ABSTRACT
One of the earliest genes to be discovered was a hereditary defect popularly dubbed the colon cancer gene. A person possessing such a defective gene has a strong likelihood of developing a common form of cancer of the colon (large intestine), as well as an enhanced risk of other forms of cancer (Figure 2.1). Even in the absence of a family history of this disease, this person is at risk. Since the first discovery, a variety of such hereditary factors have been identified. Researchers have estimated that up to 85% of those persons carrying some types of colon cancer gene will eventually contract the disease. However, many people who will contract colon cancer have no detectable genetic defects – and even those who do carry the gene have no way of knowing who will be in the unlucky 85%. Genetic testing can put you on alert, but not detect or cure colon cancer.
