Abdominal symptom, Abnormal axial skeleton morphology, Abnormal CNS myelination, Abnormal emotion/affect behavior, Abnormal fear/anxiety-related behavior, Abnormal glucose homeostasis, Abnormal hair quantity, Abnormality of acid-base homeostasis, Abnormality of blood glucose concentration, Abnormality of body weight, Abnormality of carbohydrate metabolism/homeostasis, Abnormality of cell physiology, Abnormality of central motor function, Abnormality of coordination, Abnormality of eye movement, Abnormality of fluid regulation, Abnormality of head and neck, Abnormality of higher mental function, Abnormality of metabolism/homeostasis, Abnormality of mitochondrial metabolism, Abnormality of movement, Abnormality of muscle morphology, Abnormality of muscle physiology, Abnormality of pyramidal motor function, Abnormality of skeletal morphology, Abnormality of skin adnexa, Abnormality of skull size, Abnormality of the abdomen, Abnormality of the abdominal organs, Abnormality of the cardiovascular system, Abnormality of the central nervous system, Abnormality of the cerebellum, Abnormality of the cerebrospinal fluid, Abnormality of the cerebrum, Abnormality of the eye, Abnormality of the forebrain, Abnormality of the fundus, Abnormality of the glial cells, Abnormality of the hair, Abnormality of the head, Abnormality of the heart, Abnormality of the hindbrain, Abnormality of the integument, Abnormality of the liver, Abnormality of the lung, Abnormality of the metencephalon, Abnormality of the mitochondrion, Abnormality of the musculature, Abnormality of the myocardium, Abnormality of the nervous system, Abnormality of the optic nerve, Abnormality of the peripheral nervous system, Abnormality of the posterior segment of the eye, Abnormality of the respiratory system, Abnormality of the retina, Abnormality of the skeletal system, Abnormality of the skull, Abnormality of vision, Abnormal mitochondria in muscle tissue, Abnormal muscle tone, Abnormal pattern of respiration, Acidosis, Acute encephalopathy, Acute necrotizing encephalopathy, Age of onset, All, Amyotrophy, Ataxia, Autosomal recessive inheritance, Babinski sign, Behavioural/Psychiatric Abnormality, Blindness, Cardiomyopathy, Cerebral edema, Cognitive impairment, Coma, Decreased body weight, Decreased liver function, Dysarthria, Dystonia, Edema, Emotional lability, Encephalopathy, Exercise intolerance, Failure to thrive, Functional motor problems., Functional respiratory abnormality, Gliosis, Global developmental delay, Gonosomal inheritance, Growth abnormality, Hepatic failure, Heterogeneous, Hyperreflexia, Hypertonia, Hypertrichosis, Hypertrophic cardiomyopathy, Hypoglycemia, Hyporeflexia, Increased CSF lactate, Increased serum lactate, Infantile onset, Intellectual disability, Lactic acidosis, Lethargy, Leukodystrophy, Macrocephaly, Malformation of the heart and great vessels, Mitochondrial inheritance, Mode of inheritance, Morphological abnormality of the central nervous system, Muscle weakness, Muscular hypotonia, Nausea and vomiting, Neurological speech impairment, Nystagmus, Onset, Onset and clinical course, Ophthalmoparesis, Ophthalmoplegia, Optic atrophy, Optic disc pallor, Pace of progression, Phenotypic abnormality, Phenotypic variability, Pigmentary retinopathy, Progressive disorder, Progressive macrocephaly, Ptosis, Reduced consciousness/confusion, Reduced tendon reflexes, Respiratory insufficiency, Seizures, Spasticity, Strabismus, Visual impairment, Vomiting, X-linked dominant inheritance, X-linked inheritance.