A LITTLE tinkering may be all normal human cells need to make them grow
limitless supplies of tissue for transplant, studies suggest. The work
challenges the widely held belief that most mammalian cells are intrinsically
mortal.
While bacterial cells can replicate forever, human cells can only divide a
limited number of times without an enzyme called telomerase, which repairs the
ends of chromosomes. Even with telomerase, many cells grind to a halt after a
few dozen divisions. Biologists thought that this “replicative senescence” was a
fundamental property programmed into each cell.
Apart from cancer cells, the only human cells supposed…
