Mitochondrial Dysfunction due to Novel COQ8A Variation with Poor Response to CoQ10 Treatment: A Comprehensive Study and Review of Literatures

AbstractCOQ8A plays an important role in the biosynthesis of coenzyme Q10 (CoQ10), and variations inCOQ8A gene are associated with primary CoQ10 deficiency-4 (COQ10D4), also known as COQ8A-ataxia. The current understanding of the association between the specific variant type, the severity of CoQ10 deficiency, and the degree of oxidative stress in individuals with primary CoQ10 deficiencies remains uncertain. Here we provide a comprehensive analysis of the clinical and genetic characteristics of an 18-year-old patient with COQ8A-ataxia, who exhibited novel compound heterozygous variants (c.1904_1906del and c.637C  >  T) in theCOQ8A gene. These variants reduced the expression levels of COQ8A and mitochondrial proteins in the patient ’s muscle and skin fibroblast samples, contributed to mitochondrial respiration deficiency, increased ROS production and altered mitochondrial membrane potential. It is worth noting that the optimal treatment for COQ8A-ataxia remains uncertain. Presently, therapy consists of CoQ10 supplementati on, however, it did not yield significant improvement in our patient's symptoms. Additionally, we reviewed the response of CoQ10 supplementation and evolution of patients in previous literatures in detail. We found that only half of patients could got notable improvement in ataxia. This research aim s to expand the genotype–phenotype spectrum of COQ10D4, address discrepancies in previous reviews regarding the effectiveness of CoQ10 in these diso...
Source: The Cerebellum - Category: Neurology Source Type: research