STRmix

STRmix performs probabilistic genotyping to interpret complex forensic STR DNA mixture profiles by modeling peak heights and calculating likelihood ratios for evidential evaluation.

Key Features:

• Probabilistic Genotyping (PG): Employs probability models to evaluate alternative genetic explanations for observed DNA profiles and peak heights.
• Likelihood Ratios (LRs): Generates likelihood ratios that compare the probability of the data under competing propositions.
• Proposition Formulation: Requires the formulation of propositions and identification of reasonably assumed contributors to a DNA mixture.
• Mathematical Modeling: Incorporates mathematical models to represent peak heights and their variability.
• Data Modeling: Uses mathematical data modeling to interpret DNA signal information.
• Error Rate Analysis: Supports assessment of precision and error rates based on supporting data.
• Performance Evaluation: Has documented performance, strengths, and limitations from extensive testing.

Scientific Applications:

• Forensic DNA mixture interpretation: Analysis of complex STR mixtures to resolve contributor genotypes and mixture composition.
• Evidential evaluation in legal contexts: Quantitative support of forensic conclusions through likelihood ratios for use in judicial proceedings.

Methodology:

STRmix applies mathematical models of peak heights and their variability within a probabilistic genotyping framework to compute likelihood ratios for competing propositions, and its performance and error rates have been evaluated through extensive testing and data analysis.