<prompt> All are selected mitochondrial disease EXCEPTLebers optic atrophyKearns- sayre syndromeProgressive external ophthalmoplegiaSpino-cerebellar ataxia  <response>: Spino- cerebellar ataxia 400-HI7th Spino-cerebellar ataxia is a selected trinucleotide repeat disordersSelected trinucleotide repeat disorders are - X- chromosomal spinobulbar muscular atrophy SBMA, fragile-x syndrome, Dystrophia myotonica, Huntington disease spino-cerebellar ataxia Dentorubral pallido luysiane atrophy DRPLA, Friedreich ataxiaSelected Mitochondrial Diseases 400-H17th MELAS syndrome: mitochondrial myopathy with encephalopathy, lactic acidosis and stroke Lebers optic atrophy: hereditary optical neuropathy Kearns-sayre syndrome KSS: ophthalmoplegia, pigmental degeneration of the retina, cardiomyopathy MERRF syndrome- myoclonic epilepsy and ragged- red fibers Neurogenic muscular weakness with ataxia and retinitis pigmentosa NARP Porgressive external ophthalmoplegia CEOP Pearson syndrome PEAR bone marrow and pancreatic failure Autosomal dominant Inherited mitochondrial myopathy with mitochondrial deletion ADMIMY Somatic mutations in cytochrome b gene exercise intolerance, lactic acidosis, complex III deficiency muscle pain ragged- red fibers Inherited mitochondrial disorders are transmitted in a matrilineal fashion; all children from an affected mother will inherit the disease but it will not be transmitted from an affected father to his children Mitochondrial disorders have clinical manifestations - 3groups- Chronic progressive external ophthalmoplegia CPEO- Skeletal muscle - CNS syndrome- Pure myopathy simulating muscular dystrophy or metabolic myopathyMitochondrial DNA Depletion Myopathy 2691 -H17th- Usually presents in neonatal period with weakness hypotonia and delayed motor milestones- Proximal muscle weakness- Seizure and cardiomyopathy- CK levels reaches levels of 20 to30 times normal- Resting lactate normal to mildely elevated- EMG is myopathy, reggedrcd fibres are seen on muscle biopsy- The mt DNA depletion syndrome is inherited as an autosomal recessive AR- Mutations- TK2 gene on chromosome 16q 22 encoding thyidine kinase-2- No specific treatment 