The effect of blood transfusion on DNA profiles of an individual is a significant issue in the forensic context. In the present study, the effects of blood transfusion in 5 recipients were studied by performing restriction fragment length polymorphism and polymerase chain reaction HLA-DQA1 and Polymarker (LDLR, GYPA, HBGG, D7S8, and GC) assays (Roche Molecular Systems, Branchburg, NJ) on serial posttransfusion blood samples. Pretransfusion and posttransfusion DNA profiles of all 5 recipients were consistent with no evidence of the donor genetic material. Currently used DNA profiling techniques in forensic science are reliable and informative for paternity and identity purposes in situations involving transfusion of 1 or 2 U of blood up to 24 hours posttransfusion.