Cystinosis is a recessive autosomal disease that affects children in infancy. This means that both parents carry the cystinosis mutation. Often times, the parents do not show any symptoms of cystinosis. In such couples, the likelihood of either child having cystinosis is 1 in 4. Cystinosis is also called an "orphan" disease because it affects fewer than 200,000 people. It can be said to be a rare disease because of the small population and for t...