Update of Mexican population databases for complex kinship interpretation with twelve and seven X-STRs

Clinical Snapshot

Key Findings

• P Value: Not applicable / not reported (descriptive population genetics study)

• Effect Size: Average 55% increase in likelihood ratios across four representative kinship scenarios when using the updated database (n = 1433) compared to the previous version (n = 933)

• Primary Outcome: Updated Mexican X-STR population database (n = 1433 haplotypes) for 12-marker ArgusX12 panel and 7-marker ForenSeq-compatible subset, with FamlinkX-formatted files for forensic kinship interpretation

• Nnt Or Sensitivity: Not applicable in clinical sense; forensic discrimination capacity and haplotype diversity indices reported but specific values not provided in abstract. LR improvement of ~55% is the primary operational metric.

• Confidence Interval: Not reported

Clinical Application

High feasibility for forensic laboratories already using ArgusX12 (Qiagen) or ForenSeq (Verogen) platforms. FamlinkX-compatible files enable direct integration into existing forensic bioinformatics workflows without additional software investment. The 7-marker subset bridges the gap between CE-based and MPS-based platforms. No direct clinical or PBS/TGA relevance. In the Australian forensic context, this study is methodologically relevant to: (1) the National Criminal Investigation DNA Database (NCIDD) and state forensic biology laboratories considering X-STR panel expansion; (2) forensic identification of individuals from Latin American diaspora communities in Australia; (3) methodological precedent for updating Australian Aboriginal and Torres Strait Islander population databases, which similarly suffer from underrepresentation in global forensic reference databases. The RACGP has no direct guideline relevance. The Australian and New Zealand Forensic Science Society (ANZFSS) and NATA-accredited forensic laboratories would be the relevant professional bodies. The ForenSeq platform (Verogen) is used in Australian forensic laboratories, making the 7-marker subset database directly relevant to local MPS-based kinship workflows. Directly applicable to forensic genetics laboratories performing complex kinship analysis (paternity, sibship, missing persons identification) in Mexican and Latin American populations. Relevant to any forensic context involving individuals of Mexican or Latin American ancestry.

Abstract

BACKGROUND: X-chromosome short tandem repeats (X-STRs) are valuable for resolving complex kinship cases. Most population databases are based on the ArgusX12 kit (Qiagen), using PCR and capillary electrophoresis (CE) to identify length-based (LB) alleles, and are formatted for FamlinkX software. However, haplotype diversity is often underrepresented by population studies, compelling database updates ( https://famlink.se/fx_databases.html ). The ForenSeq DNA Signature Prep kit (Verogen) uses massive parallel sequencing (MPS) to analyze 7 X-STRs and report sequence-based (SB) alleles, for which population databases are currently unavailable. Because these 7 markers are a subset of the ArgusX12 panel, existing LB-based databases can support kinship interpretation of MPS-derived data. METHODS AND RESULTS: We therefore updated a Mexican population database for 12 X-STRs and generated a corresponding 7-marker subset with FamlinkX-compatible files. Using 500 haplotypes from the Investigator Argus X-12 kit QS (Qiagen), we estimated forensic parameters and evaluated the impact of the updated database by calculating likelihood ratios (LRs) in four representative kinship scenarios. The updated database (n = 1433) increased LRs by an average of 55% compared to the previous version (n = 933). CONCLUSIONS: These results support improved forensic interpretation in Mexican and Latin American populations lacking comprehensive national X-STR databases based on ArgusX12 and ForenSeq DNA Signature kits.

References

1. 1.Cortés-Trujillo, I., García-Aceves, M. E., Rojas-Prado, E., López-Armenta, M., Guzmán-González, C. M., Avalos-Navarro, G., Martínez-Cortés, G., Aguilar-Velázquez, J. A., Guardado-Estrada, M., & Rangel-Villalobos, H. (2026). Update of Mexican population databases for complex kinship interpretation with twelve and seven X-STRs. Molecular Biology Reports. PubMed ID: 42364032.