Improved second-degree kinship analysis using the FGID forensic four-in-one DNA typing kit

Area of Science:

• Forensic genetics
• Human identification
• Molecular biology

Background:

• Complex kinship identification relies on genetic markers for accuracy.
• The study evaluates the FGID Forensic Four-in-one DNA typing kit using autosomal short tandem repeats (A-STRs) and single nucleotide polymorphisms (A-SNPs).
• The DNBSEQ-G99RS platform was utilized for high-throughput sequencing of genetic markers.

Discussion:

• Increased genetic markers (66 A-STRs and 132 A-SNPs) enhanced the power of kinship analysis for second-degree relatives.
• Likelihood ratio (LR) values improved for related pairs and decreased for unrelated individuals compared to previous kits.
• Sensitivity, specificity, and predictive values exceeded 0.9600, with 96.80% accurate classification of relationship types.

Key Insights:

• The FGID kit with expanded markers significantly improves second-degree kinship identification accuracy.
• Sequence-based STR analysis yielded lower identical-by-state (IBS) values than length-based STRs.
• The system demonstrates high performance metrics, including sensitivity and specificity, for forensic applications.

Outlook:

• Further validation of the FGID kit with larger and diverse populations is warranted.
• Integration of advanced sequencing platforms can further refine kinship analysis.
• The enhanced system holds potential for improving casework in forensic genetics and establishing biological relationships.