Significantly, Stetson et al. [257] found that ssDNA fragments from endogenous retroelements accumulate in heart cells of Trex1-null mice, possibly contributing to their characteristic inflammatory myocarditis and death [497] (although a more recent study failed to detect increased ERV expression in Trex1−/− mouse dendritic and macrophage cells [498]). Here, TREX1 is linked to myocarditis.