In ALS, nerve cells or neurons waste away or die, and can no longer send messages to muscles. This eventually leads to muscle weakening, twitching, and an inability to move the arms, legs, and body. The condition slowly gets worse. When the muscles in the chest area stop working, it becomes hard or impossible to breathe on one's own. In about 10 percent of cases, the cause is genetic but in the rest, the cause is not known. We talk with a patient and a doctor about the disease and what can be done to treat it.