You actually raised a very interesting point. This is a difficult ethical issue we have to deal with in real practice. You are right. For some genetic diseases such as cancer, we can offer patients prophylactic strategies if they are positive for a deleterious mutation.But this approach is not applicable to every genetic disorders. Huntington is undoubtedly a good example. As you said, there is no cure for Huntington. So if a patient has family history of Huntingtin, he/she would have about 50% chance to inherited the mutation. In this case, testing or not is a question. It all depends on how much information the patient wants to learn and what the patient will do based on the test result. Some might want to know if they carry the mutation so that they can prepare their life or find peace in mind if they are tested negative. Some might be unable to bear the anxiety provoked by testing itself as well as positive results and choose not to be tested. It is absolutely personal choice. Genetic testing and counseling are for benefiting patients and their families. We dont want to exaggerate their emotional burden. Neither testing nore counseling is mandatory, but options for patients to consider.There are some guidelines for testing, especially testing minors (people younger than 18 years old). Usually we don't test children before they can make their own decisions about testin or not.
One big benefit as far as I am concerned is to benefit next generation. Take Huntington as an example. If one of parents are at increased risk of having Huntington due to family history, but don't want their children to be affected, they can request testing the embryo and only keeping the unaffect. Therefore, their children would be free of Huntington. Meanwhile, we won't have to disclose the parent's carrier status. This procedure is called preimplantation genetic diagnosis, which can be used for many incurable diseases including some cancers.
Very glad talking to you about genetic testing here. The pleasure is all mine.
