Type of inheritance in MELAS is ________

Type of inheritance in MELAS is mitochondrial, which manifests as mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke like episodes Mitochondrial inheritance: Inherited exclusively from the affected mother (ovum) as an individual&;s mitochondrial genome is entirely derived from the mother because sperms contain few mitochondria, which are typically shed upon feilization. Both male and female children born to an affected mother will inherit the disease Pedigree shows mitochondrial inheritance: Mitochondrial inheritance: Caused by mutations of the mitochondrial genome Inherited exclusively from the affected mother (ovum) These include Disease Features Kearn-Sayre syndrome (KSS) Ophthalmoplegia, Pigmentary retinopathy and cardiomyopathy Leigh disease Subacute Necrotizing Encephalomyelopathy Leber hereditary optic neuropathy Acute or Subacute vision loss due to B/L optic atrophy, cerebellar ataxia, hyperreflexia, Babinski sign, Psychiatric symptoms, Peripheral neuropathy, cardiac conduction abnormalities, some have white matter lesion MELAS MERRF Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes Myoclonic epilepsy, ragged red fibers in muscle, ataxia, sensineural deafness NARP (2 Clinical patterns) 1. Neuropathy, ataxia, retinitis pigmentosa, dementia 2. Severe infantile encephalopathy with lesions in basal ganglia Chronic progressive external ophthalmoplegia (CPEO) Ophthalmoplegia, cardiomyopathy, Ptosis, hea block, ataxia, retinal pigmentation, diabetes Pearson pancreatic insufficiency, pancytopenia, lactic acidosis Ref: Nelson textbook of pediatrics 20st edition Pgno: 600