ABSTRACT
In forensic casework, standard DNA analysis does not inform on the mode of contact or interaction causing the biological material to be transferred to from where a sample was collected, i.e., it does not allow for contextualization of the trace material and to reconstruct how it had been deposited. This context, though, may be critical to assess the actual modus of involvement of an individual in the crime in question. Consequently, the question as to how a particular biological sample came to be, or what different components it comprises, or whether it contains a certain component (e.g., a specific body fluid or tissue) is of increasing forensic interest and will often be essential to assess the evidentiary value of a given stain or trace.
This chapter provides the foundations of forensic identification of body fluids and tissues; it first introduces well-established, widely used “classical tests” for body fluid identification and then discusses in detail the advantages, principles, and methodologies of the more progressive, molecular approaches of RNA analysis and DNA methylation analysis. Subsequently, various other approaches to body fluid and tissue identification are presented, including fluorescence and mass spectrometry and microbiomics. The chapter closes with an outlook on future developments and new technologies.
