Isolation of Rare Gene May Boost Cancer Research : Medicine: Scientists hail discovery of mutation that causes fatal childhood disease. They see it having broad implications.

Isolation of a gene mutation that causes a rare and devastating childhood disease may help scientists learn the fundamental processes that cause normal cells to turn into cancers, experts say.

Scientists announced at the National Institutes of Health that a mutated gene responsible for an inherited killer disease called ataxia-telangiectasia, or AT, plays a key role in the internal machinery of all cells and may hold the key to basic puzzles about cancer.

A study published Friday in the journal Science said the AT gene has been isolated through a collaboration of 30 international researchers. Experts hailed the discovery as an advance that goes far beyond a single disease.

“Because a mutation in this gene affects the nervous system, also the immune system, and susceptibility to cancer, it has broad implications in advancing our understanding of the fundamental process of life,” said Zach W. Hall, director of the National Institute of Neurological Disorders and Strokes, one of the NIH agencies.

A Tel Aviv University team led by Yoshef Shiloh is credited with the actual discovery.

Shiloh said at a news conference that finding the gene offers the first real hope of treatment for AT. He said it also provides a new approach to learning how cells divide, grow, correct genetic errors and die. The AT gene is thought to be involved in each of those processes, he said.

Dr. Francis S. Collins, director of the National Center for Human Genome Research, said the discovery should help researchers find a drug or a gene therapy for AT. It also should enable development of diagnostic tests to identify people who are carriers of the mutated gene.

About 500 children in this country have AT. Worldwide, the disease strikes about one in every 40,000. About 2.5 million Americans are carriers of one copy of the AT mutation.