Developmental validation of the Microreader™ RM-Y ID System: a new rapidly mutating Y-STR 17-plex system for forensic...

Area of Science:

• Forensic Genetics
• Human Population Genetics

Background:

• Y-chromosomal short tandem repeats (Y-STRs) are crucial for male lineage analyses but often lack discriminatory power for closely related individuals.
• Rapidly mutating Y-STRs (RM Y-STRs) offer enhanced resolution for differentiating males within the same paternal lineage.

Purpose of the Study:

• To validate the efficiency and accuracy of the new Microreader™ RM-Y ID System for amplifying 17 RM Y-STRs.
• To assess the forensic characteristics and mutation rates of these RM Y-STRs in a specific population.

Main Methods:

• Developmental validation including PCR-based studies, sensitivity, stability, species specificity, mixture, stutter, and precision analyses.
• Analysis of 250 DNA-confirmed father-son pairs to evaluate forensic discrimination power and mutation rates.
• Optimization of conditions for hematin, humic acid, and tannic acid concentrations for full profile generation.

Main Results:

• The Microreader™ RM-Y ID System successfully amplified 17 RM Y-STRs, providing full profiles under optimized conditions.
• The system demonstrated high sensitivity in detecting male/male mixtures (up to 19:1) and female/male mixtures (up to 24,000:1).
• Analysis of father-son pairs revealed high forensic discrimination power (HD=1) and mutation rates ranging from 4 × 10⁻³ to 8.8 × 10⁻².

Conclusions:

• The Microreader™ RM-Y ID System is validated as an effective tool for RM Y-STR studies.
• The kit enables absolute individualization of interrelated male individuals, significantly improving forensic analysis capabilities.