In the present pilot study we applied recently published protocols for detecting Mycobacterium tuberculosis in human remains. We screened long bones from an 18th century cemetery and skulls from the anatomical "Weisbach collection" (19th century). In addition, besides the study of abundance of tuberculosis in inmates of the poorhouse itself, we were interested to test whether in this particular instance tuberculosis can be identified from cortical bones, which are rarely affected by tuberculosis, but mostly better preserved than the vertebral bodies or epiphyses.
Method: The DNA extractions from the bone samples were obtained following established ancient DNA protocols. Subsequently extracts were subjected to a series of PCR amplifications using primer pairs published previously 12. PCR products of the expected size were subsequently sequenced.
Results: Only primers targeting the repetitive IS6110 insertion sequence yielded PCR products of appropriate size. In one sample only (skull sample WB354 of the "Weisbach collection") sequence analysis revealed an authentic M. tuberculosis sequence that matched to a reference sequence from GenBank.
Conclusion: With a variety of established PCR approaches we failed to detect M. tuberculosis DNA in historic human femurs from an 18th century cemetery relating to a poor house in Kaiserebersdorf, Austria. Our data may indicate that in this particular case, thoracic or lumbar vertebrae, i.e. bones that are severely affected by the disease, would be more suitable for molecular diagnostics than long bones. However, the unpredictable state of DNA preservation in bones from museum collections does not allow any general recommendation of any type of bone.