Great question and postings! According to genomic medicine, the enzyme genetic polymorphism for breat cancer (BRCA1 and BRCA2) can be identified through testing, but it does not mean a woman will develop breat cancer. There are metabolic expressions of genes that can be influenced by lifestyle changes and nutrional and supplemental choices.
With that said, the labs who run genetic testing should abide by the same patient privacy laws (HIPAA for example)and I doubt the results are shared with insurance companies if done in privacy. I do not even know if insurance plans cover for this type of testing, so why should they claim "ownership" over the information provided by the results?
Physicians can also refuse to share medical information with payors to protect patient privacy at the request of a patient. But, here is the big BUT...from an ethical perspective, the insurance industry can argue that genetic information is theirs when they pay for the test. I anticipate a slippery slope potential....patient privacy advocacy groups need to start addressing this potential conflict sooner than later.
There is a great new book that I just finished reading written by Pamela McDonald: "The APO E Gene Diet" Pamela's website is: http://www.apoegenediet.com/testing-options2.htm
You can find more information on her site to help you decide whether to get genetic testing or not. She also suggests reading her book first and then deciding. The above link offers options including getting tested anonymously to protect your privacy from the insurance threat.