Amyotrophic lateral sclerosis (ALS), commonly known as Lou Gehrig's disease, is not contagious. It is a genetic disease associated with autosomal dominant inheritance and is not considered an infectious disease. The exact cause of ALS is still unclear. Commonly identified mechanisms include genetic factors, inflammatory agents, excitotoxic effects from amino acids, infections, autoimmune factors, exposure to toxins, and heavy metal poisoning from metals like lead, mercury, and aluminum. Other contributing factors may include a deficiency in nerve growth factors, mitochondrial dysfunction, and apoptosis. These factors may likely be involved in the development of ALS symptoms, but the disease is not communicable.