Quantifying relationships between chromosome organization and chromosomal aberrations

The question of to what extent large scale structure of interphase chromosomes contributes to chromosomal exchange aberrations is discussed for a long time but still remains unclear. We designed the polymer model of 3D organization of a mouse chromosome and simulated X-ray induced chromosomal aberrations exploring two alternative hypotheses: the probability of contacted damaged loci entailing a chromosomal rearrangement is (a) a constant value or (b) not constant, depending on the distribution of DNAsel-hypersensitivity peaks along the chromosome. The latter hypothesis proved to explain the experimental data better than the former, meaning that not only large-scale structure but also local chromatin alterations play a role.