{"Name":"Megalencephalic leukoencephalopathy with subcortical cysts","DiseaseID__c":"GARD:0003445","id":3445,"encodedName":"megalencephalic-leukoencephalopathy-with-subcortical-cysts","IsDeleted":false,"Disease_Name_Full__c":"Megalencephalic leukoencephalopathy with subcortical cysts","Xref_IDs__c":"703536004; C1858854; C536141; DOID:0080315; MEDGEN:347006; MONDO:0011391; NBK1535; ORPHA:2478","USA_Estimate__c":"1,000","No_of_Specialist_Tagsa__c":3,"No_of_ClinGen_records__c":0,"No_of_GeneReviews__c":1,"No_of_HHS_records__c":1,"World_Estimate__c":"1 to 8,000","No_of_HRSA_records__c":0,"Evidence_Based_Score__c":3,"No_of_Disease_Descriptions__c":4,"Disease_Characteristics_Score__c":8,"No_of_Age_at_Onset__c":2,"Description_Source__c":"MONDO:0011391","Disease_Description__c":"A form of leukodystrophy that is characterized by infantile-onset macrocephaly, often with mild neurologic signs at presentation (such as mild motor delay), which worsen with time, leading to poor ambulation, falls, ataxia, spasticity, increasing seizures and cognitive decline. Brain magnetic resonance imaging reveals diffusely abnormal and mildly swollen white matter as well as subcortical cysts in the anterior temporal and frontoparietal regions.","GARD_Name__c":"Megalencephalic leukoencephalopathy with subcortical cysts","GARD_Synonym__c":"infantile leukoencephalopathy and megalencephaly; leukoencephalopathy with swelling and cysts; megalencephalic leukodystrophy; megalencephalic leukoencephalopathy with subcortical cysts type 1; megalencephaly-cystic leukodystrophy syndrome; mlc; vacuolating leukoencephalopathy; vacuolating megalencephalic leukoencephalopathy with subcortical cysts; van der knaap disease; van der knaap syndrome; van der knapp disease","Curated_Disease_Description_Source__c":"GARD:0003445","Curated_Disease_Description__c":"Megalencephalic leukoencephalopathy with subcortical cysts is a progressive condition that affects brain development and function. Individuals with this condition typically have an enlarged brain (megalencephaly) that is evident at birth or within the first year of life. Megalencephaly leads to an increase in the size of the head (macrocephaly). Affected people also have leukoencephalopathy, an abnormality of the brain's white matter. White matter consists of nerve fibers covered by a fatty substance called myelin. Myelin insulates nerve cells (neurons) and promotes the rapid transmission of nerve impulses. In megalencephalic leukoencephalopathy with subcortical cysts, the myelin is swollen and contains numerous fluid-filled pockets (vacuoles). Over time, the swelling decreases and the myelin begins to waste away (atrophy). Individuals affected with this condition may develop cysts in the brain; because these cysts form below an area of the brain called the cerebral cortex, they are called subcortical cysts. These cysts can grow in size and number. The brain abnormalities in people with megalencephalic leukoencephalopathy with subcortical cysts affect the use of muscles and lead to movement problems. Affected individuals typically experience muscle stiffness (spasticity) and difficulty coordinating movements (ataxia). Walking ability varies greatly among those affected. Some people lose the ability to walk early in life and need wheelchair assistance, while others are able to walk unassisted well into adulthood. Minor head trauma can further impair movements and may lead to coma. Affected individuals may also develop uncontrolled muscle tensing (dystonia), involuntary writhing movements of the limbs (athetosis), difficulty swallowing (dysphagia), and impaired speech (dysarthria). More than half of all people with this condition have recurrent seizures (epilepsy). Despite the widespread brain abnormalities, people with this condition typically have only mild to moderate intellectual disability. There are three types of megalencephalic leukoencephalopathy with subcortical cysts, which are distinguished by their signs and symptoms and genetic cause. Types 1 and 2A have different genetic causes but are nearly identical in signs and symptoms. Types 2A and 2B have the same genetic cause but the signs and symptoms of type 2B often begin to improve after one year. After improvement, individuals with type 2B usually have macrocephaly and may have intellectual disability.","Curated_USA_Estimate_Source__c":null,"Curated_USA_Estimate__c":"1,000","Age_at_Onset_Snippet_Text__c":"as a Newborn and as an Infant","SourceID__c":"ORPHA:2478","Deprecated__c":"No","Disease_Concept_Type__c":"Rare Disease Grouping","MONDO_ID__c":"MONDO:0011391","ORPHANET_ID__c":"ORPHA:2478","Replaced_By_ID__c":null,"Display_Spanish_Disease_Name__c":"Leucoencefalopatía megalencefálica con quistes subcorticales","Spanish_Description_Source__c":"ORPHA:2478","Spanish_Description__c":"Es una forma de leucodistrofia que se caracteriza por una macrocefalia de aparición en la infancia, a menudo con síntomas neurológicos leves a la presentación (tales como retraso motor leve), que empeoran con el tiempo, conduciendo a trastorno de la marcha, caídas, ataxia, espasticidad, convulsiones de frecuencia e intensidad crecientes y deterioro cognitivo. Las imágenes de resonancia magnética cerebrales muestran una afectación difusa y ligera inflamación de la sustancia blanca así como quistes subcorticales en las regiones temporal anterior y frontoparietal.","Spanish_Disease_Name__c":"leucoencefalopatía megalencefálica con quistes subcorticales","Spanish_GARD_Synonym__c":"leucodistrofia megalencefálica; leucoencefalopatía megalencefálica vacuolizante con quistes subcorticales; megalencefalia-leucodistrofia quística; mlc; síndrome de van der knapp","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":"Megalencephalic leukoencephalopathy with subcortical cysts is a progressive condition that affects brain development and function. Individuals with this condition typically have an enlarged brain (megalencephaly) that is evident at birth or within the first year of life. Megalencephaly leads to an increase in the size of the head (macrocephaly). Affected people also have leukoencephalopathy, an abnormality of the brain's white matter. White matter consists of nerve fibers covered by a fatty substance called myelin. Myelin insulates nerve cells (neurons) and promotes the rapid transmission of nerve impulses. In megalencephalic leukoencephalopathy with subcortical cysts, the myelin is swollen and contains numerous fluid-filled pockets (vacuoles). Over time, the swelling decreases and the myelin begins to waste away (atrophy). Individuals affected with this condition may develop cysts in the brain; because these cysts form below an area of the brain called the cerebral cortex, they are called subcortical cysts. These cysts can grow in size and number. The brain abnormalities in people with megalencephalic leukoencephalopathy with subcortical cysts affect the use of muscles and lead to movement problems. Affected individuals typically experience muscle stiffness (spasticity) and difficulty coordinating movements (ataxia). Walking ability varies greatly among those affected. Some people lose the ability to walk early in life and need wheelchair assistance, while others are able to walk unassisted well into adulthood. Minor head trauma can further impair movements and may lead to coma. Affected individuals may also develop uncontrolled muscle tensing (dystonia), involuntary writhing movements of the limbs (athetosis), difficulty swallowing (dysphagia), and impaired speech (dysarthria). More than half of all people with this condition have recurrent seizures (epilepsy). Despite the widespread brain abnormalities, people with this condition typically have only mild to moderate intellectual disability. There are three types of megalencephalic leukoencephalopathy with subcortical cysts, which are distinguished by their signs and symptoms and genetic cause. Types 1 and 2A have different genetic causes but are nearly identical in signs and symptoms. Types 2A and 2B have the same genetic cause but the signs and symptoms of type 2B often begin to improve after one year. After improvement, individuals with type 2B usually have macrocephaly and may have intellectual disability.","Curated_Disease_Description_Source__c":"GARD:0003445","GARD_Synonym__c":"infantile leukoencephalopathy and megalencephaly; leukoencephalopathy with swelling and cysts; megalencephalic leukodystrophy; megalencephalic leukoencephalopathy with subcortical cysts type 1; megalencephaly-cystic leukodystrophy syndrome; mlc; vacuolating leukoencephalopathy; vacuolating megalencephalic leukoencephalopathy with subcortical cysts; van der knaap disease; van der knaap syndrome; van der knapp disease","Name":"Megalencephalic leukoencephalopathy with subcortical cysts","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":"United Leukodystrophy Foundation","Website__c":"https://ulf.org/"},{"Account_Name__c":"Leukodystrophy Australia","Website__c":"https://www.leuko.org.au/"},{"Account_Name__c":"The Myelin Project","Website__c":"http://www.myelin.org"},{"Account_Name__c":"Association Européenne contre les Leucodystrophies (ELA)","Website__c":"http://www.ela-asso.com"},{"Account_Name__c":"Alex The Leukodystrophy Charity","Website__c":"https://www.alextlc.org"},{"Account_Name__c":"Hunter's Hope Foundation","Website__c":"https://www.huntershope.org/"},{"Account_Name__c":"The Stop ALD Foundation","Website__c":"https://www.stopald.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":"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:2478"},{"Age_At_Onset__c":"Infancy","Provided_By__c":"ORPHA:2478"}],"Diagnosis__c":[{"Type__c":"GTR","Curie__c":"MEDGEN:C1858854"}],"External_Identifier_Disease__c":[{"URL__c":"https://raresource.nih.gov/diseases/filter/0003445","Source__c":"RareSource"},{"URL__c":"https://www.ncbi.nlm.nih.gov/books/NBK1535","Source__c":"Gene Review","Xref__c":"NBK1535"},{"URL__c":"https://www.ncbi.nlm.nih.gov/mesh/C536141","Source__c":"MONDO:0011391","Xref__c":"C536141"},{"URL__c":"https://www.ebi.ac.uk/ols4/ontologies/doid/classes?obo_id=DOID%3A0080315","Source__c":"MONDO:0011391","Xref__c":"DOID:0080315"},{"URL__c":"https://uts.nlm.nih.gov/uts/umls/concept/C1858854","Source__c":"C1858854","Xref__c":"C1858854"},{"URL__c":"https://www.orpha.net/en/disease/detail/2478","Source__c":"C1858854; MONDO:0011391; ORPHA:2478","Xref__c":"ORPHA:2478"},{"URL__c":"https://www.ncbi.nlm.nih.gov/medgen/?term=347006","Source__c":"C1858854","Xref__c":"MEDGEN:347006"},{"URL__c":"https://browser.ihtsdotools.org/?perspective=full&conceptId1=703536004","Source__c":"C1858854; MONDO:0011391","Xref__c":"703536004"},{"URL__c":"https://medlineplus.gov/genetics/condition/megalencephalic-leukoencephalopathy-with-subcortical-cysts","Source__c":"GARD:0003445","Xref__c":"https://medlineplus.gov/genetics/condition/megalencephalic-leukoencephalopathy-with-subcortical-cysts"},{"URL__c":"http://purl.obolibrary.org/obo/MONDO_0011391","Source__c":"GARD:0003445","Xref__c":"MONDO:0011391"}],"GARD_Disease_Gene__c":[{"GeneSymbol__c":"MLC1","GHR_URL__c":"https://medlineplus.gov/genetics/gene/mlc1","Gene_Type__c":"protein-coding gene","Causal_Gene__c":true},{"GeneSymbol__c":"HEPACAM","GHR_URL__c":"https://medlineplus.gov/genetics/gene/hepacam","Gene_Type__c":"protein-coding gene","Causal_Gene__c":true}],"Inheritance__c":["Autosomal recessive","Autosomal dominant"],"GARD_Disease_Feature__c":[{"Provided_By__c":"ORPHA:2478","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"The postnatal development of an abnormally large skull (macrocephaly).","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0005490","HPO_Synonym__c":"Macrocephaly, postnatal","HPO_Name__c":"Postnatal macrocephaly","Feature_System__c":"Musculoskeletal System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:2478","HPO_Frequency__c":"Occasional (5-29%)","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:2478","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"A motor disorder characterized by a velocity-dependent increase in tonic stretch reflexes with increased muscle tone, exaggerated (hyperexcitable) tendon reflexes.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001257","HPO_Synonym__c":"Involuntary muscle stiffness, contraction, or spasm; Muscle spasticity; Muscular spasticity","HPO_Name__c":"Spasticity","Feature_System__c":"Nervous System; Musculoskeletal System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:2478","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0007341","HPO_Name__c":"Diffuse swelling of cerebral white matter","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:2478","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Ataxia refers to impaired coordination of voluntary muscle movement. Cerebellar ataxia refers to ataxia due to dysfunction of the cerebellum. This causes a variety of elementary neurological deficits including asynergy (lack of coordination between muscles, limbs and joints), dysmetria (lack of ability to judge distances that can lead to under- or overshoot in grasping movements), and dysdiadochokinesia (inability to perform rapid movements requiring antagonizing muscle groups to be switched on and off repeatedly).","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001251","HPO_Synonym__c":"Cerebellar ataxia","HPO_Name__c":"Ataxia","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:2478","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"A fluid-filled sac (cyst) in the region below the cortex of the cerebrum. In magnetic resonance imaging, the fluid within the cyst has the same appearance as cerebrospinal fluid (CSF).","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:6000461","HPO_Name__c":"Cerebral subcortical cyst","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:2478","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"Lack of physical coordination resulting in an abnormal tendency to drop items or bump into objects.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002312","HPO_Synonym__c":"Clumsiness","HPO_Name__c":"Clumsiness","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:2478","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Atypical behavior is an abnormality in a person's actions that can be controlled or modulated by the will of the individual. While abnormal behaviors can be difficult to control, they are distinct from other abnormal actions that cannot be affected by the individual's will.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000708","HPO_Synonym__c":"Behavioral abnormality; Behavioral changes; Behavioral disorders; Behavioral disturbances; Behavioral problems; Behavioral symptoms; Behavioral/psychiatric abnormalities; Behavioural symptoms; Behavioural/Psychiatric abnormality; Psychiatric disorders; Psychiatric disturbances","HPO_Name__c":"Atypical behavior","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:2478","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"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.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001249","HPO_Synonym__c":"Intellectual disability; Mental deficiency; Mental retardation; Mental retardation, nonspecific; Mental-retardation; Nonprogressive intellectual disability; Nonprogressive mental retardation","HPO_Name__c":"Intellectual disability","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:2478","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"Status epilepticus is a type of prolonged seizure resulting either from the failure of the mechanisms responsible for seizure termination or from the initiation of mechanisms which lead to abnormally prolonged seizures (after time point t1). It is a condition that can have long-term consequences (after time point t2), including neuronal death, neuronal injury, and alteration of neuronal networks, depending on the type and duration of seizures.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002133","HPO_Synonym__c":"Prolonged seizure; Repeated seizure without recovery; Repeated seizures without recovery between them","HPO_Name__c":"Status epilepticus","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:2478","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002317","HPO_Synonym__c":"Gait instability; Unsteady walk","HPO_Name__c":"Unsteady gait","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:2478","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Loss of previously present mental abilities, generally in adults.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0001268","HPO_Synonym__c":"Cognitive decline; Cognitive decline, progressive; Intellectual deterioration; Mental deterioration; Progressive cognitive decline","HPO_Name__c":"Mental deterioration","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:2478","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"A slow, continuous, involuntary writhing movement that prevents maintenance of a stable posture. Athetosis involves continuous smooth movements that appear random and are not composed of recognizable sub-movements or movement fragments. In contrast to chorea, in athetosis, the same regions of the body are repeatedly involved. Athetosis may worsen with attempts at movement of posture, but athetosis can also occur at rest.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002305","HPO_Synonym__c":"Athetoid movements; Involuntary writhing movements; Involuntary writhing movements in fingers, hands, toes, and feet","HPO_Name__c":"Athetosis","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:2478","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:2478","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"The presence of atrophy (wasting) of the cerebral white matter.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0012762","HPO_Name__c":"Cerebral white matter atrophy","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:2478","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"Autism is a neurodevelopmental disorder characterized by impaired social interaction and communication, and by restricted and repetitive behavior. Autism begins in childhood. It is marked by the presence of markedly abnormal or impaired development in social interaction and communication and a markedly restricted repertoire of activity and interest. Manifestations of the disorder vary greatly depending on the developmental level and chronological age of the individual (DSM-IV).","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0000717","HPO_Synonym__c":"Autism","HPO_Name__c":"Autism","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:2478","HPO_Frequency__c":"Occasional (5-29%)","Feature__r":{"HPO_Description__c":"A neurological condition related to lesions of the basal ganglia leading to typical abnormalities including akinesia (inability to initiate changes in activity and perform volitional movements rapidly and easily), muscular rigidity (continuous contraction of muscles with constant resistance to passive movement), chorea (widespread arrhythmic movements of a forcible, rapid, jerky, and restless nature), athetosis (inability to sustain the muscles of the fingers, toes, or other group of muscles in a fixed position), and akathisia (inability to remain motionless).","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002071","HPO_Synonym__c":"Extrapyramidal dysfunction; Extrapyramidal signs; Extrapyramidal symptoms; Extrapyramidal syndrome; Extrapyramidal tract signs","HPO_Name__c":"Abnormality of extrapyramidal motor function","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}},{"Provided_By__c":"ORPHA:2478","HPO_Frequency__c":"Frequent (30-79%)","Feature__r":{"HPO_Description__c":"Loss of previously present motor (i.e., movement) abilities.","HPO_Feature_URL__c":"https://hpo.jax.org/browse/term/HP:0002333","HPO_Synonym__c":"Progressive degeneration of movement","HPO_Name__c":"Motor deterioration","Feature_System__c":"Nervous System","HPO_Feature_Type__c":"Symptom"}}],"tags":{"Cause":["Genetics","Leukodystrophy"],"Disease Category":["Genetics","Neurology","Leukodystrophy"],"Specialist":["Genetics","Neurology","Pediatrics"],"Account":["Leukodystrophy"]},"synonyms":["infantile leukoencephalopathy and megalencephaly"," leukoencephalopathy with swelling and cysts"," megalencephalic leukodystrophy"," megalencephalic leukoencephalopathy with subcortical cysts type 1"," megalencephaly-cystic leukodystrophy syndrome"," mlc"," vacuolating leukoencephalopathy"," vacuolating megalencephalic leukoencephalopathy with subcortical cysts"," van der knaap disease"," van der knaap syndrome"," van der knapp disease"]}