DISEASE CHARACTERISTICS:

• Nonmalignant disease treatable by allogeneic hematopoietic stem cell transplant (HSCT)
• Patients with preexisting medical conditions or other factors that renders them at high risk for regimen-related toxicity or ineligible for a conventional myeloablative HSCT
• No aplastic anemia or Fanconi anemia
• No patients with metabolic storage diseases who have severe CNS involvement of disease, defined as IQ score < 70

• Suitable related or unrelated donor available, meeting the following criteria:

  • Related donor who is HLA genotypically identical at least at one haplotype and may be genotypically or phenotypically identical for serological typing for HLA-A, -B, -C, and at the allele level for -DRB1 and -DQB1

    • Related donors must be a match or a single allele mismatch at HLA-A, -B, and -C (at highest resolution available at the time of donor selection) and matched at -DRB1 and -DQB1 by DNA typing
    • Must not be an identical twin

  • Unrelated donor who is matched at HLA-A, -B, -C, -DRB1 and -DQB1 by DNA typing at the highest resolution routinely available at the time of donor selection

    • Only a single allele disparity will be allowed for HLA-A, -B, or -C as defined by high resolution typing
    • No mismatching for -DRB1 or -DQB1 is allowed

PATIENT CHARACTERISTICS:

• Cardiac ejection fraction ≥ 30% on MUGA scan or cardiac ECHO
• No symptomatic coronary artery disease
• No other cardiac failure requiring therapy
• No poorly controlled hypertension despite anti-hypertensive medications

• No hepatic conditions for patients with clinical or laboratory evidence of liver disease in terms of liver function and the degree of portal hypertension, including the following:

  • Fulminant liver failure
  • Cirrhosis of the liver with evidence of portal hypertension
  • Bridging fibrosis
  • Alcoholic hepatitis
  • Esophageal varices
  • History of bleeding esophageal varices
  • Hepatic encephalopathy
  • Uncorrectable hepatic synthetic dysfunction evidenced by prolongation of the prothrombin time
  • Ascites related to portal hypertension
  • Bacterial or fungal liver abscess
  • Biliary obstruction
  • Chronic viral hepatitis with total serum bilirubin > 3 mg/dL
  • Symptomatic biliary disease
• No seropositivity for human immunodeficiency virus (HIV)
• Not pregnant or breast-feeding
• Negative pregnancy test
• Fertile men or women must use contraceptives during HSCT and up to 12 months post-treatment
• Patients with fungal pneumonia with radiological progression after receipt of amphotericin formulation or mold-active azoles for greater than 1 month are not eligible

PRIOR CONCURRENT THERAPY:

• Not specified