<prompt> most common sign in any mitochondrial inheritence diseases?ataxiaexternal ophthalmoplegiapsychosisneurogenic weakness  <response>: Mitochondrial diseases significant clinical and genetic heterogeneity syndromic and non-syndromic often multi-system diseases onset between bih and senescence a common cause a chronic morbidity and more prevalent than previously thought Common phenotypes in adults PEO-Progressive External Ophthalmoplegia mc K55- Kearns Sayre Syndrome MERRF Myoclonic Epilepsy with Ragged Red Fibers MELAS Mitochondrial Encephalomyopathy, Lactic Acidosis and Stroke-like episodes ref : robbins 10th ed 