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All Diseases > Complex II Deficiency
Complex II Deficiency
Alternative Names: Succinate Dehydrogenase Deficiency (SDH Deficiency); Succinate CoQ Reductase Deficiency; Mitochondrial Respiratory Chain Complex II Deficiency; complex 2 Mitochondrial Respiratory Chain Deficiency
Disease Category: Mitochondrial Disorders
An inherited, multisystemic, mitochondrial disorder characterized by protein complex II deficiency. Shortage of this protein complex (structure made up of multiple proteins) disrupts the second step of oxidative phosphorylation, the process by which mitochondria (specialized cell structures) produce energy which the body can use. Typical manifestations include Leigh syndrome, leukodystrophy, which is the destruction of white matter made up of myelin (a fatty coating) around nerves in the brain, as well as seizures, psychomotor regression (loss of mental and motor skills), vision and hearing loss, speech problems, hypertonia (increased muscle tone), extremity muscle atrophy (wasting), hyperreflexia (exaggerated reflexes), cardiomyopathy (heart disease), and fatigue.
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.