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All Diseases > Complex IV Deficiency
Complex IV Deficiency
Alternative Names: Mitochondrial Complex IV Deficiency (MC4DN); Complex 4 Mitochondrial Respiratory chain Deficiency; Cytochrome C Oxidase Deficiency (COX Deficiency)
Disease Category: Mitochondrial Disorders
An inherited, multisystemic, mitochondrial disorder characterized by protein complex IV deficiency. Shortage of this protein complex (structure made up of multiple proteins) disrupts the fourth step of oxidative phosphorylation, the process by which mitochondria (specialized cell structures) produce most of the body's energy. Signs include Leigh syndrome, encephalopathy (brain disease), lack of coordination, feeding difficulties, hypotonia (low muscle tone), muscle weakness, seizures, lactic acidosis (high blood lactate levels), intellectual disability, developmental regression (loss of acquired skills), heart disease, and kidney or liver problems.
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.