Abstract: Helitrons are a class of prolific transposable elements in the Arabidopsis thaliana genome. Although 37 families were identified after the
recent discovery of Helitrons, no systematic classification is available because of the high variability of helitronic sequences. Since transposition
proteins are assumed to interact with Helitron termini, a Helitron model was formalized based on terminus characterization in order to carry out an
exhaustive analysis of all possible combinations of the pairs of termini present. This combinatorics approach resulted in the discovery of a number
of new Helitron elements corresponding to termini associations from distinct previously-described Helitron families. The occurrence matrix of
termini combinations yielded a structure that revealed clusters of Helitron families.