My cousin died of this disease at age 21. It is a genetic disorder not related to environmental issues. It is most prevalent in those of northern European descent, thus so many cases in areas of heavy immigration of northern Europeans. (Upstate New York, West Michigan, etc..) Both parents must carry the Batten's gene and even then there is only a 1 in 4 chance that the child will be affected. My best wishes to the family - it is not an easy thing for a family to endure, but there are bright spots along the way.