Acute myeloid leukemia is a clonal haemopoietic disorder frequentlyassociated with genetic instability. Polymorphisms in DNA repairenzymes are thought to increase the risk of development of AML. Inour study we investigated 40 cases of AML and 37 controls for thepolymorphism in DNA homologous recombination repair gene-RAD51by PCR-RFLP. We found, among the cases there were 19 cases withpositive expression of the polymorphic gene, while in controls wefound only 7 candidates with positive expression of the samepolymorphism. These results suggest a strong correlation betweenthe presence of polymorphic RAD51-G135C allele and the incidenceof AML.