2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/105504We consider the behaviour of current fluctuations in the one-dimensional partially asymmetric zero-range process with open boundaries. Significantly, we find that the distribution of large current fluctuations does not satisfy the Gallavotti-Cohen symmetry and that such a breakdown can generally occur in systems with unbounded state space. We also discuss the dependence of the asymptotic current distribution on the initial state of the system.7 pages, 3 figures. v4: minor alterations for consistency with published version to be found at http://www.edpsciences.org/journal/index.cfm?edpsname=eplStatistical Mechanicstext