Body’s ‘Doomsday Clocks’ Count Down to Death, or Cancer


Credit: Courtesy of Hesed Padilla-Nash and Thomas Ried, National Institutes of Health.

Body’s ‘Doomsday Clocks’ Count Down to Death, or Cancer

Every cell inِ your body hasِ its ownِ Doomsday Clock, ticking downِ the number ofِ times itِ canِ safely divide.
Like theِ plastic aglets onِ the tips ofِ shoelaces, telomeres keepِ the chromosome fromِ fraying.
If scientists couldِ make drugs toِ control telomeres, theyِ couldِ perhaps treat diseases ofِ aging asِ well asِ cancer.

Telomeres Aplenty

Researchers haveِ known sinceِ the 1930s thatِ telomeres cap chromosomes, butِ it wasِ notِ until theِ 1970s thatِ they figured outِ what thoseِ caps areِ made of.
They foundِ it inِ a pond-dwelling organism called Tetrahymena.
Human cells, inِ contrast, haveِ a mere 46 chromosomes.

Telomerase Trouble

When a cell divides intoِ two daughter cells, itِ hasِ to copy itsِ DNA.
Having telomeres onِ the ends ofِ the chromosomes means thatِ noِ important genes areِ cut off.
If telomeres andِ telomerase don’t doِ their jobs properly, diseases canِ develop.