Why're stem cells evergreen?
The main gene that directs embryonic stem cells to remain young has been found. This may discard the need to abort embryos to grow cells for new therapies.health and fitness Updated: Jun 26, 2003 13:39 IST
The principal gene responsible for the youthful state of embryonic stem cells has been discovered, reported journal New Scientist.
The breakthrough is likely to contribute to turning ordinary adult cells into those with the properties of human embryonic stem cells (ESC) and would phase out the need to destroy embryos to harvest the cells for new medical treatments.
Being "pluripotent", ESCs are unique and are capable of differentiating into the different cells in the body, with great potential for treating damaged or diseased organs. But until now, scientists were vague about whether a stem cell renews itself or develops into a new kind of cell.
The gene found in mouse ESCs and some human equivalents appears to be the "master gene", co-ordinating other genes to allow stem cells to multiply limitlessly while still retaining their ability to differentiate. It has been aptly christened Nanog after the land in Celtic myth, called Tir nan Og, whose inhabitants remain forever young.
"Nanog seems to be a master gene that makes ESCs grow in the laboratory and in effect, this makes stem cells immortal," says Ian Chambers, member of the team at the Institute for Stem Cell Research in Scotland.
Nanog is likely to direct the process of ESCs renewing themselves by switching on and off other genes, and the pattern of gene activity co-ordinated by this gene is typically seen in human ESCs about the fourth or fifth day of development.
Researchers have predicted a more immediate use of the key gene would be to enable the medical profession to grow 'millions and billions' of ESCs from existing samples. These could then more safely be used in humans, as they would not have been exposed to the cocktail of chemicals currently needed.