POLG mutations associated with Alpers ' syndrome and mitochondrial DNA depletion .
B-GeneOrGeneProduct O O O B-DiseaseOrPhenotypicFeature I-DiseaseOrPhenotypicFeature I-DiseaseOrPhenotypicFeature O B-DiseaseOrPhenotypicFeature I-DiseaseOrPhenotypicFeature I-DiseaseOrPhenotypicFeature O