A researcher named D.M. Eccles wrote an article about developments in genetic testing for Breast, Ovarian and Colorectal Cancer Predisposition in an effort to illustrate how this new testing could aid doctors in finding cancerous cells early in development or prevent them before they even develop.

Eccles started by explaining over years of prior research into where cancer comes from he explained that it had been discovered that in the 1980’s the first high risk cancer susceptibility genes were (FAP) Familial Adenomatous Polyposis which is when numerous polyps form in the epithelium of large intestine which can develop into colon cancer if not treated. Then along in 1993 there arose a condition known Lynch Syndrome which is known as an autosomal dominant (expression of non sex genes) genetic condition that has risk for ovarian, colon, and some skin cancers. Then the following year in 94’ in the BRCA 1 and BRCA 2 genes researchers found the location and sequences of both these caretaker genes are found in the breast and that stabilize genomes and repair DNA. If these are damaged then they aren’t able to fix DNA and can’t be fixed themselves which comes to yield cancerous results such as breast and ovarian. So after finding out these things researchers have started using genetic testing in a clinical aspect to figure what genes are forcing which types of cancers to occur. For example, if there was gene mutation in the BRCA1 and BRCA 2 proteins in someone’s family and all those affected were deceased and researchers tested someone from the family who was unaffected but at risk may reassure that fact that this mutation brought about ovarian cancer. But in actuality after testing the cancer could’ve come from a mutation in the RAD51C and RAD51D genes. These are a set of genes that are responsible at a high risk for ovarian cancer and possibly breast cancer if the genes happened to be mutated. So all the reason for the genetic testing is to distinguish between these and figure out with of these genes can be targeted as the one developing into becoming cancerous.

The specifics of how to figure out which genes to target for cancer prevention where narrowed more as Eccles discussed gene expressivity and penetrance. Not all people who carry the gene that makes predisposed to cancer will ever develop it which is known as incomplete penetrance. So in a family that may contain a mutation can have predictive genetic testing done to identify if the high risk gene. People who have (FAP) with polyps that are benign and may be on the verge of them becoming carcinogenic usually have mutation genetic testing which will identify where the causative mutation is in the gene. If that is discovered then a predictive test can be done on any member of the same family to have target surveillance on all the gene carriers. So even though colonoscopies, self-breast examinations, and oophorectomy are classics in detecting colon, breast, and ovarian cancer researchers are trying to push these new methods in genetic testing to catch these cancers fairly early on.

James