A paper published in this week's Journal of Clinical Oncology says Transforming Growth Factor Beta Receptor 1*6A (TGFBR1*6A) - a mutated gene present in nearly one in eight people and the most commonly inherited cancer susceptibility gene identified so far - might be responsible for a significant proportion of familial colorectal cancers.
The study, published by researchers at Northwestern Memorial Hospital and Northwestern University's Robert H. Lurie Comprehensive Cancer Center, says 15 to 20 percent of all colorectal cancers are familial, but only 7-8 percent are caused by mutations of known colorectal cancer genes such as the APC, MLH1, MSH2 and MSH6 genes.
In an earlier study, Dr. Pasche and his colleagues had found that TGFBR1*6A may increase the risk for all colon cancers by 20 percent. "There is growing evidence that TGFBR1*6A is associated with an increased risk of colorectal cancer but its specific contribution to familial colorectal cancer was unknown," explained Dr. Pasche. Now, Dr. Pasche believes the gene is especially potent as a cause for familial colon cancers.