Saliva protein profiling for subject identification and potential medical applications

This study delineates a protocol to obtain a set of proteins from human saliva to distinguish objectively among individual donors. A small subset of proteins (<10%) of those identified by mass spectrometry from wet saliva samples allowed to discriminate among donors supporting the notion that most of the salivary proteome is highly conserved across subjects. Most of these discriminating proteins were involved with immunity, tissue metabolism and regeneration. They were already identified in other saliva proteome studies including those performed with dry saliva samples indicating the likelihood of using wet or dry saliva samples. The differences in the proteomes across subjects likely reflect a combination of different lifestyle habits, environmental factors, underlying diseases/conditions, among others, but not necessarily age. Application of such proteomic analysis has the potential to increase substantially the value of saliva as a source of proteins in forensic evidence.