Inclusion Criteria:

-Hematologic Malignancy: High risk ALL in first complete remission ALL or ANLL in second
or subsequent remission ANLL in relapse MDS CML in any chronic phase or accelerated phase
Severe aplastic anemia refractory to medical therapy The subject is negative for CNS
disease at time of enrollment.

- Inborn errors of metabolism Hurler Syndrome (MPS I) Hurler-Scheie Syndrome Hunter
Syndrome (MPS II) Sanfilippo Syndrome (MPS III) Morquio Syndrome (MPS IV)
Maroteaux-Lamy Syndrome (MPS VI) Krabbe Disease (Globoid Leukodystrophy)
Metachromatic Leukodystrophy (MLD) Adrenoleukodystrophy(ALD and AMN) Sandhoff Disease
Tay Sachs Disease The subject does NOT have uncontrolled seizures, apnea, evidence of
aspiration pneumonia or evidence of brain stem involvement on MRI scans

- Congenital marrow failure Amegakaryocytic thrombocytopenia TAR Kostmann's Syndrome
Schwachman-Diamond Syndrome Blackfan-Diamond Anemia

- Congenital immunodeficiency syndromes requiring myeloablative therapy Wiscott
Aldrich Syndrome LAD CGD FEL/HLH CVID/CID

- SUBJECT'S DONOR Subject does NOT have a 6/6 or 5/6 antigen matched related bone
marrow donor. Suitably matched cord blood unit with adequate cell dose is available.
Unit must be in a dual compartment bag.

PERFORMANCE STATUS and ORGAN FUNCTION

- <55 years of age at time of enrollment.

- Lansky score between 60% and 100%, or a Karnofsky score between 50% and 100%

- Adequate function of other organ systems

- Creatinine < 2.0 mg/dl and creatinine clearance > 50 cc/min/m2

- Hepatic transaminases (ALT/AST) < 4 x normal, bilirubin < 2.0 mg/dl

- Normal cardiac function by echocardiogram or radionuclide scan

- Pulmonary function tests demonstrating FVC, CVC, and FEV1 of >60% of predicted for
age. For adult patients DLCO > 60% of predicted. If patient cannot perform PFTs,
clearance by the pediatric or adult pulmonologist will be required

- No uncontrolled infections at the time of cytoreduction

- NOT pregnant or lactating (must have a current negative pregnancy test)

- HIV negative

- Subject is not concurrently involved in any other clinical trial that affects
engraftment or immune reconstitution (e.g. other hematopoietic growth factors).

- Subject does not have any co-morbid condition, which in the view of the Principal
Investigators, renders the patient at too high a risk from treatment complications
and regimen related morbidity/mortality.