This is a scary situation but if you do have it. The sooner they catch it the easier its going to be on you if you do have it. They can slow down the process at least. My uncle has a rare case of huntingtons and he will adventually die from it but he has had sense he has been born. They have been slowing down the process as much as possible. He is now 47 years old and still kicking. Its not a fun diesase but at least you can live a long life. If you get tested and you don't have it, then you just got some releaf in life knowing you don't have it. My uncle doesn't have kids. My mom doesn't have huntingtons and either does me or my sister. We are all grown adults. Get yourself checked out because you may not even have it. Also depression is caused by all kind of things like it could be genetic or it could be events in your life that caused you to get depressed. Yeah some dieases can cause you to have depression too but it can be as simple as the fact you where born with a chemical imbalnce. I wish you the best of luck!!!