Human CoQ10 deficiencies
Article first published online: 7 APR 2009
Copyright © 2008 International Union of Biochemistry and Molecular Biology, Inc.
Volume 32, Issue 1-4, pages 113–118, 2008
How to Cite
Quinzii, C. M., López, L. C., Naini, A., DiMauro, S. and Hirano, M. (2008), Human CoQ10 deficiencies. BioFactors, 32: 113–118. doi: 10.1002/biof.5520320113
- Issue published online: 7 APR 2009
- Article first published online: 7 APR 2009
- NIH. Grant Number: NS11766, HD32062
- Muscular Dystrophy Association, and by the Marriott Mitochondrial Disorder Clinical Research Fund (MMDCRF)
Coenzyme Q10 (CoQ10 or ubiquinone) is a lipid-soluble component of virtually all cell membranes and has multiple metabolic functions. A major function of CoQ10 is to transport electrons from complexes I and II to complex III in the respiratory chain which resides in the mitochondrial inner membrane. Deficiencies of CoQ10 (MIM 607426) have been associated with four major clinical phenotypes: 1) encephalomyopathy characterized by a triad of recurrent myoglobinuria, brain involvement, and ragged-red fibers; 2) infantile multisystemic disease typically with prominent nephropathy and encephalopathy; 3) cerebellar ataxia with marked cerebellar atrophy; and 4) pure myopathy. Primary CoQ10 deficiencies due to mutations in ubiquinone biosynthetic genes (COQ2, PDSS1, PDSS2, and ADCK3 [CABC1]) have been identified in patients with the infantile multisystemic and cerebellar ataxic phenotypes. In contrast, secondary CoQ10 deficiencies, due to mutations in genes not directly related to ubiquinone biosynthesis (APTX, ETFDH, and BRAF), have been identified in patients with cerebellar ataxia, pure myopathy, and cardiofaciocutaneous syndrome. In many patients with CoQ10 deficiencies, the causative molecular genetic defects remain unknown; therefore, it is likely that mutations in additional genes will be identified as causes of CoQ10 deficiencies.