Abnormal emotion/affect behavior, Abnormal fear/anxiety-related behavior, Abnormal glucose homeostasis, Abnormal hair laboratory examination, Abnormal hair quantity, Abnormality of acid-base homeostasis, Abnormality of amino acid metabolism, Abnormality of blood and blood-forming tissues, Abnormality of blood glucose concentration, Abnormality of body weight, Abnormality of carbohydrate metabolism/homeostasis, Abnormality of carboxylic acid metabolism, Abnormality of central motor function, Abnormality of coagulation, Abnormality of coordination, Abnormality of eye movement, Abnormality of genital physiology, Abnormality of hair texture, Abnormality of higher mental function, Abnormality of metabolism/homeostasis, Abnormality of movement, Abnormality of muscle fibers, Abnormality of muscle morphology, Abnormality of muscle physiology, Abnormality of pyramidal motor function, Abnormality of skin adnexa, Abnormality of the abdomen, Abnormality of the abdominal organs, Abnormality of the abdominal wall, Abnormality of the anterior segment of the eye, Abnormality of the biliary system, Abnormality of the cardiovascular system, Abnormality of the central nervous system, Abnormality of the cerebellum, Abnormality of the cerebrospinal fluid, Abnormality of the coagulation cascade, Abnormality of the ear, Abnormality of the endocrine system, Abnormality of the eye, Abnormality of the fundus, Abnormality of the genital system, Abnormality of the genitourinary system, Abnormality of the glial cells, Abnormality of the hair, Abnormality of the heart, Abnormality of the hindbrain, Abnormality of the integument, Abnormality of the lens, Abnormality of the liver, Abnormality of the lung, Abnormality of the metencephalon, Abnormality of the middle ear, Abnormality of the musculature, Abnormality of the myocardium, Abnormality of the nervous system, Abnormality of the optic nerve, Abnormality of the posterior segment of the eye, Abnormality of the respiratory system, Abnormality of the retina, Abnormality of the retinal pigment epithelium, Abnormality of the urinary system, Abnormality of the urinary system physiology, Abnormality of urine homeostasis, Abnormal muscle tone, Abnormal pattern of respiration, Abnormal retinal pigmentation, Acidosis, Aciduria, Age of onset, All, Alopecia, Aminoaciduria, Ataxia, Autosomal recessive inheritance, Behavioural/Psychiatric Abnormality, Bilateral conductive hearing impairment, Cardiomyopathy, Cataract, Cerebellar atrophy, Cholestasis, Coarse hair, Cognitive impairment, Conductive hearing impairment, Decreased body weight, Decreased liver function, Decreased mitochondrial complex III activity in liver tissue, Depression, Dysarthria, Dystonia, EEG abnormality, Emotional lability, Encephalopathy, Exercise intolerance, Failure to thrive, Functional abnormality of the middle ear, Functional motor problems., Functional respiratory abnormality, Gliosis, Global developmental delay, Growth abnormality, Hair shafts flattened at irregular intervals and twisted through 180 degrees about their axes, Hallucinations, Hearing abnormality, Hearing impairment, Hepatic steatosis, Heterogeneous, Hyperreflexia, Hypertonia, Hypertrichosis, Hypertrophic cardiomyopathy, Hypoglycemia, Hypogonadism, Hypogonadotrophic hypogonadism, Increased CSF lactate, Increased serum lactate, Infantile onset, Intellectual disability, Lactic acidosis, Malformation of the heart and great vessels, Metabolic acidosis, Microvesicular hepatic steatosis, Mitochondrial encephalopathy, Mitochondrial inheritance, Mode of inheritance, Morphological abnormality of the central nervous system, Muscle weakness, Muscular hypotonia, Neurological speech impairment, Neurophysiological abnormality, Nystagmus, Onset, Onset and clinical course, Ophthalmoparesis, Ophthalmoplegia, Optic atrophy, Pace of progression, Phenotypic abnormality, Phenotypic variability, Pigmentary retinopathy, Progressive disorder, Puberty and gonadal disorders, Ragged-red muscle fibers, Respiratory insufficiency, Retinitis pigmentosa, Rhabdomyolysis, Seizures, Sparse or absent hair, Spasticity.