Classical HLA genes are currently matched between patient and donor for a better outcome in allogeneic hematopoietic stem cell transplantations. Still, there are unpredictable complications with unrelated donors, because of other relevant but not yet considered gene regions within the MHC. The aim of this thesis is to evaluate the possibility of predicting the outcome of hematopoietic stem cell transplantations through haplotype matching with Conexio’s Gamma-Type™ test. This PCR-SSP indicates through comparing 25 single nucleotide polymorphisms within the HLA class III region haplotype-sequence matching. Gamma-Type™ mismatches indicate different haplotypes due to polymorphisms and recombinations. This study showed no statistical significant relevance between Gamma-Type™ matching for patient and donor and the outcome of allogeneic hematopoietic stem cell transplantations. However, Gamma-Type™ might be a helpful tool for haplotype assignment before hematopoietic stem cell transplantations.