Calculation of the initial DNA damage induced by alpha particles in comparison with protons and electrons using Geant4-DNA

Abstract

Purpose: Interaction of ionizing radiations with cells leads to single- and double-strand breaks (SSBs and DSBs) as well as base lesions of DNA. Employing the Geant4-DNA toolkit, we simulated the transportation of primary alphas and secondary particles in liquid water to study the damage in the form of SSBs and DSBs.

Materials and Methods: Simulations were performed in a spherical water medium, where we used a B-DNA model and classified the DNA damage and its complexity. We assumed that in a certain vicinity of the DNA volume, energy depositions of more than 17.5 eV or hydroxyl radicals with a chemical-reaction probability of 0.13 would lead to strand breaks.

Results: The results of 2 to 20 MeV alpha particles showed that more than 65% of the energy-deposition cases within the DNA volume would result in a form of break. The frequency pattern of higher-complexity damage types appeared to peak at higher deposited energies.

Conclusion: We observed a reasonable agreement in terms of trend and value between our DSB yield results and experimental data. The yield results, as function of LET, suggested independence from particle type and converge to some extent at large LET. This manifests the dominant contribution of secondary electrons.

Keywords:

• Monte Carlo simulations
• Geant4-DNA
• alpha particle
• chemical/physical interaction
• DNA damage
• double-strand breaks

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Hossein Moeini

Hossein Moeini, PhD in Nuclear Structure Physics from University of Groningen (Kernfysisch Versneller Instituut), Groningen, Netherlands in 2010. He is an Assistant Professor in Physics Department, Shiraz University, Shiraz, Iran.

Mojtaba Mokari

Mojtaba Mokari, PhD in Physics from Isfahan University of Technology, Isfahan, Iran in 2018. He is an Assistant Professor in Physics Department, Behbahan Khatam Alanbia University of Technology, Behbahan, Iran. He has been working on the dosimetry and microdosimetry, radiation therapy devices and the process of ionizing radiation with the mater.

Mohammad Hassan Alamatsaz

Mohammad Hassan Alamatsaz is an Associate Professor in Physics Department, Isfahan University of Technology, Isfahan, Iran. PhD in High Energy Physics from University of London (University college) in 1984. MSc in Nuclear & Particle Physics from University of London (Bedford College) in 1979. BSc in Physics from Isfahan University in 1976.

Reza Taleei

Reza Taleei is an Assistant Professor of Medical Physics at Thomas Jefferson University Hospital. PhD in Medical Science from Karolinska Institutet, Stockholm Sweden. Previously he was an Assistant Professor at University of Virginia. He is board certified in Medical Physics. He has been working on DNA damage and repair models induced by ionizing radiation.