{"Name":"Tay-Sachs disease, variant AB","DiseaseID__c":"GARD:0017406","id":17406,"encodedName":"tay-sachs-disease-variant-ab","IsDeleted":false,"Disease_Name_Full__c":"Tay-Sachs disease, variant AB","Xref_IDs__c":"71253000; C0268275; C133084; D049290; DOID:4795; MEDGEN:78657; MONDO:0010099; OMIM:272750; ORPHA:309246","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":1,"World_Estimate__c":"1 to 8,000","No_of_HRSA_records__c":0,"Evidence_Based_Score__c":1,"No_of_Disease_Descriptions__c":4,"Disease_Characteristics_Score__c":8,"No_of_Age_at_Onset__c":1,"Description_Source__c":"MONDO:0010099","Disease_Description__c":"GM2 gangliosidosis, AB variant is an extremely rare, severe genetic disorder characterized by progressive neurological decline due to ganglioside activator deficiency.","GARD_Name__c":"Tay-Sachs disease, variant AB","GARD_Synonym__c":"ab variant; gm>2< gangliosidosis, type ab; gm2 activator deficiency; gm2 gangliosidosis, ab variant; gm2-gangliosidosis, ab variant; hexosaminidase activator deficiency; tay-sachs disease ab variant","Curated_Disease_Description_Source__c":"PlainLanguagePilotV2-Jan24","Curated_Disease_Description__c":"GM2 activator deficiency (sometimes called GM2 gangliosidosis, AB variant) is a rare inherited disorder that causes progressive brain injury.    Most individuals with GM2 activator deficiency have the acute infantile form of the disease.  Signs and symptoms of acute infantile GM2 activator deficiency typically appear between the ages of 4 and 12 months, when development slows and the muscles used for movement weaken. Infants with acute infantile GM2 activator deficiency stop achieving normal developmental milestones and eventually lose previously acquired skills such as turning over, sitting, and crawling. These infants also develop an exaggerated startle reaction to loud noises. Over time, infants with acute infantile GM2 activator deficiency typically experience seizures, vision loss, and intellectual disabilites. They eventually become unable to respond to their environment. An eye abnormality called a cherry-red spot, which can be identified with an eye examination, is characteristic of the infantile form of this disorder. Infants with acute infantile GM2 activator deficiency may survive into early childhood. Some people with GM2 activator deficiency  may develop milder and more variable signs and symptoms later in life. Due to the rarity of this condition, the full spectrum of the late-onset presentation has not been clearly defined.","Curated_USA_Estimate_Source__c":null,"Curated_USA_Estimate__c":"1,000","Age_at_Onset_Snippet_Text__c":"as an Infant","SourceID__c":"ORPHA:309246","Deprecated__c":"No","Disease_Concept_Type__c":"Rare Disease Entity","MONDO_ID__c":"MONDO:0010099","ORPHANET_ID__c":"ORPHA:309246","Replaced_By_ID__c":null,"Display_Spanish_Disease_Name__c":"Gangliosidosis gm2, variante ab","Spanish_Description_Source__c":"ORPHA:309246","Spanish_Description__c":"Es un trastorno genético grave y extremadamente poco frecuente caracterizado por un deterioro neurológico progresivo debido a un déficit del activador de gangliósidos.","Spanish_Disease_Name__c":"gangliosidosis gm2, variante ab","Spanish_GARD_Synonym__c":"deficiencia del activador de hexosaminidasa","Category_Linearization__c":"ORPHA:68367","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":"GM2 activator deficiency (sometimes called GM2 gangliosidosis, AB variant) is a rare inherited disorder that causes progressive brain injury.    Most individuals with GM2 activator deficiency have the acute infantile form of the disease.  Signs and symptoms of acute infantile GM2 activator deficiency typically appear between the ages of 4 and 12 months, when development slows and the muscles used for movement weaken. Infants with acute infantile GM2 activator deficiency stop achieving normal developmental milestones and eventually lose previously acquired skills such as turning over, sitting, and crawling. These infants also develop an exaggerated startle reaction to loud noises. Over time, infants with acute infantile GM2 activator deficiency typically experience seizures, vision loss, and intellectual disabilites. They eventually become unable to respond to their environment. An eye abnormality called a cherry-red spot, which can be identified with an eye examination, is characteristic of the infantile form of this disorder. Infants with acute infantile GM2 activator deficiency may survive into early childhood. Some people with GM2 activator deficiency  may develop milder and more variable signs and symptoms later in life. Due to the rarity of this condition, the full spectrum of the late-onset presentation has not been clearly defined.","Curated_Disease_Description_Source__c":"PlainLanguagePilotV2-Jan24","GARD_Synonym__c":"ab variant; gm>2< gangliosidosis, type ab; gm2 activator deficiency; gm2 gangliosidosis, ab variant; gm2-gangliosidosis, ab variant; hexosaminidase activator deficiency; tay-sachs disease ab variant","Name":"Tay-Sachs disease, variant AB","Curated_USA_Estimate__c":"1,000","estimateUsa":"1,000"}],"Organization_Supported_Diseases__c":[{"Account_Name__c":"National Tay-Sachs and Allied Diseases Association","Website__c":"https://www.ntsad.org/"},{"Account_Name__c":"Alex The Leukodystrophy Charity","Website__c":"https://www.alextlc.org"},{"Account_Name__c":"United Leukodystrophy Foundation","Website__c":"https://ulf.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":"Lysosomal","Tag_Category__c":"Account;Cause;Disease Category","category_description":"Lysosomal storage diseases are a group of genetic metabolic diseases that affect the ability of the body's cells to break down substances and remove toxins.","curated_tag_name":"Lysosomal storage diseases"},{"Tag_Name__c":"Epilepsy","Tag_Category__c":"Account;Specialist","curated_tag_name":"Epilepsy"},{"Tag_Name__c":"Pediatrics","Tag_Category__c":"Specialist"}],"Age_At_Onset__c":[{"Age_At_Onset__c":"Infancy","Provided_By__c":"ORPHA:309246"}],"External_Identifier_Disease__c":[{"URL__c":"https://www.ncbi.nlm.nih.gov/books/NBK583219","Source__c":"Gene Review","Xref__c":"NBK583219"},{"URL__c":"https://www.ncbi.nlm.nih.gov/mesh/C049290","Source__c":"C0268275; MONDO:0010099","Xref__c":"D049290"},{"URL__c":"https://www.orpha.net/en/disease/detail/309246","Source__c":"C0268275; MONDO:0010099; ORPHA:309246","Xref__c":"ORPHA:309246"},{"URL__c":"https://uts.nlm.nih.gov/uts/umls/concept/C0268275","Source__c":"C0268275","Xref__c":"C0268275"},{"URL__c":"https://www.omim.org/entry/272750","Source__c":"C0268275; MONDO:0010099; ORPHA:309246","Xref__c":"OMIM:272750"},{"URL__c":"https://browser.ihtsdotools.org/?perspective=full&conceptId1=71253000","Source__c":"C0268275; MONDO:0010099","Xref__c":"71253000"},{"URL__c":"https://www.ncbi.nlm.nih.gov/medgen/?term=78657","Source__c":"C0268275","Xref__c":"MEDGEN:78657"},{"URL__c":"https://evsexplore.semantics.cancer.gov/evsexplore/concept/ncit/C133084","Source__c":"C0268275; MONDO:0010099","Xref__c":"C133084"},{"URL__c":"https://www.ebi.ac.uk/ols4/ontologies/doid/classes?obo_id=DOID%3A4795","Source__c":"MONDO:0010099","Xref__c":"DOID:4795"},{"URL__c":"http://purl.obolibrary.org/obo/MONDO_0010099","Source__c":"GARD:0017406","Xref__c":"MONDO:0010099"},{"URL__c":"https://medlineplus.gov/genetics/condition/gm2-activator-deficiency","Source__c":"GARD:0017406","Xref__c":"https://medlineplus.gov/genetics/condition/gm2-activator-deficiency"}],"GARD_Disease_Gene__c":[{"GeneSymbol__c":"GM2A","GHR_URL__c":"https://medlineplus.gov/genetics/gene/gm2a","Gene_Type__c":"protein-coding gene","Causal_Gene__c":true}],"Inheritance__c":["Autosomal recessive"],"GARD_Disease_Feature__c":[{"Provided_By__c":"ORPHA:309246","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Slow or limited growth after birth.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0008897","HPO_Synonym__c":"Growth delay as children; Growth retardation as children; Postnatal growth deceleration; Postnatal growth deficiency; Postnatal growth failure","HPO_Name__c":"Postnatal growth retardation","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Anomalous movements of the eyes that occur without the subject wanting them to happen.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0012547","HPO_Name__c":"Abnormal involuntary eye movements","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","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":"ORPHA:309246","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"An abnormal fear-induced behavior includes observable actions. This behavior is characterized by abnormal responses to fear or abnormal fear levels. Examples of such behavior include avoiding fear-inducing situations.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0100852","HPO_Synonym__c":"Abnormal fear-induced behavior; Abnormal fear/anxiety-related behavior","HPO_Name__c":"Abnormal fear-induced behavior","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","HPO_Frequency__c":"Very frequent (80-99%)","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:309246","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"Progressive loss of neural cells and tissue.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002180","HPO_Synonym__c":"Ongoing loss of nerve cells","HPO_Name__c":"Neurodegeneration","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","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:309246","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Pallor of the perifoveal macula of the retina with appearance of a small circular reddish choroid shape as seen through the fovea centralis due to relative transparency of the macula.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0010729","HPO_Synonym__c":"Macular cherry red spot","HPO_Name__c":"Cherry red spot of the macula","Feature_System__c":"Cardiovascular System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"An exaggerated startle reaction in response to a sudden unexpected visual or acoustic stimulus, or a quick movement near the face.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002267","HPO_Synonym__c":"Exaggerated acoustic startle response; Increased startle response","HPO_Name__c":"Exaggerated startle response","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"An explicit or perceived action, demonstration, conduct, or language (verbal and written) that is contrary to generally accepted norms, rules, procedures, or unacceptable within the context in which it is carried out. Inappropriate behaviors could take place in a sexual or social context and could be aggressive, violent, impulsive, intimidating, or threatening in nature.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000719","HPO_Synonym__c":"Inappropriate behavior","HPO_Name__c":"Inappropriate behavior","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"Abnormal cognition is characterized by deficits in thinking, reasoning, or remembering.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0100543","HPO_Synonym__c":"Abnormality of cognition; Cognitive abnormality; Cognitive defects; Cognitive deficits; Cognitive impairment; Intellectual impairment","HPO_Name__c":"Cognitive impairment","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"A type of primitive reflex that is elicited by repetitive tapping on the forehead. Normal subjects usually blink in response to the first several taps, but if blinking persists, the response is abnormal and considered to be a sign of frontal release. Persistent blinking is also known as Myerson's sign.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0030904","HPO_Name__c":"Glabellar reflex","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"Multiple pointlike areas of high T2 signal observed upon magnetic resonance imaging of the periventricular cerebral white matter.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0030081","HPO_Name__c":"Punctate periventricular T2 hyperintense foci","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Imaging_MRI"}},{"Provided_By__c":"ORPHA:309246","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"The primitive reflexes are a group of behavioral motor responses which are found in normal early development, are subsequently inhibited, but may be released from inhibition by cerebral, usually frontal, damage. They are thus part of a broader group of reflexes which reflect release phenomena, such as exaggerated stretch reflexes and extensor plantars. They do however involve more complex motor responses than such simple stretch reflexes, and are often a normal feature in the neonate or infant.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002476","HPO_Synonym__c":"Archaic reflex; Primitive reflexes","HPO_Name__c":"Primitive reflex","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"Functional neurological abnormalities related to dysfunction of the pyramidal tract.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0007256","HPO_Synonym__c":"Corticospinal signs; Pyramidal signs; Pyramidal tract signs","HPO_Name__c":"Abnormal pyramidal sign","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","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:309246","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"Pseudobulbar signs result from injury to an upper motor neuron lesion to the corticobulbar pathways in the pyramidal tract. Patients have difficulty chewing, swallowing and demonstrate slurred speech (often initial presentation) as well as abnormal behavioral symptoms such as inappropriate emotional outbursts of uncontrolled laughter or weeping etc.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002200","HPO_Synonym__c":"Pseudobulbar symptoms","HPO_Name__c":"Pseudobulbar signs","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"A height below that which is expected according to age and sex norms. Although there is no universally accepted definition of short stature, many refer to \\\"short stature\\\" as height more than 2 standard deviations below the mean for age and sex (or below the 3rd percentile for age and sex dependent norms).","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0004322","HPO_Synonym__c":"Decreased body height; Height less than 3rd percentile; Short stature; Small stature; Stature below 3rd percentile","HPO_Name__c":"Short stature","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"Over-sensitivity to certain frequency ranges of sound.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0010780","HPO_Name__c":"Hyperacusis","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Intense feelings of nervousness, tension, or panic often arise in response to interpersonal stresses. There is worry about the negative effects of past unpleasant experiences and future negative possibilities. Individuals may feel fearful, apprehensive, or threatened by uncertainty, and they may also have fears of falling apart or losing control.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000739","HPO_Synonym__c":"Anxiety; Anxiousness; Excessive, persistent worry and fear","HPO_Name__c":"Anxiety","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002371","HPO_Synonym__c":"Loss of speech","HPO_Name__c":"Loss of speech","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002478","HPO_Synonym__c":"Progressive spastic quadriparesis","HPO_Name__c":"Progressive spastic quadriplegia","Feature_System__c":"Nervous System; Musculoskeletal System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","HPO_Frequency__c":"Very frequent (80-99%)","Feature__r":{"HPO_Description__c":"Atrophy (wasting, decrease in size of cells or tissue) affecting the cerebrum.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002059","HPO_Synonym__c":"Degeneration of cerebrum","HPO_Name__c":"Cerebral atrophy","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Chorea (Greek for 'dance') refers to widespread arrhythmic involuntary movements of a forcible, jerky and restless fashion. It is a random-appearing sequence of one or more discrete involuntary movements or movement fragments. Movements appear random because of variability in timing, duration or location. Each movement may have a distinct start and end. However, movements may be strung together and thus may appear to flow randomly from one muscle group to another. Chorea can involve the trunk, neck, face, tongue, and extremities.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002072","HPO_Synonym__c":"Choreic movements; Choreiform movements","HPO_Name__c":"Chorea","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:309246","HPO_Frequency__c":"Very frequent (80-99%)","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"}}],"tags":{"Cause":["Genetics","Inborn Errors of Metabolism","Lysosomal"],"Disease Category":["Genetics","Neurology","Inborn Errors of Metabolism","Lysosomal"],"Specialist":["Genetics","Neurology","Epilepsy","Pediatrics"],"Account":["Lysosomal","Epilepsy"]},"synonyms":["ab variant"," gm>2< gangliosidosis, type ab"," gm2 activator deficiency"," gm2 gangliosidosis, ab variant"," gm2-gangliosidosis, ab variant"," hexosaminidase activator deficiency"," tay-sachs disease ab variant"]}