Dense SNP-based analyses complement forensic anthropology biogeographical ancestry assessments.

Area of Science:

• Forensic Anthropology
• Genomic Ancestry
• Human Identification

Background:

• Accurate ancestry estimation is vital for identifying unidentified human remains (UHRs).
• Traditional forensic anthropology methods have limitations in precision, particularly with partial remains and admixed individuals.
• The performance of anthropological ancestry estimation has not been extensively studied at scale.

Purpose of the Study:

• To compare the accuracy of anthropological ancestry estimation with genome-wide SNP analysis for UHRs.
• To quantify the extent of misattribution in anthropological ancestry assessments.
• To highlight the need for integrating genomic methods into UHR investigations.

Main Methods:

• Analysis of 611 UHR samples from the National Missing and Unidentified Persons System (NamUs).
• Comparison of anthropologically determined ancestry with ancestry inferred from genome-wide SNP data using principal component analysis (PCA) and model-based clustering.
• Validation of genomic ancestry inference against established reference population samples.

Main Results:

• Significant inconsistencies were observed between anthropological and genomic ancestry assignments.
• Genomic ancestry inference provided robust ancestry calculations for major population groups.
• Discrepancies were particularly notable in admixed populations, indicating potential misattribution by anthropological methods.

Conclusions:

• Forensic anthropological examinations, while valuable, have inherent limitations that necessitate augmentation with SNP-based analyses.
• Genome-wide SNP testing offers a more precise and reliable method for ancestry estimation in UHR cases.
• Further validation and policy revisions are crucial to enhance the accuracy and utility of ancestry determination in forensic investigations.