Résumé
The forensic analysis of DNA enables the identification of an individual based on molecular evidence left at the scene of the crime. The DNA polymorphisms are detected either by restriction fragment length polymorphisms [RFLPs] or by polymerase chain reaction [PCR], which allowed for detection of genetic markers in samples containing as little as 2 ng of DNA. Many studies have been conducted on the stability of DNA obtained from postmortem tissues and organs other than blood including bones and teeth. The aim of the present work was to verify the medicolegal importance of amplification of DNA extracted from human bones as a tool of identification of unidentifiable human remains. The present study was conducted on 35 bone specimens and 5 complete teeth. All specimens were at least 20 years old. DNA was extracted by the organic phenol-chloroform method. The quality and quantity of extracted DNA was assessed by running yield gels. The Quanti Blot Human Quantitation kit supplied by Perkin Elmer was used for quantitation of human DNA by hybridization of biotimiated oligonucleotide probe [D17Z1] to DNA samples immobilized to a Pall- Biodyne nylon membrane. DNA amplification was done using Perkin Elmer 480 DNA thermal cycler. Typing for the six loci [DQAI, LDLR, GYPA, HBGG, D7S8 and GC] was performed by hybridization of the amplified PCR products to the DNA probe strips. DNA was successfully extracted from 35 specimens [87.50%], and out of these samples 6 samples [17.14%] showed a significant amount of degraded DNA. DNA yields were higher in spongy bone than in compact bone. Out of 35 samples 32 [01.43%] were successfully amplified and typed for the six mentioned loci