OBJECTIVES: I. Determine whether the use of donors with a one non crossreactive group (CREG) mismatch for HLA-A or B in patients less than 36 years of age is associated with more frequent graft versus host disease (GVHD) of grades III-IV than previously observed with donors with one CREG mismatch. II. Determine whether the use of donors with a one CREG mismatch for HLA-A or B in patients 36-50 years of age is associated with more frequent GVHD of grades III-IV than previously observed with matched donors. III. Determine the relevance of HLA-A allele mismatching in bone marrow transplants from donors matched for HLA-A, B, and DR phenotypes.