DIRECT EVIDENCE OF ANCIENT DNA FROM HUMAN BONES UP TO TWELVE THOUSAND YEARS OLD BY PROBE HYBRIDIZATION

Efforts from many research groups, often in a hunt for the oldest sequences, showed that ancient DNA was a poor substrate for the enzymes used in molecular biology, present in tiny amounts, hard to purify, copurifying with inhibitors of polymerase chain reaction (PCR) and frequently damaged. Inside ancient DNA extracts, the quantity of the DNA of interest and its genuine specie, have never been evaluated before, but with quantitative PCR. Herein, direct DNA quantitation method was applied. This method should be a useful tool for ancient DNA study as it is currently for forensic material. Among techniques performed on forensic samples, we chose a chemiluminescent method based on probe hybridisation to a human alpha satellite locus D17Z1. We thought that such a rapid and sensitive method, might be extended to the ancient human DNA applications, especially as the study of nuclear ancient DNA is growing up. We report now the successful quantitation of nuclear human DNA in DNA extracts prepared from very ancient bones. Twenty-four different human specimens, up to 12,000 years old, were analysed and the quantity of human DNA content determined for fourteen DNA extracts on twenty-nine tested.