Systematic evaluation of STRmix™ performance on degraded DNA profile data

Area of Science:

• Forensic Science
• Molecular Biology
• Genetics

Background:

• DNA degradation poses challenges in forensic analysis.
• STRmix™ is a key software for DNA interpretation.
• Validation of software capabilities is crucial for forensic science.

Purpose of the Study:

• To assess the DNA degradation modeling capacity of STRmix™ software.
• To validate STRmix™ v2.4 for forensic casework.
• To evaluate STRmix™'s performance with degraded DNA profiles.

Main Methods:

• Generated STR profile data from DNA exposed to DNase I over time.
• Analyzed degraded DNA profiles using STRmix™ v2.4.
• Compared STRmix™ degradation parameters to ground truth and assessed weight-of-evidence statistics.

Main Results:

• STRmix™ v2.4 effectively modeled DNA degradation across various time intervals.
• Degradation modeling parameters from STRmix™ aligned well with ground truth.
• Weight-of-evidence statistics for degraded profiles were comparable to intact profiles.

Conclusions:

• The degradation model in STRmix™ can handle a wide range of degraded STR profile data.
• This validation expands the application of probabilistic genotyping in forensic science.
• Confirms STRmix™'s utility for analyzing degraded forensic samples.