Here we show that in mice that develop Lmna-induced DCM, disruption of the LINC complex, by either genetic ablation or by delivery of a Dominantly Negative acting Sun1 miniprotein (DNSUN1) that destabilizes the LINC complex, significantly ameliorates DCM progression, and leads to at least a fivefold increase in longevity. The gene discussed is SUN1; the disease is familial dilated cardiomyopathy.