IDENTIFICATION OF ARCHAEOLOGICAL BLOOD PROTEINS - A CAUTIONARY NOTE

Submission of archaeological specimens for blood residue analysis is being promoted increasingly as a necessary step in the routine study of ancient remains and artefact assemblages. The validity and usefulness of this practice, however, are unknown, and the accuracy and comparability of the different laboratory tests employed have never been examined adequately. The most promising methods for detecting blood proteins and determining species of origin are based on recognized standard medical and forensic procedures. Application of these various techniques to archaeological residues, however, remains experimental. Independent investigators, using different approaches, have been reporting successful identifications of prehistoric proteins with increasing frequency and confidence. Despite perceived internal consistency and accuracy of each analytic technique, external consistency and comparability of reported results have not been demonstrated. A central question relates to blood protein survival over time and the relative capability of the different laboratory methods to detect, identify and discriminate accurately between the ancient degraded proteins. The purpose of this paper is to address some of these issues, and to sensitize both researchers and archaeologists to the need for caution in reporting and interpreting unconfirmed test results on ancient blood proteins.