Assessment of QIAGEN™ Investigator® 24plex GO! kit workflow for autosomal STR profiling of forensic reference samples

Abstract

Background: DNA profiling has proven to be a valuable technique for identification of individuals in crime. Currently, the technique targets several short tandem repeat (STR) regions in human genome. However, increasing number of samples submitted for STR analysis may lead to delays due to the limited number of experienced analysts who might be available at any given moment and the time taken to complete lengthy DNA profiling procedures. This study was conducted to test the specificity, repeatability, reproducibility and robustness of Investigator® 24plex GO! kit for genotyping of reference samples submitted to the Royal Malaysian Police Forensic DNA Laboratory for DNA database. Material and methods: In this study, Investigator® 24plex GO! kit was used to directly amplify STR loci from buccal swab cell of reference samples that had previously been STR typed using GlobalFiler™ Express kit. Capillary electrophoresis was carried out on a 3500xL Genetic Analyser using POP-4® Polymer. Amplified products were assigned to particular STR alleles using the GeneMapper ID-X version 1.4 software. Results: Our study shows that STR profiles generated using Investigator® 24plex GO! gave concordance results with those previously obtained using the GlobalFiler™ Express kit. In addition, quality sensors included in the kit are of particular importance for determining the effectiveness of the PCR reaction and help to indicate the nature and quantity of DNA template for PCR amplification. Conclusion: The Investigator® 24plex GO! kit is reliable for STR typing of reference samples.