Phenotypes associated with the disease myopathy, lactic acidosis, and sideroblastic anemia 1 (OMIM:600462):
- Pallor (HP:0000980): Abnormally pale skin. Evidence: IEA. (OMIM:600462)
- Hypotonia (HP:0001252): Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist. Evidence: PCS. Frequency: 1/2. (PMID:17056637)
- Scapular winging (HP:0003691): Abnormal protrusion of the scapula away from the surface of the back. Evidence: PCS. Frequency: 1/2. (PMID:17056637)
- Infantile onset (HP:0003593): Onset of signs or symptoms of disease between 28 days to one year of life. Evidence: PCS. Frequency: 1/2. (PMID:17056637)
- Pigmentary retinopathy (HP:0000580): An abnormality of the retina characterized by pigment deposition. It is typically associated with migration and proliferation of macrophages or retinal pigment epithelial cells into the retina; melanin from these cells causes the pigmentary changes. Pigmentary retinopathy is a common final pathway of many retinal conditions and is often associated with visual loss. Evidence: PCS. Frequency: 1/2. (PMID:17056637)
- Generalized hypotonia (HP:0001290): Generalized muscular hypotonia (abnormally low muscle tone). Evidence: PCS. Frequency: 1/2. (PMID:17056637)
- Gowers sign (HP:0003391): A phenomenon whereby patients are not able to stand up without the use of the hands owing to weakness of the proximal muscles of the lower limbs. Evidence: PCS. Frequency: 1/2. (PMID:17056637)
- Erythroid hyperplasia (HP:0012132): Increased count of erythroid precursor cells, that is, erythroid lineage cells in the bone marrow. Evidence: TAS. (OMIM:600462)
- Failure to thrive (HP:0001508): Failure to thrive (FTT) refers to a child whose physical growth is substantially below the norm. Evidence: TAS. (OMIM:600462)
- Childhood onset (HP:0011463): Onset of disease at the age of between 1 and 5 years. Evidence: PCS. Frequency: 1/2. (PMID:17056637)
- Hypertelorism (HP:0000316): Interpupillary distance more than 2 SD above the mean (alternatively, the appearance of an increased interpupillary distance or widely spaced eyes). Evidence: PCS. Frequency: 1/2. (PMID:17056637)
- Hyperlordosis (HP:0003307): Abnormally increased curvature (anterior concavity) of the lumbar or cervical spine. Evidence: PCS. Frequency: 1/2. (PMID:17056637)
- Sideroblastic anemia (HP:0001924): Sideroblastic anemia results from a defect in the incorporation of iron into the heme molecule. A sideroblast is an erythroblast that has stainable deposits of iron in cytoplasm (this can be demonstrated by Prussian blue staining). Evidence: PCS. Frequency: 2/2. (PMID:17056637)
- Distichiasis (HP:0009743): Double rows of eyelashes. Evidence: TAS. Frequency: Very rare (HP:0040284). (OMIM:600462)
- High palate (HP:0000218): Height of the palate more than 2 SD above the mean (objective) or palatal height at the level of the first permanent molar more than twice the height of the teeth (subjective). Evidence: IEA. (OMIM:600462)
- Muscle weakness (HP:0001324): Reduced strength of muscles. Evidence: PCS. Frequency: 2/2. (PMID:17056637)
- Cytochrome C oxidase-negative muscle fibers (HP:0003688): An abnormally reduced activity of the enzyme cytochrome C oxidase in muscle tissue. Evidence: PCS. Frequency: 1/1. (PMID:17056637)
- Depressed nasal ridge (HP:0000457): Lack of prominence of the nose resulting from a posteriorly-placed nasal ridge. Evidence: PCS. Frequency: 1/2. (PMID:17056637)
- Intellectual disability (HP:0001249): The term intellectual disability or intellectual developmental disorder is used to describe significantly sub-average intellectual and adaptive functioning based on clinical assessment and as measured by individually administered, appropriately normed, standardized and validated tests of intellectual functioning and adaptive behavior, with onset during the developmental period from infancy through adolescence. Evidence: PCS. Frequency: 1/2. (PMID:17056637)
- Exercise intolerance (HP:0003546): A functional motor deficit where individuals whose responses to the challenges of exercise fail to achieve levels considered normal for their age and gender. Evidence: PCS. Frequency: 0/2. (PMID:17056637)
- Lactic acidosis (HP:0003128): An abnormal buildup of lactic acid in the body, leading to acidification of the blood and other bodily fluids. Evidence: IEA. (OMIM:600462)
- Progressive muscle weakness (HP:0003323). Evidence: IEA. (OMIM:600462)
- Microcephaly (HP:0000252): Head circumference below 2 standard deviations below the mean for age and gender. Evidence: IEA. (OMIM:600462)
- Pappenheimer bodies (HP:0020081): A type of erythrocyte inclusion characterized by basophilic stippling of erythrocytes, that is, by numerous very small coarse or fine blue granules within the cytoplasm with the additional stipulation that the stippled particles are due to iron granules (demonstrable by the Prussian blue stain). Evidence: IEA. (OMIM:600462)
- Ragged-red muscle fibers (HP:0003200): An abnormal appearance of muscle fibers observed on muscle biopsy. Ragged red fibers can be visualized with Gomori trichrome staining as irregular and intensely red subsarcolemmal zones, whereas the normal myofibrils are green. The margins of affect fibers appear red and ragged. The ragged-red is due to the accumulation of abnormal mitochondria below the plasma membrane of the muscle fiber, leading to the appearance of a red rim and speckled sarcoplasm. Evidence: PCS. Frequency: 1/1. (PMID:17056637)
- Joint hypermobility (HP:0001382): The capability that a joint (or a group of joints) has to move, passively and/or actively, beyond normal limits along physiological axes. Evidence: PCS. Frequency: 1/2. (PMID:17056637)
- Increased circulating lactate concentration (HP:0002151): Abnormally increased level of blood lactate (2-hydroxypropanoic acid). Lactate is produced from pyruvate by lactate dehydrogenase during normal metabolism. The terms lactate and lactic acid are often used interchangeably but lactate (the component measured in blood) is strictly a weak base whereas lactic acid is the corresponding acid. Lactic acidosis is often used clinically to describe elevated lactate but should be reserved for cases where there is a corresponding acidosis (pH below 7.35). Evidence: PCS. Frequency: 1/2. (PMID:17056637)
- Hypopituitarism (HP:0040075). Evidence: PCS. Frequency: 1/2. (PMID:17056637)
- Decreased activity of mitochondrial complex I (HP:0011923): A reduction in the activity of the mitochondrial respiratory chain complex I, which is part of the electron transport chain in mitochondria. Evidence: PCS. Frequency: 2/2. (PMID:17056637)
- Increased circulating ferritin concentration (HP:0003281): Increased concentration of ferritin in the blood circulation. Evidence: IEA. (OMIM:600462)
- Restrictive ventilatory defect (HP:0002091): A functional defect characterized by reduced total lung capacity (TLC) not associated with abnormalities of expiratory airflow or airway resistance. Spirometrically, a restrictive defect is defined as FEV1 (forced expiratory volume in 1 second) and FVC (forced vital capacity) less than 80 per cent. Restrictive lung disease may be caused by alterations in lung parenchyma or because of a disease of the pleura, chest wall, or neuromuscular apparatus. Evidence: PCS. Frequency: 1/2. (PMID:17056637)
- Generalized limb muscle atrophy (HP:0009055): Generalized (unlocalized) atrophy affecting muscles of the limbs in both proximal and distal locations. Evidence: IEA. (OMIM:600462)
- Autosomal recessive inheritance (HP:0000007): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in individuals with two pathogenic alleles, either homozygotes (two copies of the same mutant allele) or compound heterozygotes (whereby each copy of a gene has a distinct mutant allele). Evidence: PCS. (PMID:15108122)
- Decreased activity of mitochondrial complex IV (HP:0008347): A reduction in the activity of the mitochondrial respiratory chain complex IV, which is part of the electron transport chain in mitochondria. Evidence: PCS. Frequency: 2/2. (PMID:17056637)
- Microcytic anemia (HP:0001935): A kind of anemia in which the volume of the red blood cells is reduced. Evidence: IEA. (OMIM:600462)
- Delayed puberty (HP:0000823): Passing the age when puberty normally occurs with no physical or hormonal signs of the onset of puberty. Evidence: IEA. (OMIM:600462)
- Growth delay (HP:0001510): A deficiency or slowing down of growth pre- and postnatally. Evidence: PCS. Frequency: 1/2. (PMID:17056637)
- Hypochromic anemia (HP:0001931): A type of anemia characterized by an abnormally low concentration of hemoglobin in the erythrocytes. Evidence: IEA. (OMIM:600462)
- Micrognathia (HP:0000347): Developmental hypoplasia of the mandible. Evidence: IEA. (OMIM:600462)