Exploring the Potential of Genome-Wide Hybridization Capture Enrichment for Forensic DNA Profiling of Degraded Bones

In many human rights and criminal contexts, skeletal remains are often the only available samples, and they present a significant challenge for forensic DNA profiling due to DNA degradation. Ancient DNA methods, particularly capture hybridization enrichment, have been proposed for dealing with severely degraded bones, given their capacity to yield results in ancient remains.

This paper aims to test the efficacy of genome-wide capture enrichment on degraded forensic human remains compared to autosomal STRs analysis.

Six highly degraded human bones from the Spanish Civil War (1936-1939) were quantified with Quantifiler^™ Trio and amplified with GlobalFiler^™. Independently, partially UDG-treated double-stranded DNA libraries were generated and shotgun sequenced to screen for endogenous human DNA content. Subsequently, libraries were enriched with the Twist Bioscience "Twist Ancient DNA" reagent enrichment kit, which had not been previously tested for forensic purposes.

The results show that the samples behave similarly with both approaches (well-preserved samples yield good results). However, capture enrichment provides some new relevant insights, suggesting that its implementation in current NGS forensic platforms could be beneficial.

Shotgun results show that the analyzed samples exhibit the same characteristics as ancient DNA samples in terms of DNA fragmentation and molecular damage, which may enhance the value of this approach when authenticating the endogenous DNA of forensic samples.