Humans ‘could regrow body parts’

A little girl looks with some bewilderment at the X-Ray films of body parts put on display at an exhibition. Photo: CH Vijaya Bhaskar

The fabled human spare parts kit may someday become a reality, thanks to scientists who claim to have discovered a gene which could allow regrowing of damaged body parts.

An international team, led by The Wistar Institute in Philadelphia, has found that the p21 gene could block the healing power still enjoyed by some creatures like amphibians, but lost through evolution to all other animals. By turning off p21, the process can be miraculously switched back on.

In their research, the scientists found that mice lacking the p21 gene gain the ability to regenerate lost or damaged tissue. Unlike typical mammals, which heal wounds by forming a scar, these animals begin by forming a blastema, a structure associated with rapid cell growth.

According to them, the loss of p21 causes the cells of these mice to behave more like regenerating embryonic stem cells rather than adult mammalian cells. This means they act as if they creating rather thane mending the body.

They turned off the gene in mice which had damaged ears and they regrew them. While they say it is early days, there is nothing theoretically different about applying the same process to humans, ‘The Daily Telegraph’ reported.

Lead scientist Professor Ellen Heber-Katz said, “Much like a newt that has lost a limb these mice will replace missing or damaged tissue with healthy tissue that lacks any sign of scarring.”

“While we are just beginning to understand the repercussions of these findings, perhaps, one day we’ll be able to accelerate healing in humans by temporarily inactivating the p21 gene.” Ellen said.

“In normal cells, p21 acts like a brake to block cell cycle progression in the event of DNA damage, preventing the cells from dividing and potentially becoming cancerous.” Ellen added.

“We propose that any future therapy would involve turning off p21 transiently during the healing process and only locally at the wound site. This might be done through locally applied drugs. This should minimise any side effects.” Ellen said.

The findings have been published in the ‘Proceedings of the National Academy of Sciences’ journal.