: Kearns-Sayre Syndrome (KSS) is a multisystem disorder caused by a dysfunction of the oxidative phosphorylation system within mitochondria. Mitochondrial DNA (mtDNA) rearrangements are a key molecular feature of this disease, which manifest a broad phenotypic spectrum. | A novel mitochondrial DNA deletion in a patient with Kearns-Sayre syndrome: A late-onset of the fatal cardiac conduction deficit and cardiomyopathy accompanying long-term rGH treatment