Bubble Boy's Secret

DAVID WAS BORN WITHOUT AN IMMUNE SYSTEM, and for 12 years he lived inside a sterile plastic bubble that protected him from the outside world. Now, nearly 10 years after David's death, doctors have isolated the faulty gene responsible for his rare condition. In an article in Cell, researchers report that the mutation causes immune cells to produce defective copies of a receptor for interleukin-2, one of the most important molecular regulators of the body's defense system. Eventually scientists hope to transplant normal copies of the gene into the blood cells of affected children, thereby curing them. The research might also lead to new strategies for restoring the damaged immune system of people who suffer from AIDS.