Autoimmune diseases are diseases that are caused by the body’s immune cells mistaking the normal cells of the body as foreign objects and therefore attacking them. Genetic diseases are those that occur because of defective genes, specific pieces of DNA that code for a specific trait, that are passed from parent to child. Because autoimmune diseases involve the immune system, they are complex diseases that require just the right combination of defective genes along with environmental triggers for the disease to occur.
