What can you tell me about leukodystrophies?

Leukodystrophy: Metachromatic leukodystrophy (mld) is a genetic disorder that affects nerves, muscles, other organs, and behavior. It slowly gets worse over time. Mld is usually caused by the lack of an important enzyme called arylsulfatase a. Because this enzyme is missing, chemicals called sulfatides build up in and damage the nervous system, kidneys, gallbladder, and other organs. http://www.ncbi.nlm.nih.gov/p.