may have evolved to encourage cells to die in order that they might not grow into cancer. If there is indeed a fountain of youth, it may behoove us to blaze a different path on our way there.