December 17, 2003	Wednesday	Shawwal 22, 1424

WASHINGTON, Dec 16: The only researchers to publicly show that they have cloned a human embryo said on Tuesday that they had successfully repeated the experiment, growing an embryo to the 16-cell stage.

Researchers at Advanced Cell Technology of Worcester, Massachusetts, have also repeatedly created embryos using a process called parthenogenesis — using only a human egg cell and no sperm, and without cloning.

The company says the experiments, reported in the January issue of Wired magazine, are not breakthroughs but a natural progression of its efforts to create human embryonic stem cells to use for medical treatments.

“It’s not a scientific advance,” ACT medical director Dr. Robert Lanza said in a telephone interview.

But he said the researchers had managed to replicate experiments reported in late 2001, in which they used cloning technology to create a human embryo that grew to the six-cell stage. They also created more advanced embryos, called blastocysts, using parthenogenesis.

Sheep, cattle and pigs have all been cloned using an egg cell and an adult cell from another animal.

Even more successful were the parthenogenesis experiments — in which five of eight human eggs were coaxed into growing into blastocysts. At this stage — approximately 100 cells — an embryo can be mined for its stem cells.

The stem cells — nature’s template for all cells — can become any sort of cell or tissue in the body.

Scientists hope the cells may one day allow custom-made tissue transplants to heal damaged hearts or cure diabetes by replacing dead pancreatic cells.—Reuters