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Excerpt from report by Dr. David Sweet and Dr. Dean Hildebrand


"After the customary number of PCR cycles (28), there was a very weak gender profile from the second bone sample taken from the child's skull (mastoid process). Other alleles had 'dropped off,' which is usually a result of degradation of the genomic DNA. The approach when this occurs involves reamplifying the sample with 5 additional cycles in an attempt to produce a result. (The objective is to take whatever has amplified from the very tiny starting amount of DNA and subject it to further amplification--in theory the DNA doubles with each cycle so additional cycles may produce a result that can be visualized and interpreted.) Once the additional 5 cycles were performed, which is the outer limit of current technology, only one locus showed a profile: Amelogenin. The result is X-Y and this tells us two significant things. First, the child was male; second, the DNA is human."






The Starchild Skull was tested by the Bureau of Legal Dentistry (BOLD) forensic odontology laboratory at the University of British Columbia  in 1999. This lab was not designed to test for ancient DNA, but as it was not possible to access a dedicated ancient DNA lab at the time, the Project agreed to attempt the test and hope for the best. The most important difference between forensic DNA recovery and ancient DNA recovery, is that ancient samples tend to contain more contamination and less genuine DNA than a fresher sample, so they need to be treated in a specific way to remove all contamination.


BOLD tried unsuccessfully to isolate the DNA of the Starchild Skull several times, with each attempt resulting in a contamination. On the final attempt the BOLD lab reported that  they had recovered 200 picograms (the lab report states that 1,000 picograms is the normal minimum amount of genetic material required for a valid result) of genetic material from the Starchild Skull. The DNA they recovered was human nuclear DNA from the "Y" chromosome, and the lab reported that this proved the Skull to be a human male.


Due to the contamination issues, the Starchild Project felt that a second DNA test was required to verify this result. In the 2003 a second test was conducted by Trace Genetics, a specialsit ancient DNA lab. In their report on this test, Dr. Jason Eshleman and Dr. Ripan Malhi state “the inability to analyze nuclear DNA indicates that such DNA is either not present or present in sufficiently low copy number to prevent PCR analysis using methods available at the present time.”


The much more sophisticated lab equipment that was able to weed out contamination did NOT find the same DNA as the 1999 BOLD test, which indicates quite conclusively that the BOLD result was simply a contamination from one of the many people who have handled the Skull over the years, and not DNA from the actual Skull itself.


BOLD lab remains firm in their belief that their result was valid and accurate, and the Project wishes to make clear that we believe the lab performed the work to the best of their ability, and that any error was due to the inability of the equipment to adequately filter out contamination. The Project knew this was a risk when the test was comissioned, and regret any confusion caused by this result.

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