A bone marrow transplant (BMT), replaces an affected person's bone marrow with donor marrow that can produce the missing enzyme. The procedure is risky, invasive and has had very little success in Tay-Sachs, Sandhoff and GM-1. If done early enough it can be effective in slowing and even stopping the disease in other allied diseases like Krabbe and MPS.Bone Marrow Transplant is very invasive. Children often succumb to complications of the procedure. The immune system must be completely destroyed before introducing the healthy bone marrow. It is unclear how many of the healthy stem cells cross into the central nervous system.