Down Syndrome is caused by a part or all third copy of chromosome 21. They tend to be sociable, affectionate, and have less capacity to be inhibited. Down syndrome is not treatable because you are born with it.
Lung Disease is caused when someone inhales deadly gases into there lungs. A persons lungs start getting infected from the deadly gases and then collapses. It is curable a people have to do is cut down on pollution.
Liver Failure is caused when someone drinks to much liquor and gets drunk. It causes health problems within the heart and can cause you to die if serious enough. It is crable by people not drinking and getting drunk.