Combined Oxidative Phosphorylation Deficiency-20-Exome as a Diagnostic Implement

Mitochondrial disorders are phenotypically varied, with serious clinical repercussions. Among them, there is the deficiency of combined oxidative phosphorylation of type 20, which occurs due to a defect in the VARS2 gene. This article presents a case of a 2-year-old female with progressive myoclonic epilepsy and psychomotor regression, with refractoriness to multiple anticonvulsants. The diagnosis was only made after the examination was carried out. Therefore, this article highlights the aspects of this rare disease and the importance of the exome for the diagnosis of rare conditions.