Internal validation of an improved system for forensic application: a 41-plex Y-STR panel

Area of Science:

• Forensic Genetics
• Human Population Genetics
• Molecular Biology

Background:

• Y-chromosome short tandem repeats (Y-STRs) are crucial for forensic investigations.
• Limitations exist with low-medium mutating Y-STRs in inbred populations and rapidly mutating Y-STRs potentially causing lineage exclusion.
• Combining Y-STRs with varying mutation rates aids in distinguishing male individuals and lineages.

Purpose of the Study:

• To develop and validate a novel 6-dye, 41-plex Y-STR panel for forensic applications.
• To assess the panel's performance in differentiating related males and its compatibility with existing kits.
• To evaluate the utility of Y-InDels for degraded sample analysis.

Main Methods:

• Development of a 41-plex Y-STR panel including 17 Yfiler loci, nine rapidly mutating (RM) Y-STRs, 15 low-medium mutating Y-STRs, and three Y-InDels.
• Comprehensive developmental validation including precision, stutter, specificity, sensitivity, concordance, inhibitor, and mixture testing.
• Assessment of adaptability to various case-type samples and degraded DNA.

Main Results:

• The novel 41-plex Y-STR panel demonstrated efficiency, accuracy, and reliability.
• The panel showed excellent adaptability for direct amplification of diverse forensic samples.
• Improved discrimination of related males and compatibility with widely used Y-STR kits were confirmed.
• Inclusion of Y-InDels enhanced degraded sample analysis.

Conclusions:

• The developed 41-plex Y-STR panel is a powerful and reliable tool for forensic casework.
• This multiplex system significantly enhances the ability to distinguish related males and supports familial searching.
• The panel facilitates population database construction and improves analysis of challenging samples like degraded DNA.