I-Familia: Identifying Missing Persons Globally through Family DNA Kinship Matching

The identification of human remains belonging to missing persons is one of the main challenges for forensic genetics. Although other means of identification can be applied to missing person investigations, DNA is often extremely valuable to further support or refute potential associations. When reference DNA samples cannot be collected from personal items belonging to a missing person, a direct DNA identification cannot be carried out. However, identifications can be made indirectly using DNA from the missing person’s relatives. The ranking of likelihood ratio (LR) values, which measure the fit of a missing person for any given pedigree, is often the first step in selecting candidates in a DNA database. Although implementing DNA kinship matching in a national environment is feasible, many challenges need to be resolved before applying this method to an international configuration. In June 2021, the International Criminal Police Organization INTERPOL launched I-Familia, a new DNA database aiming to facilitate the identification of missing persons globally through family DNA kinship matching. This straightforward method, based on calculations performed with the DNA matching software BONAPARTE, Worldwide allele frequencies and tailored cutoff log₁₀LR thresholds, allows for the classification of potential candidates according to the strength of the DNA evidence and the predicted proportion of adventitious matches¹. This is a powerful method for streamlining the decision-making process in missing person investigations and DVI processes, especially when there are low numbers of overlapping typed STRs. Intuitive interpretation tables and decision trees help strengthen international data comparison for the identification of reported missing individuals discovered outside their national borders, ultimately bringing closure to many families.

¹ Laurent, F.X., Fischer, A., Oldt, R.F., Kanthaswamy, S., Buckleton, J.S., and Hitchin, S.(2022) Streamlining the decision-making process for international DNA kinship matching using Worldwide allele frequencies and tailored cutoff log10LR thresholds. Forensic Sci Int Genet. 57:102634. doi:https://doi.org/10.1016/j.fsigen.2021.102634