Laboratory Methods and Bioinformatics for Investigative Genetic Genealogy

Investigative Genetic Genealogy (IGG) is a powerful technique that combines DNA analysis with traditional genealogical research to narrow down the possibilities for the identity of an unknown individual. Since the arrest of the Golden State Killer in May 2018, IGG has been publicly acknowledged in 464 Unidentified Human Remains (UHR) and 318 perpetrator cases as of December 2023, and has been used in many more unacknowledged cases. Parabon alone has contributed to over 320 identifications, more than 1/3 of which have not been acknowledged publicly. A critical component of successful IGG is the quality of the genotypes generated from the forensic sample. This chapter will provide a brief overview of the IGG process, describe how data quality impacts IGG cases, and discuss various laboratory and bioinformatics techniques for generating high-quality genome-wide Single-Nucleotide Polymorphism (SNP) genotype data from challenging forensic DNA samples.