{"Name":"3-hydroxyisobutyryl-CoA hydrolase deficiency","DiseaseID__c":"GARD:0013202","id":13202,"encodedName":"3-hydroxyisobutyryl-coa-hydrolase-deficiency","IsDeleted":false,"Disease_Name_Full__c":"3-hydroxyisobutyryl-CoA hydrolase deficiency","Xref_IDs__c":"722488009; C0342738; C562803; DOID:0060949; MEDGEN:83349; MONDO:0009603; OMIM:250620; ORPHA:88639","USA_Estimate__c":"1,000","No_of_Specialist_Tagsa__c":4,"No_of_ClinGen_records__c":0,"No_of_GeneReviews__c":0,"No_of_HHS_records__c":0,"World_Estimate__c":"1 to 8,000","No_of_HRSA_records__c":0,"Evidence_Based_Score__c":0,"No_of_Disease_Descriptions__c":4,"Disease_Characteristics_Score__c":7,"No_of_Age_at_Onset__c":1,"Description_Source__c":"MONDO:0009603","Disease_Description__c":"Neurodegeneration due to 3-hydroxyisobutyryl-CoA hydrolase deficiency is characterised by delayed motor development, hypotonia and progressive neurodegeneration. To date, it has been described in four boys. The syndrome is caused by mutations affecting the two alleles of the <i> HIBCH</i> gene, encoding 3-hydroxyisobutyryl-CoA hydrolase. The mode of transmission has not yet been established.","GARD_Name__c":"3-hydroxyisobutyryl-CoA hydrolase deficiency","GARD_Synonym__c":"3-hydroxyisobutryl-coa hydrolase deficiency; beta-hydroxyisobutyryl-coenzyme a deacylase deficiency; deficiency of 3-hydroxyisobutyryl coa hydrolase; deficiency of 3-hydroxyisobutyryl coenzyme a hydrolase; hibch deficiency; methacrylic acid toxicity; methacrylic aciduria; neurodegeneration due to 3-hydroxyisobutyryl-coa hydrolase deficiency; reduced circulating 3-hydroxyisobutyryl-coa hydrolase activity; valine metabolic defect","Curated_Disease_Description_Source__c":"GARD:0013202","Curated_Disease_Description__c":"Neurodegeneration due to 3-hydroxyisobutyryl-CoA hydrolase deficiency, also known as HIBCH deficiency, is a rare metabolic disease. Early symptoms include poor muscle tone, poor feeding, seizures, and a gradual loss of skills. HIBCH deficiency can cause signs and symptoms similar to another disease, called Leigh syndrome. Diagnosis is aided by blood tests which show high levels of lactic acid, and imaging studies which show changes in the \"\"globi pallidi\"\" structure of the brain. HIBCH deficiency occurs when a person inherits a genetic change in both copies of their HIBCH gene. This pattern of inheritance is called \"\"autosomal recessive.\"\" The HIBCH gene tells the body how to make an enzyme called 3-hyroxyisobutyryl-CoA hydrolase. When the body does not have enough working enzyme, it can not break down the amino acid valine. As a result, toxic valine metabolites build up in the body. More specifically, these toxic metabolites build up within the mitochondria of the body's cells.","Curated_USA_Estimate_Source__c":null,"Curated_USA_Estimate__c":"1,000","Age_at_Onset_Snippet_Text__c":"as an Infant","SourceID__c":"ORPHA:88639","Deprecated__c":"No","Disease_Concept_Type__c":"Rare Disease Entity","MONDO_ID__c":"MONDO:0009603","ORPHANET_ID__c":"ORPHA:88639","Replaced_By_ID__c":null,"Display_Spanish_Disease_Name__c":"Neurodegeneración por deficiencia en 3-hidroxisobutiril-coa-hidrolasa","Spanish_Description_Source__c":"ORPHA:88639","Spanish_Description__c":"Es un trastorno caracterizado por retraso del desarrollo motor, hipotonía y neurodegeneración progresiva. Hasta la fecha, se ha descrito en cuatro niños. El síndrome está causado por mutaciones que afectan a los dos alelos del gen <i>HIBCH</i>, que codifica para la 3-hidroxiisobutiril-CoA hidrolasa. El modo de transmisión aún no ha sido establecido.","Spanish_Disease_Name__c":"neurodegeneración por deficiencia en 3-hidroxisobutiril-coa-hidrolasa","Spanish_GARD_Synonym__c":"aciduria metacrílica; defecto metabólico de la valina; deficiencia de hibch","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":"Neurodegeneration due to 3-hydroxyisobutyryl-CoA hydrolase deficiency, also known as HIBCH deficiency, is a rare metabolic disease. Early symptoms include poor muscle tone, poor feeding, seizures, and a gradual loss of skills. HIBCH deficiency can cause signs and symptoms similar to another disease, called Leigh syndrome. Diagnosis is aided by blood tests which show high levels of lactic acid, and imaging studies which show changes in the \"\"globi pallidi\"\" structure of the brain. HIBCH deficiency occurs when a person inherits a genetic change in both copies of their HIBCH gene. This pattern of inheritance is called \"\"autosomal recessive.\"\" The HIBCH gene tells the body how to make an enzyme called 3-hyroxyisobutyryl-CoA hydrolase. When the body does not have enough working enzyme, it can not break down the amino acid valine. As a result, toxic valine metabolites build up in the body. More specifically, these toxic metabolites build up within the mitochondria of the body's cells.","Curated_Disease_Description_Source__c":"GARD:0013202","GARD_Synonym__c":"3-hydroxyisobutryl-coa hydrolase deficiency; beta-hydroxyisobutyryl-coenzyme a deacylase deficiency; deficiency of 3-hydroxyisobutyryl coa hydrolase; deficiency of 3-hydroxyisobutyryl coenzyme a hydrolase; hibch deficiency; methacrylic acid toxicity; methacrylic aciduria; neurodegeneration due to 3-hydroxyisobutyryl-coa hydrolase deficiency; reduced circulating 3-hydroxyisobutyryl-coa hydrolase activity; valine metabolic defect","Name":"3-hydroxyisobutyryl-CoA hydrolase deficiency","Curated_USA_Estimate__c":"1,000","estimateUsa":"1,000"}],"Organization_Supported_Diseases__c":[{"Account_Name__c":"Childhood Dementia Initiative","Website__c":"https://www.childhooddementia.org/"},{"Account_Name__c":"Metabolic Support UK","Website__c":"https://www.metabolicsupportuk.org"},{"Account_Name__c":"United Mitochondrial Disease Foundation","Website__c":"https://www.umdf.org"},{"Account_Name__c":"Organic Acidemia Association","Website__c":"https://oaanews.org/"},{"Account_Name__c":"MitoAction","Website__c":"https://www.mitoaction.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":"Neurodevelopmental disabilities","Tag_Category__c":"Specialist","curated_tag_name":"Neurodevelopmental disabilities"},{"Tag_Name__c":"Pediatrics","Tag_Category__c":"Specialist"}],"Age_At_Onset__c":[{"Age_At_Onset__c":"Infancy","Provided_By__c":"ORPHA:88639"}],"External_Identifier_Disease__c":[{"URL__c":"https://raresource.nih.gov/diseases/filter/0013202","Source__c":"RareSource"},{"URL__c":"https://www.omim.org/entry/250620","Source__c":"C0342738; MONDO:0009603; ORPHA:88639","Xref__c":"OMIM:250620"},{"URL__c":"https://www.ncbi.nlm.nih.gov/medgen/?term=83349","Source__c":"C0342738","Xref__c":"MEDGEN:83349"},{"URL__c":"https://browser.ihtsdotools.org/?perspective=full&conceptId1=722488009","Source__c":"MONDO:0009603","Xref__c":"722488009"},{"URL__c":"https://www.orpha.net/en/disease/detail/88639","Source__c":"C0342738; MONDO:0009603; ORPHA:88639","Xref__c":"ORPHA:88639"},{"URL__c":"https://uts.nlm.nih.gov/uts/umls/concept/C0342738","Source__c":"C0342738","Xref__c":"C0342738"},{"URL__c":"https://www.ebi.ac.uk/ols4/ontologies/doid/classes?obo_id=DOID%3A0060949","Source__c":"MONDO:0009603","Xref__c":"DOID:0060949"},{"URL__c":"https://www.ncbi.nlm.nih.gov/mesh/C562803","Source__c":"MONDO:0009603","Xref__c":"C562803"},{"URL__c":"http://purl.obolibrary.org/obo/MONDO_0009603","Source__c":"GARD:0013202","Xref__c":"MONDO:0009603"},{"URL__c":"https://browser.ihtsdotools.org/?perspective=full&conceptId1=124427009","Source__c":"C0342738","Xref__c":"124427009"},{"URL__c":"https://hpo.jax.org/browse/term/HP:6000215","Source__c":"C0342738","Xref__c":"HP:6000215"},{"URL__c":"https://www.ncbi.nlm.nih.gov/books/NBK619246/","Source__c":"Gene Review","Xref__c":"NBK619246"}],"GARD_Disease_Gene__c":[{"GeneSymbol__c":"HIBCH","Gene_Type__c":"protein-coding gene","Causal_Gene__c":true}],"Inheritance__c":["Autosomal recessive"],"GARD_Disease_Feature__c":[{"Provided_By__c":"ORPHA:88639","HPO_Frequency__c":"Occasional (5-29%)","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":"ORPHA:88639","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"An abnormality of one or more of the vertebrae.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0003468","HPO_Synonym__c":"Abnormal vertebrae; Abnormality of the vertebrae; Vertebral anomalies","HPO_Name__c":"Abnormal vertebral morphology","Feature_System__c":"Musculoskeletal System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:88639","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002093","HPO_Synonym__c":"Respiratory impairment","HPO_Name__c":"Respiratory insufficiency","Feature_System__c":"Respiratory system","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:88639","HPO_Frequency__c":"Very frequent (80-99%)","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":"ORPHA:88639","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"Forceful ejection of the contents of the stomach through the mouth by means of a series of involuntary spasmic contractions.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002013","HPO_Synonym__c":"Emesis; Throwing up; Vomiting","HPO_Name__c":"Vomiting","Feature_System__c":"Digestive System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:88639","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002344","HPO_Synonym__c":"Neurologic deterioration; Neurologic deterioration, progressive; Progressive mental deterioration; Progressive neurodegeneration; Worsening neurological symptoms","HPO_Name__c":"Progressive neurologic deterioration","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:88639","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"A type of Developmental delay characterized by a delay in acquiring motor skills.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001270","HPO_Synonym__c":"Delay in development of motor milestones; Delay in motor development; Delayed development of motor milestones; Delayed early motor milestones; Delayed motor development; Delayed motor milestones; Locomotor delay; Motor developmental delay; Motor developmental milestones not achieved; Motor retardation; Retarded motor development; Slow development of motor milestones","HPO_Name__c":"Motor delay","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:88639","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"A misalignment of the eyes so that the visual axes deviate from bifoveal fixation. The classification of strabismus may be based on a number of features including the relative position of the eyes, whether the deviation is latent or manifest, intermittent or constant, concomitant or otherwise and according to the age of onset and the relevance of any associated refractive error.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000486","HPO_Synonym__c":"Cross-eyed; Squint; Squint eyes","HPO_Name__c":"Strabismus","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:88639","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Hyperreflexia is the presence of hyperactive stretch reflexes of the muscles.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001347","HPO_Synonym__c":"Increased deep tendon reflexes; Increased reflexes","HPO_Name__c":"Hyperreflexia","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:88639","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0011334","HPO_Synonym__c":"Facial shape compression; Facial shape deformation","HPO_Name__c":"Facial shape deformation","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:88639","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"An abnormal pattern in the quality, quantity, or characteristics of sleep.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002360","HPO_Synonym__c":"Difficulty sleeping; Sleep abnormality; Sleep disturbances; Sleep dysfunction; Sleep-wake disturbance; Trouble sleeping","HPO_Name__c":"Sleep disturbance","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:88639","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":"ORPHA:88639","HPO_Frequency__c":"Uncommon (<1-4%)","Feature__r":{"HPO_Description__c":"A head tremor of moderate speed (3 to 4 Hz) in the anterior-posterior direction.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002599","HPO_Name__c":"Head titubation","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:88639","HPO_Frequency__c":"Frequent (30-79%)","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":"ORPHA:88639","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"A functional anomaly of mitochondria.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0003287","HPO_Synonym__c":"Mitochondrial dysfunction","HPO_Name__c":"Abnormality of mitochondrial metabolism","HPO_Feature_Type__c":"Lab"}},{"Provided_By__c":"ORPHA:88639","HPO_Frequency__c":"Uncommon (<1-4%)","Feature__r":{"HPO_Description__c":"A congenital cardiac malformation comprising pulmonary stenosis, overriding aorta, ventricular septum defect, and right ventricular hypertrophy. The diagnosis of TOF is made if at least three of the four above mentioned features are present.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001636","HPO_Synonym__c":"Tetrology of fallot","HPO_Name__c":"Tetralogy of Fallot","Feature_System__c":"Cardiovascular System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:88639","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":"ORPHA:88639","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Truncal ataxia is a sign of ataxia characterized by instability of the trunk. It usually occurs during sitting.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002078","HPO_Synonym__c":"Instability or lack of coordination of central trunk muscles; Trunk ataxia","HPO_Name__c":"Truncal ataxia","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:88639","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Metabolic acidosis (MA) is characterized by a fall in blood pH due to a reduction of serum bicarbonate concentration. This can occur as a result of either the accumulation of acids (high anion gap MA) or the loss of bicarbonate from the gastrointestinal tract or the kidney (hyperchloremic MA). By definition, MA is not due to a respirary cause.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001942","HPO_Name__c":"Metabolic acidosis","HPO_Feature_Type__c":"Lab"}},{"Provided_By__c":"ORPHA:88639","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"Encephalopathy is a term that means brain disease, damage, or malfunction. 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Infantile Spasms are epileptic spasms starting in the first year of life (infancy).","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0012469","HPO_Name__c":"Infantile spasms","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:88639","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"A fold of skin starting above the medial aspect of the upper eyelid and arching downward to cover, pass in front of and lateral to the medial canthus.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000286","HPO_Synonym__c":"Epicanthal fold; Epicanthal folds; Epicanthic folds; Eye folds; Palpebronasal fold; Plica palpebronasalis; Prominent eye folds","HPO_Name__c":"Epicanthus","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:88639","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Absence or underdevelopment of the corpus callosum.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0007370","HPO_Synonym__c":"Absent/hypoplastic corpus callosum; Agenesis/hypoplastic corpus callosum; Complete or partial absence of the corpus callosum; Hypoplasia or absence of the corpus callosum; Hypoplastic or absent corpus callosum","HPO_Name__c":"Aplasia/Hypoplasia of the corpus callosum","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:88639","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"An emotional state characterized by negative feelings of heightened frustration, annoyance, or feeling upset, often triggered by internal factors (e.g., fatigue, hunger, unfulfilled desires) or external factors (e.g., social or environmental challenges). Irritability may be unpredictable, and is accompanied by a lowered threshold for emotional reactivity and observable features (speech, facial expressions, or psychomotor activity).","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000737","HPO_Synonym__c":"Cranky; Easily annoyed; Easily bothered; Easily upset; Grumpy; Hot-temper; Irritability; Irritable; Irritable mood; On edge; Quick-temper; Short fuse; Short tempered","HPO_Name__c":"Irritability","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:88639","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"Decreased size of the basal ganglia.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0012697","HPO_Name__c":"Small basal ganglia","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:88639","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Hypsarrhythmia is abnormal interictal high amplitude waves and a background of irregular spikes. There is continuous (during wakefulness), high-amplitude (>200 Hz), generalized polymorphic slowing with no organized background and multifocal spikes demonstrated by electroencephalography (EEG).","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002521","HPO_Synonym__c":"Hypsarrhythmia by EEG","HPO_Name__c":"Hypsarrhythmia","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Procedure_EEG"}}],"tags":{"Cause":["Genetics","Inborn Errors of Metabolism"],"Disease Category":["Genetics","Neurology","Inborn Errors of Metabolism"],"Specialist":["Genetics","Neurology","Neurodevelopmental disabilities","Pediatrics"]},"synonyms":["3-hydroxyisobutryl-coa hydrolase deficiency"," beta-hydroxyisobutyryl-coenzyme a deacylase deficiency"," deficiency of 3-hydroxyisobutyryl coa hydrolase"," deficiency of 3-hydroxyisobutyryl coenzyme a hydrolase"," hibch deficiency"," methacrylic acid toxicity"," methacrylic aciduria"," neurodegeneration due to 3-hydroxyisobutyryl-coa hydrolase deficiency"," reduced circulating 3-hydroxyisobutyryl-coa hydrolase activity"," valine metabolic defect"]}