Forensic investigative genetic genealogy (IGG) relies on SNP profiles, which are often generated using microarray genotyping or whole genome sequencing. Kintelligence™ was developed as an alternative SNP typing solution specifically designed for forensic laboratories, offering a workflow that can be readily implemented in-house and that performs well with limited or degraded DNA samples. While this approach provides clear operational advantages, it generates a substantially smaller SNP dataset compared to other methods (10,230 vs. ≈600,000 SNPs). This reduced marker density results in lower discriminatory power and increases the likelihood of false associations when Kintelligence profiles are compared to genealogy database profiles.

In this study, we characterized the false associations that occur when Kintelligence profiles are uploaded to GEDmatch PRO. We assessed the number and proportion of false associations across the platform’s tiered matching system used for Kintelligence profiles, which consists of three categories with decreasing stringency: high-confidence matches, expanded matches, and all matches. In addition, we analyzed the variation observed in the estimated total shared DNA and the estimated length of the longest shared segment. Our findings reveal distinct patterns of false associations across match categories and highlight considerations for the effective use of Kintelligence-based IGG results.

Finally, we present our strategy for conducting IGG casework, including assembling an effective multidisciplinary IGG team, selecting the most appropriate SNP technology for each case and preparing standardized IGG reports.

Authors

• Sarah Noël (Laboratoire de sciences judiciaires et de médecine légale, Canada)
• Marie-Ève Monchamp (Laboratoire de sciences judiciaires et de médecine légale, Canada)
• Tommy Harding (Laboratoire de sciences judiciaires et de médecine légale, Canada)
• Thibault de Malliard (Laboratoire de sciences judiciaires et de médecine légale, Canada)
• Audrée Gareau-Léonard (Laboratoire de sciences judiciaires et de médecine légale, Canada)
• Melissa Murillo-Radtke (Laboratoire de sciences judiciaires et de médecine légale, Canada)
• Josée Noël (Laboratoire de sciences judiciaires et de médecine légale, Canada)
• Diane Séguin (Laboratoire de sciences judiciaires et de médecine légale, Canada)