The increasing adoption of high-density single nucleotide polymorphism (SNP) analysis in forensic genetics has expanded the scope of human identification, particularly in forensic investigative genetic genealogy (FIGG), complex missing person cases, and extended kinship analysis. Targeted hybridization capture approaches enable the recovery of large numbers of informative SNPs from highly degraded and limited DNA, such as that obtained from skeletal remains. Despite these advances, systematic evaluations of dense SNP capture panels under authentic forensic conditions remains limited. In this study, we evaluated the performance of two targeted hybridization capture panels, each targeting approximately 1.2 million forensically relevant SNPs, the myBaits Compass panel from Daicel Arbor Biosciences and a custom FIGG panel from Twist Bioscience. A set of challenging forensic samples, including skeletal remains and other degraded sample types, together with high-quality reference samples were analysed to represent both casework conditions and controlled benchmarking scenarios. DNA extraction was followed by library preparation using the EvoPrep protocol and sequencing on a NextSeq 1000 platform. Sequencing data was bioinformatically processed using CLC Genomics Workbench and final genotype calling using an in-house developed R script. Panel performance was assessed across multiple key metrics, including SNP recovery and genotype concordance. Genotype accuracy, sensitivity and reproducibility of the methods were assessed using reference samples, enabling controlled comparison of the panels. In addition, genotype calling strategies based on standard threshold-based approaches were compared with probabilistic genotyping using genotype likelihoods. Practical aspects of panel implementation, including workflow complexity, hands-on time and cost will also be presented. The findings will provide valuable insights into relative performance of these panels and support implementation of targeted SNP capture strategies in forensic casework, including both FIGG and general forensic applications.

Authors

• Adam Staadig (Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Sweden)
• Daniel Kling (Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Sweden)
• Andreas Tillmar (Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Sweden)