On one hand you'll know and be able to blame your genetics while working with your healthcare providers on any developing treatments. On the other hand, that data could potentially be used against you in the future for life insurance, disability insurance, or long term care insurance.
Seems like a damned if you do, damned if you don't type of situation. Make sure you read the privacy policies of any provider you go through. DNA is the most personal, private, and detailed part of you. Is it really worth it?