The finding has scientists re-examining commonly held beliefs about the nature and frequency of genetic mutation as a cause of cancer. Familial cancer, in contrast to inherited cancer, is defined as multiple cases of cancer in one family that cannot be accounted for by classic rules of inheritance.
The findings are published in the April 21 issue of the New England Journal of Medicine.
"The findings suggest that a lot of cancer we once thought of as random may not be so random after all," says George Calin, an adjunct assistant professor and research scientist in molecular virology, immunology and medical genetics and the first author of the study. He added that the findings hold important diagnostic and economic implications, as well.
Most geneticists believe that less than 5 percent of cancer is inherited, primarily through mutation in a relatively small number of well-known genes. Calin says that this new gene, however, dubbed ARLTS1, (ADP Ribosylation Factor-Like Tumor Suppressor 1) can also increase a person's chances of developing cancer, but only a little.
"ARLTS1 is one of an emerging set of genes whose effects are subtle, but which still play an important and predictable role in the development of cancer in some people."
Researchers have known for years that a handful of well-known genes (like BRCA1 and BRCA2, for example) can, when mutated, dramatically increase a person's risk of developing cancer. This "second tier" of genes, on the other hand, may heighten the risk of cancer for a much larger group of patients, says Carlo Croce, director of the Human Cancer Genetics Program at Ohio State and senior author of the study.