Researchers Take Heart From Manipulated Mice

Just when you thought you'd heard just about everything about gene research — scientists have supposedly isolated every predisposition from breast cancer to sugar addiction — a group of California doctors claim to have found the DNA strand responsible for the industrialized world's number one killer, heart failure. In a report released Thursday, the team of UC San Diego doctors told of mating mice genetically engineered to contain the gene phospholamban, or PLB, which they believed was responsible for heart failure, with mice that lacked the PLB gene. The resulting offspring did not develop heart failure. They also created mice carrying a defective form of PLB; in that experiment, the offspring produced by mating those mice with the mice bred to develop heart failure had a normal life span with no side effects, the researchers said. While there's no evidence yet of the gene in people, the team says that the finding could one day translate into a cure for human heart disease.

But TIME science reporter Janice Horowitz cautions that while speculating on medical cures can be as tempting as a hunk of cheddar to a mouse, the public shouldn't get trapped into generalizing about research performed on mice. "What goes on with lab mice is many, many steps away from what goes on with humans," says Horowitz. "And the work we're doing now with gene therapy is only the tip of the iceberg. It'll be a long time before these things pan out into medical cures."