INCLUSION CRITERIA, RECIPIENT WITH MYELODYSPLASTIC SYNDROME (MDS)

   - Diagnosis of MDS classifiable by the World Health Organization (WHO) on the basis of:

      - Refractory anemia

      - Refractory anemia with excess blasts-1

      - Refractory anemia with excess blasts-2

      - Refractory cytopenia with multi-lineage dysplasia

      - Refractory cytopenia with multi-lineage dysplasia and ringed sideroblasts

      - Chronic myelomonocytic leukemia (CMML)

      - MDS transformed to acute leukemia

      - MDS-unclassified

   - Participants with advanced MDS must have < 10% marrow blasts prior to receiving
   conditioning with TLI/ATG, documented by marrow examination within 1 month prior.

   - Participants with evolution to acute leukemia (AML) must be in a morphologic leukemia
   free-state (MLFS) with blasts < 5%

INCLUSION CRITERIA, RECIPIENT WITH MYELOPROLIFERATIVE DISORDER (MPD)

   - Diagnosis of MPD on the basis of:

      - Idiopathic myelofibrosis

      - Polycythemia vera

      - Essential thrombocythemia

      - Chronic myelomonocytic leukemia (CML)

      - CML, Philadelphia chromosome-negative

      - Chronic neutrophilic leukemia

      - Chronic eosinophilic leukemia

      - Hypereosinophilic cyndrome

      - Systemic mastocytosis

   - < 10% marrow blasts prior to receiving conditioning with TLI/ATG, documented by marrow
   examination within 1 month prior.

   - Participants with evolution to acute leukemia (AML) must be in a morphologic leukemia
   free-state (MLFS) with blasts < 5%. Presence of residual dysplastic features following
   cytoreductive therapy is acceptable.

INCLUSION CRITERIA, RECIPIENT WITH THERAPY-RELATED MYELOID NEOPLASM (t MDS)

   - < 10% marrow blasts prior to receiving conditioning with TLI/ATG, documented by marrow
   examination within 1 month prior.

   - Morphologic leukemia free-state with blasts < 5 %.

   - Age > 50 years, or < 50 years of age but at high-risk for regimen-related toxicity
   associated with conventional myeloablative transplants due to pre-existing medical
   conditions or prior therapy

   - Availability of a fully HLA-matched or single antigen/allele mismatched sibling or
   unrelated donor

   - Prior malignancy diagnosed > 5 years ago without evidence of disease, or < 5 years ago
   with life expectancy of > 5 years are eligible (prior malignancy is not a requirement)

INCLUSION CRITERIA, DONOR

   - Donors must be HLA-matched or one allele mismatched.

   - Donor age < 75 (EXCEPTION by Principal Investigator discretion)

   - Must consent to PBSC mobilization with G-CSF; apheresis; and collection and donation
   of plasma

   - Donor must consent to placement of a central venous catheter in the event that
   peripheral venous access is limited.

EXCLUSION CRITERIA, RECIPIENT

Any of the following:

   - Uncontrolled CNS involvement with disease

   - Pregnant

   - Cardiac function: ejection fraction (EF) < 35% or uncontrolled cardiac failure

   - Diffusing capacity of the lungs for carbon monoxide (DLCO) < 40% predicted

   - Bilirubin > 3 mg/dL

   - Aspartate aminotransferase (AST) > 3x the upper limit of normal (ULN)

   - Alanine aminotransferase (ALT) > 3x ULN

   - Estimated creatinine clearance < 50 mL/min

   - Karnofsky performance score (KPS) < 70%

   - Documented fungal disease that is progressive despite treatment

   - HIV-positive

EXCLUSION CRITERIA, DONOR

Any of the following:

   - Identical twin to recipient

   - Pregnant or lactating

   - Prior malignancy within the preceding 5 years (EXCEPTION: non-melanoma skin cancers)

   - HIV seropositivity