  We compute the pion quark Generalised Parton Distribution H and quark Double
Distributions in a coupled Bethe-Salpeter and Dyson-Schwinger approach in terms
of quark flavors or isospin states. We use analytic expressions inspired by the
numerical resolution of Dyson-Schwinger and Bethe-Salpeter equations. We obtain
an analytic expression for the pion Generalised Parton Distribution at a low
scale. Our model fulfils most of the required symmetry properties and compares
very well to experimental pion form factor or valence parton distribution
function experimental data. In addition, we have highlighted limitations of the
so-called impulse approximation, which breaks symmetries when computing the
valence parton distribution function. Doing so, we introduced new terms which
were neglected before. Finally, we also shed light on a specific property of
the pion GPD: Polyakov soft pion theorem.
