Experts have found a way to repair a defective gene that encourages cancer and to make it kill off tumors, a Swedish scientist said on Friday.

More than half of all cancer tumors have a mutated gene called p53. In a healthy state the gene helps repair the DNA damage that leads to cancer in the first place. Without that function, tumors may grow uncontrollably.

But a research team at Karolinska Hospital in Stockholm has succeeded in repairing the gene, paving the way for a drug to combat virtually any form of the disease.