Human Coenzyme Q10 Deficiency

Ubiquinone (coenzyme Q10 or CoQ10) is a lipid-soluble component of virtually all cell membranes and has multiple metabolic functions. Deficiency of CoQ10 (MIM 607426) has been associated with five different clinical presentations that suggest genetic heterogeneity, which may be related to the multiple steps in CoQ10 biosynthesis. Patients with all forms of CoQ10 deficiency have shown clinical improvements after initiating oral CoQ10 supplementation. Thus, early diagnosis is of critical importance in the management of these patients. This year, the first molecular defect causing the infantile form of primary human CoQ10 deficiency has been reported. The availability of genetic testing will allow for a better understanding of the pathogenesis of this disease and early initiation of therapy (even presymptomatically in siblings of patients) in this otherwise life-threatening infantile encephalomyopathy.