For decades, scientists have noticed that colon cancer tends to run in families. But it wasn't clear why. Is the disease the result of a shared environment in these cases--which account for about 10% of all colon cancers? Or are nefarious genes at work? The question prompted an international team of researchers, led by Bert Vogelstein at Johns Hopkins University and Albert de la Chapelle of the University of Helsinki, to spend the last four years painstakingly searching for a genetic cause--without knowing whether it really existed. "It was very frustrating," recalls Vogelstein. "We wondered if we were wasting our time."
But now, the researchers have found the gene. While they have yet to pinpoint the exact mutation, they do know that it appears to be present in about 1 in every 200 people, making colon cancer the most common inherited disease. What's more, as they report in the May 7 issue of Science, the gene exerts its effect in a novel way. When flawed, it leads to damage in other pieces of DNA, particularly in those genes that have already been linked to rarer forms of inherited colon cancers. The scientists expect the discovery to lead to a diagnostic test within six months--and eventually result in better therapies.