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Chromosome aberrations induced by light ions: Monte Carlo simulations based on a mechanistic model
- Source :
- International journal of radiation biology. 75(1)
- Publication Year :
- 1999
-
Abstract
- To investigate the mechanisms underlying the induction of chromosome aberrations by ionizing radiation, focusing attention on DNA damage severity, interphase chromosome geometry and the distribution of DNA strand breaks.An ab initio biophysical model of aberration induction in human lymphocytes specific for light ions was developed, based on the assumption that 'complex lesions' (clustered DNA breaks) produce aberrations, whereas less severe breaks are repaired. It was assumed that interphase chromosomes are spatially localized and that chromosome break free-ends rejoin pairwise randomly; the unrejoining of a certain fraction of free-ends was assumed to be possible, and small fragments were neglected in order to reproduce experimental conditions. The yield of different aberrations was calculated and compared with some data obtained using Giemsa or FISH techniques.Dose-response curves for dicentrics and centric rings (Giemsa) and for reciprocal, complex and incomplete exchanges (FISH) were simulated; the ratio between complex and reciprocal exchanges was also calculated as a function of particle type and LET. The results showed agreement with data from lymphocyte irradiation with light ions.The results suggest that clustered DNA breaks are a critical damage type for aberration induction and that interphase chromosome localization plays an important role. Moreover, the effect of a given particle type is related both to the number of induced complex lesions and to their spatial distribution.
- Subjects :
- DNA damage
Monte Carlo method
Linear energy transfer
Biology
Azure Stains
Ionizing radiation
chemistry.chemical_compound
Optics
Humans
Radiology, Nuclear Medicine and imaging
Computer Simulation
Lymphocytes
In Situ Hybridization, Fluorescence
Chromosome Aberrations
Radiological and Ultrasound Technology
Models, Genetic
business.industry
Interphase Chromosome
Chromosome
Dose-Response Relationship, Radiation
Alpha Particles
chemistry
Biophysics
Interphase
Protons
business
Monte Carlo Method
DNA
Subjects
Details
- ISSN :
- 09553002
- Volume :
- 75
- Issue :
- 1
- Database :
- OpenAIRE
- Journal :
- International journal of radiation biology
- Accession number :
- edsair.doi.dedup.....3f6363210c77105d3d3985f6e9904b63