{"Name":"Leukoencephalopathy-thalamus and brainstem anomalies-high lactate syndrome","DiseaseID__c":"GARD:0013381","id":13381,"encodedName":"leukoencephalopathy-thalamus-and-brainstem-anomalies-high-lactate-syndrome","IsDeleted":false,"Disease_Name_Full__c":"Leukoencephalopathy-thalamus and brainstem anomalies-high lactate syndrome","Xref_IDs__c":"763366000; C4706421; DOID:0111493; MEDGEN:1645614; MONDO:0013971; OMIM:614924; ORPHA:314051","USA_Estimate__c":null,"No_of_Specialist_Tagsa__c":3,"No_of_ClinGen_records__c":0,"No_of_GeneReviews__c":0,"No_of_HHS_records__c":1,"World_Estimate__c":null,"No_of_HRSA_records__c":0,"Evidence_Based_Score__c":1,"No_of_Disease_Descriptions__c":5,"Disease_Characteristics_Score__c":8,"No_of_Age_at_Onset__c":2,"Description_Source__c":"MONDO:0013971","Disease_Description__c":"A rare, genetic neurological disorder defined by early-onset of neurologic symptoms, biphasic clinical course, unique MRI features (incl. extensive, symmetrical, deep white matter abnormalities), and increased lactate in body fluids. The severe form is characterized by delayed psychomotor development, seizures, early-onset hypotonia, and persistently increased lactate levels. The mild form usually presents with irritability, psychomotor regression after six months of age, and temporary high lactate levels, with overall clinical improvement from the second year onward.","GARD_Name__c":"Leukoencephalopathy-thalamus and brainstem anomalies-high lactate syndrome","GARD_Synonym__c":"combined oxidative phosphorylation defect type 12; combined oxidative phosphorylation deficiency 12; combined oxidative phosphorylation deficiency caused by mutation in ears2; combined oxidative phosphorylation deficiency type 12; coxpd12; coxpd12 - combined oxidative phosphorylation defect type 12; ears2 combined oxidative phosphorylation deficiency; leukoencephalopathy with thalamus and brainstem involvement and high lactate; leukoencephalopathy, thalamus and brainstem anomalies, high lactate syndrome; ltbl","Curated_Disease_Description_Source__c":"GARD:0013381","Curated_Disease_Description__c":"Leukoencephalopathy with thalamus and brainstem involvement and high lactate (LTBL) is a disorder that affects the brain. LTBL is one of a group of genetic disorders called leukodystrophies, which feature abnormalities of the nervous system's white matter. White matter consists of nerve fibers covered by a fatty substance, called myelin, that insulates nerve fibers and promotes the rapid transmission of nerve impulses. LTBL is characterized by distinct changes in the brain, which can be seen using magnetic resonance imaging (MRI). These abnormalities typically involve white matter in regions of the brain known as the cerebrum and cerebellum. Abnormalities can also be seen in other regions of the brain, including the brainstem, which is the part that connects to the spinal cord. Affected brain regions include the thalamus, midbrain, pons, and medulla oblongata. Thinning of the tissue that connects the left and right halves of the brain (the corpus callosum) also occurs in people with LTBL. In addition, most affected individuals have a high level of a substance called lactate in the brain and elsewhere in the body. The severity of the condition varies. Mildly affected individuals usually develop signs and symptoms after the age of 6 months. Loss of mental and movement abilities (psychomotor regression), muscle stiffness (spasticity), and extreme irritability are common, and some people with mild LTBL develop seizures. However, after age 2, the signs and symptoms of the condition improve: affected children regain some psychomotor abilities, seizures are reduced or disappear, MRI results become more normal, and lactate levels drop. Severely affected individuals have features that begin soon after birth. These infants typically have delayed development of mental and movement abilities (psychomotor delay), weak muscle tone (hypotonia), involuntary muscle tensing (dystonia), muscle spasticity, and seizures. Some have extremely high levels of lactate (lactic acidosis), which can cause serious breathing problems and an abnormal heartbeat. Liver failure occurs in some severely affected infants. In severe cases, the signs and symptoms do not improve and can be life-threatening. In some people with LTBL, the features fall between mild and severe.","Curated_USA_Estimate_Source__c":null,"Curated_USA_Estimate__c":null,"Age_at_Onset_Snippet_Text__c":"as a Newborn and as an Infant","SourceID__c":null,"Deprecated__c":"No","Disease_Concept_Type__c":"Rare Disease Entity","MONDO_ID__c":"MONDO:0013971","ORPHANET_ID__c":"ORPHA:314051","Replaced_By_ID__c":null,"Display_Spanish_Disease_Name__c":"Síndrome de leucoencefalopatía-anomalías del tálamo y tallo cerebral-lactato elevado","Spanish_Description_Source__c":"ORPHA:314051","Spanish_Description__c":"Es un trastorno neurológico poco frecuente de origen genético caracterizado por síntomas neurológicos de inicio temprano, curso clínico bifásico, características únicas de RM (incluyendo anomalías extensas y simétricas de la sustancia blanca profunda) y un aumento de los niveles de lactato en los fluidos corporales. La forma grave se caracteriza por retraso en el desarrollo psicomotor, crisis, hipotonía de inicio temprano y niveles de lactato persistentemente elevados. La forma leve generalmente se presenta con irritabilidad, regresión psicomotora después de los seis meses de edad y niveles de lactato temporalmente elevados, con mejoría clínica generalizada a partir del segundo año.","Spanish_Disease_Name__c":"síndrome de leucoencefalopatía-anomalías del tálamo y tallo cerebral-lactato elevado","Spanish_GARD_Synonym__c":"coxpd12; deficiencia combinada de la fosforilación oxidativa tipo 12; ltbl","Category_Linearization__c":"ORPHA:98006","icd10_id__c":null,"mesh_id__c":null,"omim_id__c":null,"snomed_id__c":null,"umls_id__c":null,"GARD_Disease__c":[{"Curated_Disease_Description__c":"Leukoencephalopathy with thalamus and brainstem involvement and high lactate (LTBL) is a disorder that affects the brain. LTBL is one of a group of genetic disorders called leukodystrophies, which feature abnormalities of the nervous system's white matter. White matter consists of nerve fibers covered by a fatty substance, called myelin, that insulates nerve fibers and promotes the rapid transmission of nerve impulses. LTBL is characterized by distinct changes in the brain, which can be seen using magnetic resonance imaging (MRI). These abnormalities typically involve white matter in regions of the brain known as the cerebrum and cerebellum. Abnormalities can also be seen in other regions of the brain, including the brainstem, which is the part that connects to the spinal cord. Affected brain regions include the thalamus, midbrain, pons, and medulla oblongata. Thinning of the tissue that connects the left and right halves of the brain (the corpus callosum) also occurs in people with LTBL. In addition, most affected individuals have a high level of a substance called lactate in the brain and elsewhere in the body. The severity of the condition varies. Mildly affected individuals usually develop signs and symptoms after the age of 6 months. Loss of mental and movement abilities (psychomotor regression), muscle stiffness (spasticity), and extreme irritability are common, and some people with mild LTBL develop seizures. However, after age 2, the signs and symptoms of the condition improve: affected children regain some psychomotor abilities, seizures are reduced or disappear, MRI results become more normal, and lactate levels drop. Severely affected individuals have features that begin soon after birth. These infants typically have delayed development of mental and movement abilities (psychomotor delay), weak muscle tone (hypotonia), involuntary muscle tensing (dystonia), muscle spasticity, and seizures. Some have extremely high levels of lactate (lactic acidosis), which can cause serious breathing problems and an abnormal heartbeat. Liver failure occurs in some severely affected infants. In severe cases, the signs and symptoms do not improve and can be life-threatening. In some people with LTBL, the features fall between mild and severe.","Curated_Disease_Description_Source__c":"GARD:0013381","GARD_Synonym__c":"combined oxidative phosphorylation defect type 12; combined oxidative phosphorylation deficiency 12; combined oxidative phosphorylation deficiency caused by mutation in ears2; combined oxidative phosphorylation deficiency type 12; coxpd12; coxpd12 - combined oxidative phosphorylation defect type 12; ears2 combined oxidative phosphorylation deficiency; leukoencephalopathy with thalamus and brainstem involvement and high lactate; leukoencephalopathy, thalamus and brainstem anomalies, high lactate syndrome; ltbl","Name":"Leukoencephalopathy-thalamus and brainstem anomalies-high lactate syndrome","estimateUsa":""}],"Organization_Supported_Diseases__c":[{"Account_Name__c":"CureARS","Website__c":"https://www.curears.org/"},{"Account_Name__c":"United Mitochondrial Disease Foundation","Website__c":"https://www.umdf.org"},{"Account_Name__c":"Alex The Leukodystrophy Charity","Website__c":"https://www.alextlc.org"}],"GARD_Disease_Tag__c":[{"Tag_Name__c":"Genetics","Tag_Category__c":"Cause;Disease Category;Specialist","category_description":"Genetic diseases affect the DNA, or genetic instructions, which directs how tissues, organs, and body systems function.","curated_tag_name":"Genetic diseases"},{"Tag_Name__c":"Neurology","Tag_Category__c":"Disease Category;Specialist","category_description":"Neurological diseases affect the brain, spinal cord, cranial nerves, autonomic nerves, or other peripheral nerves.","curated_tag_name":"Neurological diseases"},{"Tag_Name__c":"Inborn Errors of Metabolism","Tag_Category__c":"Cause;Disease Category","category_description":"Inherited metabolic diseases, or inborn errors of metabolism, are a group of genetic diseases that affect the ability of the body's cells to convert food into energy.","curated_tag_name":"Inherited metabolic diseases"},{"Tag_Name__c":"Mitochondrial","Tag_Category__c":"Account;Cause;Disease Category","category_description":"Mitochondrial diseases are a group of genetic diseases that affect the ability of the body's cells to make energy.","curated_tag_name":"Mitochondrial diseases"},{"Tag_Name__c":"Leukodystrophy","Tag_Category__c":"Account;Cause;Disease Category","category_description":"Leukodystrophies are a group of genetic neurological diseases that affect the white matter of the brain and spinal cord.","curated_tag_name":"Leukodystrophies"},{"Tag_Name__c":"Pediatrics","Tag_Category__c":"Specialist"}],"Age_At_Onset__c":[{"Age_At_Onset__c":"Neonatal","Provided_By__c":"ORPHA:314051"},{"Age_At_Onset__c":"Infancy","Provided_By__c":"ORPHA:314051"}],"Diagnosis__c":[{"Type__c":"GTR","Curie__c":"MEDGEN:C3554079"}],"External_Identifier_Disease__c":[{"URL__c":"https://browser.ihtsdotools.org/?perspective=full&conceptId1=763366000","Source__c":"C4706421; MONDO:0013971","Xref__c":"763366000"},{"URL__c":"https://www.ebi.ac.uk/ols4/ontologies/doid/classes?obo_id=DOID%3A0111493","Source__c":"MONDO:0013971","Xref__c":"DOID:0111493"},{"URL__c":"https://www.omim.org/entry/614924","Source__c":"C4706421; MONDO:0013971; ORPHA:314051","Xref__c":"OMIM:614924"},{"URL__c":"https://www.orpha.net/en/disease/detail/314051","Source__c":"C4706421; MONDO:0013971; ORPHA:314051","Xref__c":"ORPHA:314051"},{"URL__c":"https://www.ncbi.nlm.nih.gov/medgen/?term=1645614","Source__c":"C4706421","Xref__c":"MEDGEN:1645614"},{"URL__c":"https://uts.nlm.nih.gov/uts/umls/concept/C4706421","Source__c":"C4706421","Xref__c":"C4706421"},{"URL__c":"http://purl.obolibrary.org/obo/MONDO_0013971","Source__c":"GARD:0013381","Xref__c":"MONDO:0013971"},{"URL__c":"https://medlineplus.gov/genetics/condition/leukoencephalopathy-with-thalamus-and-brainstem-involvement-and-high-lactate","Source__c":"GARD:0013381","Xref__c":"https://medlineplus.gov/genetics/condition/leukoencephalopathy-with-thalamus-and-brainstem-involvement-and-high-lactate"}],"GARD_Disease_Gene__c":[{"GeneSymbol__c":"EARS2","GHR_URL__c":"https://medlineplus.gov/genetics/gene/ears2","Gene_Type__c":"protein-coding gene","Causal_Gene__c":true}],"Inheritance__c":["Autosomal recessive"],"GARD_Disease_Feature__c":[{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"An abnormal buildup of lactic acid in the body, leading to acidification of the blood and other bodily fluids.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0003128","HPO_Synonym__c":"Hyperlacticacidemia; Increased lactate in body; Lactic acidemia; Lacticacidemia; Lacticacidosis","HPO_Name__c":"Lactic acidosis","HPO_Feature_Type__c":"Lab"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"The concentration of aspartate aminotransferase (AST) in the blood circulation is above the upper limit of normal.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0031956","HPO_Synonym__c":"Aspartate aminotransferase increased; Elevated serum aspartate aminotransferase; Elevated serum AST; Elevated serum glutamic oxaloacetic transaminase","HPO_Name__c":"Elevated circulating aspartate aminotransferase concentration","HPO_Feature_Type__c":"Lab"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"Concentration of alpha-fetoprotein in the blood circulation above the upper limit of normal.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0006254","HPO_Synonym__c":"Increased levels of alpha fetoprotein; Increased serum alpha-fetoprotein; Serum alpha-fetoprotein increased","HPO_Name__c":"Elevated circulating alpha-fetoprotein concentration","HPO_Feature_Type__c":"Lab"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"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.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001252","HPO_Synonym__c":"Low muscle tone; Low or weak muscle tone; Muscle hypotonia; Muscular hypotonia","HPO_Name__c":"Hypotonia","Feature_System__c":"Musculoskeletal System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","Feature__r":{"HPO_Description__c":"An abnormally increased muscular tone that causes fixed abnormal postures. There is a slow, intermittent twisting motion that leads to exaggerated turning and posture of the extremities and trunk.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001332","HPO_Synonym__c":"Dystonic movements","HPO_Name__c":"Dystonia","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"Cleft palate is a developmental defect of the palate resulting from a failure of fusion of the palatine processes and manifesting as a separation of the roof of the mouth (soft and hard palate).","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000175","HPO_Synonym__c":"Cleft hard and soft palate; Cleft of hard and soft palate; Cleft of palate; Cleft palate; Cleft roof of mouth; Palatoschisis; Uranostaphyloschisis","HPO_Name__c":"Cleft palate","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","Feature__r":{"HPO_Description__c":"Paralysis of one or more extraocular muscles that are responsible for eye movements.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000602","HPO_Synonym__c":"Eye muscle paralysis; Paralysis of extraocular eye movement","HPO_Name__c":"Ophthalmoplegia","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Upturning of the big toe (and sometimes fanning of the other toes) in response to stimulation of the sole of the foot. If the Babinski sign is present it can indicate damage to the corticospinal tract.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0003487","HPO_Synonym__c":"Extensor plantar reflexes; Extensor plantar response; Extensor plantar responses; Positive Babinski sign","HPO_Name__c":"Babinski sign","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001250","HPO_Synonym__c":"Epileptic seizure; Seizures","HPO_Name__c":"Seizure","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Spastic weakness affecting all four limbs.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001285","HPO_Synonym__c":"Spastic quadriparesis","HPO_Name__c":"Spastic tetraparesis","Feature_System__c":"Nervous System; Musculoskeletal System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"A reduction in the activity of the mitochondrial respiratory chain complex III, which is part of the electron transport chain in mitochondria.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0011924","HPO_Name__c":"Decreased activity of mitochondrial complex III","HPO_Feature_Type__c":"Lab"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"Absence of the corpus callosum as a result of the failure of the corpus callosum to develop, which can be the result of a failure in any one of the multiple steps of callosal development including cellular proliferation and migration, axonal growth or glial patterning at the midline.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001274","HPO_Synonym__c":"Absence of corpus callosum; Absent corpus callosum; Agenesis of the corpus callosum; Callosal agenesis; Corpus callosum agenesis; Dysplastic or absent corpus callosum","HPO_Name__c":"Agenesis of corpus callosum","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","Feature__r":{"HPO_Description__c":"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.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0003200","HPO_Synonym__c":"Mitochondrial proliferation in muscle tissue; Ragged red muscle fibers; Ragged-red fibers","HPO_Name__c":"Ragged-red muscle fibers","Feature_System__c":"Musculoskeletal System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","Feature__r":{"HPO_Description__c":"Visual impairment (or vision impairment) is vision loss (of a person) to such a degree as to qualify as an additional support need through a significant limitation of visual capability resulting from either disease, trauma, or congenital or degenerative conditions that cannot be corrected by conventional means, such as refractive correction, medication, or surgery.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000505","HPO_Synonym__c":"Impaired vision; Loss of eyesight; Poor vision; Visual impairment","HPO_Name__c":"Visual impairment","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"Impaired ability to eat related to problems gathering food and getting ready to suck, chew, or swallow it.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0011968","HPO_Synonym__c":"Decreased oral intake; Feeding difficulties; Feeding problems; Poor feeding","HPO_Name__c":"Feeding difficulties","Feature_System__c":"Digestive System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Muscular hypotonia (abnormally low muscle tone) affecting the musculature of the trunk.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0008936","HPO_Synonym__c":"Low muscle tone in trunk; Muscular hypotonia of the trunk; Truncal hypotonia","HPO_Name__c":"Axial hypotonia","Feature_System__c":"Musculoskeletal System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"Impairment of bile flow due to obstruction in bile ducts.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001396","HPO_Synonym__c":"Slowed or blocked flow of bile from liver","HPO_Name__c":"Cholestasis","Feature_System__c":"Digestive System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"Difficulty to maintain correct position of the head while standing or sitting. Infant head lag is observed when the head seems to flop around or lags posteriorly behind the trunk. Several articles have maintained that head lag should be absent by age 3 to 4 months.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002421","HPO_Synonym__c":"Delay in head control; Delay in head righting; Infant head lag; Poor head control","HPO_Name__c":"Poor head control","Feature_System__c":"Musculoskeletal System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"Abnormally increased size of the liver.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002240","HPO_Synonym__c":"Enlarged liver","HPO_Name__c":"Hepatomegaly","Feature_System__c":"Digestive System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","Feature__r":{"HPO_Description__c":"Dysplasia and dysgenesis of the corpus callosum are nonspecific descriptions that imply defective development of the corpus callosum. The term dysplasia is applied when the morphology of the corpus callosum is altered as a congenital trait. For instance, the corpus callosum may be hump-shaped, kinked, or a striped corpus callosum that lacks an anatomically distinct genu and splenium.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0006989","HPO_Synonym__c":"Dysgenesis of corpus callosum; Dysplasia of corpus callosum","HPO_Name__c":"Dysplastic corpus callosum","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Underdevelopment of the corpus callosum.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002079","HPO_Synonym__c":"Corpus callosum hypoplasia; Hypoplasia of corpus callosum; Hypoplastic corpus callosum; Underdevelopment of part of brain called corpus callosum","HPO_Name__c":"Hypoplasia of the corpus callosum","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001263","HPO_Synonym__c":"Delayed cognitive development; Delayed development; Delayed developmental milestones; Delayed intellectual development; Delayed milestones; Delayed psychomotor development; Developmental delay; Developmental delay in early childhood; Developmental delay, global; Developmental retardation; GDD; Lack of psychomotor development; Motor and developmental delay; Motormental retardation; Psychomotor delay; Psychomotor development deficiency; Psychomotor development failure; Psychomotor developmental delay; Retarded development; Retarded mental development; Retarded psychomotor development","HPO_Name__c":"Global developmental delay","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"A reduction in the activity of the mitochondrial respiratory chain complex I, which is part of the electron transport chain in mitochondria.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0011923","HPO_Name__c":"Decreased activity of mitochondrial complex I","HPO_Feature_Type__c":"Lab"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"Loss of developmental skills, as manifested by loss of developmental milestones.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002376","HPO_Synonym__c":"Loss of acquired milestones; Loss of developmental milestones; Loss of milestones; Mental deterioration in childhood; Neurodevelopmental regression; Psychomotor regression; Psychomotor regression beginning in infancy; Psychomotor regression in infants; Psychomotor regression, progressive","HPO_Name__c":"Developmental regression","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","Feature__r":{"HPO_Description__c":"Muscular hypotonia (abnormally low muscle tone) manifesting in the neonatal period.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001319","HPO_Synonym__c":"Hypotonia, in neonatal onset; Hypotonia, neonatal; Low muscle tone, in neonatal onset","HPO_Name__c":"Neonatal hypotonia","Feature_System__c":"Musculoskeletal System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"A reduction in the activity of the mitochondrial respiratory chain complex IV, which is part of the electron transport chain in mitochondria.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0008347","HPO_Name__c":"Decreased activity of mitochondrial complex IV","HPO_Feature_Type__c":"Lab"}},{"Provided_By__c":"OMIM:614924","Feature__r":{"HPO_Description__c":"The upper eyelid margin is positioned 3 mm or more lower than usual and covers the superior portion of the iris (objective); or, the upper lid margin obscures at least part of the pupil (subjective).","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000508","HPO_Synonym__c":"Blepharoptosis; Drooping upper eyelid; Eyelid ptosis; Palpebral ptosis","HPO_Name__c":"Ptosis","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","Feature__r":{"HPO_Description__c":"This term describes abnormality of the white matter of the cerebrum resulting from damage to the myelin sheaths of nerve cells.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002352","HPO_Name__c":"Leukoencephalopathy","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"Delayed myelination in the central nervous system.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002188","HPO_Synonym__c":"Delay in central nervous system myelination","HPO_Name__c":"Delayed CNS myelination","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","Feature__r":{"HPO_Description__c":"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).","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002151","HPO_Synonym__c":"Increased blood lactate; Increased serum lactate","HPO_Name__c":"Increased circulating lactate concentration","HPO_Feature_Type__c":"Lab"}},{"Provided_By__c":"OMIM:614924","Feature__r":{"HPO_Description__c":"Failure to thrive (FTT) refers to a child whose physical growth is substantially below the norm.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001508","HPO_Synonym__c":"Faltering weight; FTT; Postnatal failure to thrive; Weight faltering","HPO_Name__c":"Failure to thrive","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"An abnormally high concentration in the circulation of alanine aminotransferase (ALT).","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0031964","HPO_Synonym__c":"Alanine aminotransferase increased; Elevated serum alanine aminotransferase; Elevated serum ALT; Elevated serum glutamic-pyruvic transaminase","HPO_Name__c":"Elevated circulating alanine aminotransferase concentration","HPO_Feature_Type__c":"Lab"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Complete lack of development of speech and language abilities.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001344","HPO_Synonym__c":"Absent speech development; Lack of language development; Lack of speech; No speech development; No speech or language development; Nonverbal","HPO_Name__c":"Absent speech","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"OMIM:614924","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"A form of hepatic steatosis characterized by the presence of large, lipid-laden vesicles in the affected hepatocytes.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001403","HPO_Synonym__c":"Macrovesicular steatosis","HPO_Name__c":"Macrovesicular hepatic steatosis","Feature_System__c":"Digestive System","HPO_Feature_Type__c":"Lab"}},{"Provided_By__c":"OMIM:614924","Feature__r":{"HPO_Description__c":"Bradykinesia literally means slow movement, and is used clinically to denote a slowness in the execution of movement (in contrast to hypokinesia, which is used to refer to slowness in the initiation of movement).","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002067","HPO_Synonym__c":"Slow movements; Slowness of movements","HPO_Name__c":"Bradykinesia","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}}],"tags":{"Cause":["Genetics","Inborn Errors of Metabolism","Mitochondrial","Leukodystrophy"],"Disease Category":["Genetics","Neurology","Inborn Errors of Metabolism","Mitochondrial","Leukodystrophy"],"Specialist":["Genetics","Neurology","Pediatrics"],"Account":["Mitochondrial","Leukodystrophy"]},"synonyms":["combined oxidative phosphorylation defect type 12"," combined oxidative phosphorylation deficiency 12"," combined oxidative phosphorylation deficiency caused by mutation in ears2"," combined oxidative phosphorylation deficiency type 12"," coxpd12"," coxpd12 - combined oxidative phosphorylation defect type 12"," ears2 combined oxidative phosphorylation deficiency"," leukoencephalopathy with thalamus and brainstem involvement and high lactate"," leukoencephalopathy, thalamus and brainstem anomalies, high lactate syndrome"," ltbl"]}