  This paper describes the model for DNA in MATLAB taking into account all of
component atoms. In this model, it is possible to generate sequences with
length 10000 basis pairs available for introducing all types of sequences. Once
the strands are generated, it is studied the DNA damage in the single strand
and double strand. The damage are outcomes of ionising radiation of X-rays when
interacting with the DNA immersed in water. This is a theoretical and
experimental in-vitro study that quantifies the single strand and double strand
damage for different doses of radiation. This can be useful to predict the
exact risks of expositions to radiations. In simulations, it is taken into
account the damage caused by free electrons generated by the effect of the
interaction with the water molecules, this is different to the effect
considered in radiobiology, where indirect damages are due to chemical
reactions. The spatial distribution of the electrons is obtained from Geant4
and here this distribution is used for the creation of rays as
three-dimensional random trajectories through Monte Carlo simulations. It is
also presented the experimental DNA damage through radiating DNA samples
immersed in water with a X-rays unit with Molybdenum target. The damage level
is quantified through Atomic Force Microscopy (AFM). It is possible to conclude
a direct relation between the damage and the radiation doses with the
experimental results.
