Genetic testing is performed on the genetic material - the DNA - found in blood taken from a simple blood test. Sometimes the test also involves a pathology sample of a tumor. The genetic material is saved for future tests at the family's request.
It is preferable to perform the test using a sample from a person who is sick in order to identify the genetic change that exists in the family. If a change is identified in the test performed on the sick family member then it is recommended that the test be performed on health family members.
Testing for common changes in certain population groups, or changes that characterize a particular family, are relatively simple to perform and in most cases are funded by the Public Health Clinics and/or supplementary insurance coverage.
If no changes are found in this test, or if common changes are not found and a hereditary condition is suspected, we will recommend a full scan of the suspicious genes or other complex genetic tests. These tests are often complicated and expensive and therefore we recommend that they be carried out only in cases where a genetic-hereditary condition is greatly suspected.
In cases where a cancer gene is very likely, tests were carried out but a genetic component was not identified, this does not rule out its existence. This could be a case of a gene that hasn't yet been identified. In these cases the family is referred for monitoring for early identification and prevention, in accordance with the level of risk determined on the basis of the family history.