Even though several diseases result from mutated genes which can be passed onto children from their parents, genetic testing cannot accurately predict what diseases or conditions you definitely will develop. You could carry altered genes which may never reveal themselves, or may do so only slightly. On the other hand, your abnormal genes could reveal themselves only under certain circumstances presented by your environment. For example, if you inherit a lung cancer-related gene and you smoke, lung cancer could become a reality. If a sibling with the same abnormal gene doesn't smoke, she may not develop lung cancer, or not as early in life as you might.
Likewise, if you have an abnormal gene which is an indicator for heart disease, you may never realize it, or if you work at a high-pressure office it may contribute to your first heart attack at age 39. If your child carries an abnormal gene related to asthma, he may never have a problem until he sits at his first campfire. There is always interplay between your genetic makeup and your environment.
Gene alterations can also take place during your lifetime, resulting in disease. Children living near Chernobyl have developed cancers and other diseases as they age, and residents of areas near toxic waste-poisoned water and soil also show significantly increased levels of certain kinds of cancers and other diseases when compared to the general population.
An Internet search will reveal online lab services that will make it easy to do your personal genetic testing at home, or you can discuss your concerns with your doctor or a genetic counselor and be tested with their help.
If you plan to test on your own, it's critical to remember that:
- There are not tests available for all diseases and conditions, nor for every type of cancer.
- Test results indicating a gene mutation do not predict that you will develop the particular disease, just that your chances are higher than those without the mutation.
- Test results that show no gene mutations in your DNA do not mean that you will not develop a similar disease on your own, such as another type of breast cancer.
- Online labs that are members of the American Association of Blood Banks adhere to stringent standards, assuring you reliable results.