The Application of DNA-Print for Identification from Forensic Biological Materials

DNA purified from more than 170 forensic samples was characterized by restriction fragment length polymorphism analysis. DNA isolated from dried blood stains, various tissues, and semen stains was digested with the restriction endonuclease Pst 1, size separated by agarose gel electrophoresis, transferred to nylon membrane and hybridized with IM probes which recognize hypervariable regions in the human genome. The size of DNA fragments, reacting to these probes, was measured with a computer assisted digitizing system and a likelihood of identity calculated from databases containing the frequency of the alleles identified with each probe. The combined discrimination potential with 4 DNA probes that hybridize to hypervariable regions is greater than 108. The present report also summarizes some of our experience in the analysis of forensic biological evidence.