1971-1977 Telomere

Telomere Fuses Terminal transferase Commentary

Alexey Olovnikov, Elizabeth Blackburn, Carol W. Greider, Joseph G. Gall, Jack W. Szostak genetics

Telomere

• The ends of each chromosome
• have tiny caps called “telomeres”
• composed of a sequence
• of six nonsense nucleotides
• repeated hundreds of times
• to protect the ends from deteriorating
• or from fusing with other chromosomes
• but that are shortened with each copy.
• Regular DNA replication
• stops at the telomeres, so that sometimes
• the telomeres are broken;
• therefore,
• another mechanism, the telomerase enzyme,
• replenishes the telomeres;
• however,
• in humans, telomerase is active
• only in germ cells, stem cells,
• and some types of white blood cells.
• Body cells are on their own and after
• enough divisions, their shortened telomeres
• results in damage and senescence.

Fuses

• Random genetic mutations
• are inevitable; having a finite lifetime
• may prevent cells from going wacko.
• Shortening telomeres
• are like fuses; when they burn
• to the end, their chromosomes blow.

Terminal transferase

• Why couldn’t there be an enzyme
• that guards against growing old?
• Sadly deteriorating ends
• of chromosomes need repairs
• but our own telomerase
• isn’t active everywhere it’s needed.
• Let’s admit we’re not perfect,
• considering we tend to fall apart
• before we reach a hundred years
• like a machine that’s never oiled.
• Let’s say it were possible to lubricate
• without risking cancerous growths.
• Why then would we choose to accept
• imperfections; why not become superhuman?
• The question is whether being human
• and being godlike are compatible. Probably not.
• The scary prospect of death
• may be nothing compared to living forever.