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Development of A Comprehensive Genetic Tool for Identification of Cannabis Sativa Samples for Forensic and Intelligence Purposes

NCJ Number
Date Published
May 2018
280 pages
This study examined the forensic genetic issues associated with the identification and origin determination of Cannabis Sativa.
A previously reported 15-loci STR multiplex was evaluated. Evaluation results indicated that this STR system is not suitable for forensic identification due to identified issues. A novel 13-loci STR multiplex was developed and optimized for cannabis sativa identification (3500 Genetic analyzer), according to ISFG and SWGDAM recommendations, using primer and multiplex STR design software, along with a gradient PCR approach for optimal annealing temperature determination. As a proof of concept, a custom panel for MPS was designed to interrogate 12 cannabis-specific STR loci by sequence rather than by size. A simple workflow was designed to integrate the custom PCR multiplex into a workflow compatible with the Ion Plus Fragment Library Kit, Ion Chef, and Ion SS system. The study resulted in a preliminary investigation of sequence variation for 12 autosomal STR loci in 16 cannabis samples. Results revealed intra=repeat variation in eight loci where the nominal or size-based allele was identical, but variances were discovered by sequence. Although the panel was not fully optimized and only a small number of samples were evaluated, this study demonstrated that more informative STR typing can be performed on a MS platform.

Date Published: May 1, 2018