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All Diseases > Myoclonus Epilepsy Ragged-Red Fibers
Myoclonus Epilepsy Ragged-Red Fibers (MERRF)
Alternative Names: Fukuhara Disease; MERRF Syndrome; Myoclonic Epilepsy Associated with Ragged-Red Fibers; Myoencephalopathy Ragged-Red Fiber Disease
Disease Category: Mitochondrial Disorders
A rare, multisystemic disorder affecting the nervous system and muscles. Symptoms include myoclonus (muscle twitches), muscle weakness, seizures, spasticity (muscle rigidity), ataxia (lack of coordination), peripheral neuropathy (sensory changes and muscle weakness in the extremities), intellectual deficits, optic nerve atrophy (wasting), short stature, cardiomyopathy (heart disease), and, less commonly, lipomas (fatty tumors under the skin). Muscle cells from affected individuals reveal abnormal "ragged-red" muscle fibers with a special stain and viewed under a microscope.
Research groups studying this disease
North American Mitochondrial Disease Consortium (NAMDC)View Disease Definition
United Mitochondrial Disease Foundation
Promotes research and education for the diagnosis, treatment, and cure of mitochondrial disorders while providing support to those affected.
Improves quality of life for people affected by mitochondrial disease through education, outreach, advocacy, and clinical research initiatives.