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On-Site Confirmatory Test for Tissue Type and Specimen Age

NCJ Number
Date Published
July 2014
35 pages
This report presents the findings and methodology of a research project with the goal of developing a relatively inexpensive, rapid means of identifying body-fluid type and determining whether the sample is of human origin.
The project confirmed that tissue-specific RNAs can be targeted to determine the biological nature of a stain without the use of PCR. The technique has a short assay time, in which multiple samples can be processed in less than 1 hour. Knowing whether a stain at a crime scene is biological, along with determination of the exact tissue type while at the crime scene can assist in reducing the number of items collected by crime-scene technicians. This method, once optimized in multiplex, may also assist in reducing the prevalent backlogs of evidence awaiting analysis by crime laboratories. To make this approach portable, the following requirements must be met: a small fluorospectrometer, small centrifuge, a stable surface for the centrifuge and fluorospectrometer, a laptop, a power source for the centrifuge, a means to isolate the samples, pipette, and reagents maintained at room temperature. Once optimized in a multiplex reaction, further experimentation will be required to determine limitations of the MB technique due to the age or degraded state of a sample. It is also necessary to determine the smallest volume of biological fluid required for proper confirmation of presence in a multiplexed assay. 7 figures, 5 tables, and 29 references

Date Published: July 1, 2014