What are the ethical and legal issues involved with gene testing?

Gene testing is a double-edged sword in terms of what will be done with the information gathered. One side of the argument is, if you were tested, would you want to know that you have an untreatable, incurable disorder that the current medical field is unable to deal with? Would you want your employer or health insurance provider to be aware of a situation like this? On the other side of the argument, wouldn't you want to know so that you and your family could plan ahead? Also, if you have a treatable disorder, would you want to know as soon as possible to prevent further pain and suffering? How would an insurance company react to this information, especially if the treatment is expensive? Many current treatments and therapies are rejected by these companies as it is. How can society deal with this situation and still allow people the right to know what disorder they've inherited? What about the mental anguish associated with the knowledge of a life-threatening genetic disorder?