COQ8A and autosomal recessive ataxia due to ubiquinone deficiency: In contrast with the Coq gene KOs previously mentioned, the lack of COQ8A in mice (Coq8a−/−) resulted in a mild phenotype with progressive cerebellar ataxia, mild exercise intolerance, and moderate CoQ deficiency, recapitulating the more frequent features of autosomal-recessive cerebellar ataxia type 2 (ARCA2, the most frequent form of hereditary CoQ deficiency in humans) [115].