Power analyses to inform Duplex Sequencing study designs for MutaMouse liver and bone marrow

Area of Science:

• Toxicology
• Genetics
• Next-Generation Sequencing

Background:

• Regulatory genetic toxicology testing identifies mutagenic hazards.
• Duplex Sequencing (DS) offers improved accuracy and broader applicability over conventional mutagenicity assays.
• Power analyses are crucial for optimizing DS in regulatory toxicology study designs.

Purpose of the Study:

• To explore study designs for sufficient power in chemical mutagenicity assessment using Duplex Sequencing.
• To determine optimal sample sizes and sequencing parameters for regulatory toxicology testing with DS.
• To provide foundational data for establishing robust mutagenicity testing protocols using DS.

Main Methods:

• Analysis of MutaMouse bone marrow and liver samples using Duplex Sequencing (DS) and TwinStrand's Mouse Mutagenesis Panel.
• Collection of empirical data on duplex reads, baseline mutation frequencies, and standard deviations.
• Simulation analyses based on empirically derived parameters to assess power for various effect sizes and sample sizes.

Main Results:

• Average duplex reads exceeded 8.4 x 10^8 for liver and 9.5 x 10^8 for bone marrow.
• Baseline mutation frequencies were consistently low (4.6 x 10^-8) with manageable animal-to-animal variability.
• A sample size of four animals per group achieved over 80% power to detect a two-fold change in mutation frequency.

Conclusions:

• Four animals per group are sufficient for DS-based mutagenicity testing to detect biologically relevant changes.
• Empirical data and simulation analyses provide a basis for designing efficient regulatory toxicology studies using DS.
• DS is a powerful tool for advancing genetic toxicology assessment, offering enhanced sensitivity and reliability.