Track structures, DNA targets and radiation effects in the biophysical Monte Carlo simulation code PARTRAC

Area of Science:

• Radiation physics and radiobiology
• Computational biophysics
• Genomic DNA damage modeling

Background:

• Understanding the biological impact of ionizing radiation requires detailed knowledge of radiation track structures.
• Simulating the complex interactions of radiation with biological matter is crucial for accurate risk assessment.
• Previous models lacked the resolution to capture atomic-level DNA structures and repair dynamics.

Purpose of the Study:

• To review the PARTRAC simulation suite for Monte Carlo calculations of radiation track structures.
• To present a multi-scale target model of genomic DNA in human cells at atomic resolution.
• To extend modeling capabilities to include DNA repair processes for enhanced radiation risk prediction.

Main Methods:

• Utilizing comprehensive Monte Carlo simulations to model track structures.
• Employing a multi-scale target model of genomic DNA within human fibroblasts and lymphocytes.
• Incorporating atomic resolution characterization of DNA structures.
• Extending the model to simulate DNA repair processes over extended timescales.

Main Results:

• Detailed recapitulation of physical, physico-chemical, and chemical stages of radiation damage induction.
• Demonstration of a multi-scale target model for genomic DNA.
• Successful extension of the model to include DNA repair mechanisms.
• Establishment of a foundation for superior radiation risk predictions.

Conclusions:

• The PARTRAC suite provides advanced tools for simulating ionizing radiation track structures and biological effects.
• The atomic-resolution DNA model and extended simulation of repair processes significantly advance radiobiology.
• This work paves the way for more accurate and reliable predictions of radiation-induced health risks.