Stem Cell Generation from Ordinary Cells Now Safe

WASHINGTON (Reuters) - Japanese researchers who invented a way to make powerful stem cells out of ordinary cells say they have now found a safer way to do it.

Shinya Yamanaka of Kyoto University in Japan and colleagues invented a new way to transform ordinary cells into embryonic-like stem cells called iPS cells, using a ring of genetic material called a plasmid.

Working in mice, they generated induced pluripotent stem cells, or iPS cells, and said they believe the method can work in people, too, and is an important step toward a new field called regenerative medicine.

Stem cells are the body's master cells, giving rise to all the tissues, organs and blood. Embryonic stem cells are considered the most powerful kinds of stem cells, as they have the potential to give rise to any type of tissue.

But they are difficult to make, requiring the use of an embryo or cloning technology. Many people also object to their use, and several countries, including the United States, limit funding for such experiments.

In the past year, several teams of scientists...