A Ge.F.I. - ISFG European collaborative study on DNA identification of Cannabis sativa samples using a 13-locus...

Area of Science:

• Forensic Science
• Genetics
• Botany

Background:

• Cannabis sativa is a widely used controlled substance in Europe.
• Recent legislative changes have led to an increase in indoor cannabis cultivation.
• Internet availability of cannabis seeds facilitates the growth of these crops.

Purpose of the Study:

• To assess the reproducibility, reliability, and robustness of a 13-locus multiplex STR method for cannabis DNA profiling.
• To evaluate the practical application of this method in a forensic context across multiple European laboratories.
• To validate a standardized genetic identification technique for cannabis seizures.

Main Methods:

• A collaborative exercise involving 21 laboratories from three European countries.
• Participants performed STR typing on two cannabis samples using a provided 13-locus multiplex STR kit.
• Diverse PCR amplification, capillary electrophoresis (CE), and genotyping software platforms were utilized by participating labs.

Main Results:

• High concordance in results was achieved despite variations in equipment and software.
• An overall genotyping success rate of 96% was reported.
• Minor artifacts were observed, with low stutter percentages and manageable peak imbalances, demonstrating the system's robustness.

Conclusions:

• The 13-locus STR system is robust and applicable for cannabis DNA profiling in forensic investigations.
• The collaborative exercise confirmed the reliability and reproducibility of the method across different laboratories and platforms.
• This genetic identification technique can effectively link cannabis seizures, aiding law enforcement.