Inclusion Criteria:

Adrenoleukodystrophy: Patients from 0-55 years of age diagnosed with ALD as determined by very long chain fatty acid testing will be eligible for this protocol if they have evidence of cerebral or cerebellar disease based on MRI testing, AND they are determined high risk for any of the following reasons:

1. Age >18 years
2. MRI score >10
3. Evidence of aggressive disease that in the judgment of the Inherited Metabolic and Storage Disease group is sufficiently concerning to consider transplantation with a reduced intensity regimen instead of a standard full preparative regimen.

Metachromatic Leukodystrophy: Patients from 0-55 years of age diagnosed with MLD as determined by determinations of arylsulfatase A testing will be eligible for this protocol IF they are determined high risk for any of the following reasons:

1. Age >18 years
2. Symptomatic disease, as based on neurologic examination, or evidence of deterioration based on subsequent neuropsychologic evaluations.
3. Evidence of aggressive disease such as rapidly changing MRI determinations that in the judgment of the Inherited Metabolic and Storage Disease group is sufficiently concerning to consider transplantation with a reduced intensity regimen instead of a standard full preparative regimen.

Globoid Cell Leukodystrophy: Patients from 0-55 years of age diagnosed with GLD as determined by determinations of galactocerebrosidase testing will be eligible for this protocol IF they are determined high risk for any of the following reasons:

1. Age >18 years
2. Symptomatic disease, as based on neurologic examination, or evidence of deterioration based on subsequent neuropsychologic evaluations.
3. Evidence of aggressive disease such as rapidly changing MRI determinations that in the judgment of the Inherited Metabolic and Storage Disease group is sufficiently concerning to consider transplantation with a reduced intensity regimen instead of a standard full preparative regimen.

Patients with GM1 gangliosidosis, Tay Sachs disease, Sanfilippo syndrome or Sandhoff disease or other inherited metabolic diseases including but not limited to I-cell disease (mucolipidosis II) who are determined to be sufficiently advanced or high risk based on the following reasons:

1. Symptomatic disease, as based on neurologic examination, or evidence of deterioration based on subsequent neuropsychologic evaluations.
2. Evidence of an expected poor outcome based on genetic testing or a prior family history of aggressive disease.
3. Other metabolic disorders, including but not limited to I-cell disease, that are deemed to be high-risk for a poor outcome with a standard transplant regimen due to anticipated toxicity based on experience gained at the University of Minnesota or other centers.

Exclusion criteria:

Major organ dysfunction. Evidence of major organ impairment, including:

1. Cardiac: ejection fraction <25%
2. Renal: serum Cr >3 x normal or Cr clearance <20 mL/min.
3. Hepatic: total bilirubin >5 x normal, or ALT > 5 x normal
4. Pulmonary: requirement for respiratory support, as defined by continuous requirement for oxygen supplementation Pregnancy HIV: Evidence of HIV infection or known HIV positive serology Inability to Obtain Consent: Patients or parents are psychologically incapable of undergoing BMT with associated strict isolation or documented history of medical non-compliance. Advanced Disease Exclusion: Following evaluation, if a consensus of the members of the Inherited Metabolic and Storage Disease Program is that a patient is too advanced to benefit in a measurable and meaningful way from transplant, this will be communicated to the family, and transplant will not be offered. Measures to assist in those determinations may include: neurologic/neurocognitive functions such as activities of daily living, motor function, vision, hearing, interaction with environment, toileting, swallowing, or other standardized measures