 Some patients with inherited metabolic storage disease may benefit from an allogeneic stem cell transplant allogeneic means that the stem cells come from another person. Stem cells are created in the bone marrow. They mature into different types of blood cells that are needed including red blood cells, white blood cells, and platelets. Stem cells, when transplanted, can make a new blood system. Donor stem cells can make the protein or enzyme patients with this disease cells cannot. The donor cells may prevent further accumulation of toxic substances. It is hoped that the donor cells can prevent or stop the disease from progressing. 