Heart Valve Grown From Stem Cells

A  British team has grown a human heart valve from stem cells—a breakthrough certain to ignite as much controversy as hope. Sir Magdi Yacoub, professor of cardiac surgery at Imperial College, tells the Guardian that growing a whole human heart from stem cells is less than a decade away: "I wouldn't be surprised if it was some day sooner than we think."

A 3 cm wide valve, grown from human bone marrow, will be tested in an animal later this year, and valves similarly grown could used in humans within three years. Such replacement valves are more functional than artificial valves and will not be rejected. Sir Magdi’s work with stem cells is so advanced it has been described as “on the fringes of the possible." (More stem cell research stories.)