PURPOSE: Natural Killer (NK) cells from the donor's bone marrow may be important in fighting leukemia. Bone marrow donors can be selected based on the type of NK cells they have, specifically the killer immunoglobulin receptor (KIR) type. This study provides information on KIR type from potential donors, which can be used in selecting the bone marrow donor. This phase II trial of unrelated donor stem cell transplant in patients with high risk AML (monosomy 7, -5/5q-, high FLT3-ITD AR, or refractory or relapsed AML) in which KIR typing of the patients and potential donors will be available to the treating transplant physician at the time of donor selection.