Scientists continued to chip away at the roots of cancer with the discovery yesterday of a gene linked to prostate cancer, which may increase survival rates through earlier detection.
Researchers from the University of Michigan Medical Center, the Johns Hopkins University and the National Center for Human Genome Research (NCHGR) collaborated with Swedish scientists to discover the location of a gene that causes men to be susceptible to prostate cancer.
"We collected a large number of families, each of whom had a history of cases of prostate cancer," said Dr. Jeffrey Smith, the chief author of the study and a research fellow in the University's department of internal medicine. "The goal was to identify a common genetic cause."
Researchers from the NCHGR and the Johns Hopkins University announced the findings yesterday afternoon in Washington, D.C.
While the precise location of the discovered gene has yet to be found, the researchers have pinpointed it to chromosome 1 - a chromosome not previously linked with other diseases, said Dr. Kathleen Cooney, director of the University Prostate Cancer Genetics Project.
"The hope would be to find the exact location of the gene," Smith said. "Beyond that, we'll be able to design tests that may benefit the men in these types of families. The tests would be able to tell if the man is or is not at risk and determine the best treatment."
Cooney said that if prostate cancer is detected through proper screening tests, it is not difficult to treat.
"Prostate cancer is treatable and curable if detected early, but when it's late in progress, it is not curable," she said.
Researchers spent two years tracing the genomes of 90 families from Sweden and the United States. They looked for first-degree relations - brothers and fathers - who developed prostrate cancer at a young age. Among the families studied, one third were linked with a defective gene in chromosome 1.
Smith said about 9 percent of prostrate cancer cases are estimated to be genetic.
"With a disease like prostate cancer there is bound to be heterogeneous causes," Smith said. "We tracked entire genomes within each of the families to find an inheritance of predisposition to develop the disease."
Cooney said there were doubts among scientists about the possibility of discovering such a gene.
"People thought it would be difficult to find a gene because of the late onset and sporadic cases of the disease - this task was more daunting than finding genes in other historical disorders."
Prostate cancer, which befalls one in 10 men, is the most common male cancer. More than 40,000 die each year.
"The main implication of this discovery is that the gene will likely be cloned in the next year or two to discover its biological function," said Dr. Jill Macoski, assistant professor of surgery. "Then we'll be able to tell how the lack of that function will turn a normal cell into a malignant cell, which will give insight into how cancer happens."
Cooney said the discovery is a reminder of the need for even greater family involvement.
"The finding suggests that there will be other genes involved and that we need to continue to have families involved in the research," she said.
The Prostate Cancer Project is looking for families with two or more living members with prostate cancer. Families who fit the description should call the project at 936-2031 or the University Cancer AnswerLine at (800)-865-1125.
The finding are published in today's issue of the journal Science.