Biogeographical Ancestry Estimation from Autosomal Short Tandem Repeats in the Sequencing Era

Le résumé fourni par la source

Autosomal short tandem repeats (STRs) are, and likely always will be, the first loci targeted for forensic DNA analysis as they offer the highest probability of individual identification. An ancestry-informative marker panel can then be used in “no hit, no suspect” cases, which requires additional time and cost investment, and relies on the presence of sufficient remaining sample. Traditionally this has relied on the use of specific ancestry-informative single nucleotide polymorphisms (SNPs), run as an additional test to STRs. STRs have largely been discounted for biogeographic ancestry determination due to their high mutation rate, which in turn makes them well suited for individual identification. Being able to obtain a DNA profile that can simultaneously be used both for biogeographical ancestry estimation and searching against offender databases would be of huge benefit to the field of forensic identification in terms of time, cost, and sample availability. As routine DNA testing of autosomal STRs progresses to next-generation/massively parallel sequencing, the opportunity presents itself to make use of observed sequence diversity in new ways. In particular, the presence of population-specific sequence variation raises the prospect of using STR profiles for population identification, both on their own and in combination with ancestry-informative SNPs. In this study, data were extracted from 989 samples from five global population groups prepared and sequenced using the ForenSeq DNA Signature Prep kit and the MiSeq FGx. Good differentiation between population was achieved using sequenced STR profiles, with 84% of samples classifying correctly using a conservative classification approach, and a general error rate of 3.5%—results that also showed a clear improvement over length-based data.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.