{"orpha":599376,"name":"Hypomyelination of early myelinating structures","type":"Disease","group":"Disorder","status":"active","flags":[],"synonyms":["HEMS"],"definition":"A rare genetic neurological disorder characterized by hypomyelination of early myelinating structures such as the brainstem, cerebellar white matter, optic radiation, and periventricular white matter, while structures acquiring myelin later are better myelinated. Patients present in infancy with nystagmus, developmental delay, and progressive ataxic-spastic or ataxic syndrome. Cognitive functions are normal or only mildly impaired.","note":null,"url":"https://raremap.alftech.space/d/ORPHA-599376/","orphanet_url":"https://www.orpha.net/en/disease/detail/599376","names":{"fr":{"name":"Hypomyélinisation des structures myélinisantes précoces","synonyms":["HEMS"],"definition":"Maladie neurologique génétique rare caractérisée par une hypomyélinisation des structures myélinisantes précoces, telles que le tronc cérébral, la substance blanche cérébelleuse, la radiation optique et la substance blanche périventriculaire, alors que les structures qui acquièrent la myéline plus tard sont mieux myélinisées. Pendant la petite enfance, les patients présentent un nystagmus, un retard de développement et un syndrome d'ataxie spastique progressif ou un syndrome d'ataxie progressif. Les fonctions cognitives sont normales ou seulement légèrement atteintes."},"de":{"name":"Hypomyelinisierung der früh myelinisierenden Strukturen","definition":"Eine seltene genetisch bedingte neurologische Erkrankung, die durch Hypomyelinisierung früher myelinisierender Strukturen wie Hirnstamm, weiße Substanz des Kleinhirns, Radiatio optica und periventrikuläre weiße Substanz gekennzeichnet ist, während Strukturen, die später Myelin erwerben, besser myelinisiert sind. Die Patienten zeigen im Säuglingsalter Nystagmus, Entwicklungsverzögerung und progressives ataxisch-spastisches oder ataxisches Syndrom. Die kognitiven Funktionen sind normal oder nur leicht beeinträchtigt."},"es":{"name":"Hipomielinización de estructuras milelinizadas a temprana edad","synonyms":["HEMS"],"definition":"Es un trastorno neurológico poco frecuente de origen genético caracterizado por hipomielinización de áreas de mielinización temprana, como el tronco encefálico, la sustancia blanca cerebelosa, las radiaciones ópticas y la sustancia blanca periventricular, mientras que las estructuras de mielinización tardía están mejor mielinizadas. Los pacientes se presentan en el periodo de lactancia con nistagmo, retraso del desarrollo y síndrome atáxico-espástico o atáxico progresivo. Las funciones cognitivas son normales o están ligeramente afectadas."},"it":{"name":"Ipomielinizzazione delle strutture a mielinizzazione precoce","synonyms":["HEMS"]},"nl":{"name":"Hypomyelinisatie van vroeg myeliniserende structuren","synonyms":["HEMS"],"definition":"Een zeldzame, genetische neurologische aandoening, gekenmerkt door hypomyelinisatie van vroeg gemyeliniseerde structuren zoals hersenstam, cerebellaire witte stof, radiatio optica, en periventriculaire witte stof, terwijl structuren die later myeline verwerven beter worden gemyeliniseerd. Patiënten presenteren zich in de zuigelingentijd met nystagmus, ontwikkelingsachterstand, en progressief atactisch-spastisch of atactisch syndroom. Cognitieve functies zijn normaal of slechts mild verstoord."},"pt":{"name":"Hipomielinização de estruturas mielizadas precocemente","synonyms":["HEMS"],"definition":"Doença neurológica genética rara caracterizada por hipomielinização de estruturas que mielinizam mais precocemente, como o tronco cerebral, a substância branca cerebelosa, as radiações óticas e a substância branca periventricular, enquanto as estruturas que adquirem mielina mais tarde são melhor mielinizadas. Os doentes apresentam-se na infância com nistagmo, atraso no desenvolvimento e síndrome atáxico-espástica ou atáxica progressiva. As funções cognitivas são normais ou apenas ligeiramente alteradas."},"pl":{"name":"Hipomielinizacja struktur z wczesnym wytwarzaniem mieliny","synonyms":["HEMS"],"definition":"Rzadkie genetyczne zaburzenie neurologiczne charakteryzujące się hipomielinizacją struktur ulegających wczesnej mielinizacji, takich jak pień mózgu, istota biała móżdżku, promienistość wzrokowa i okołokomorowa istota biała, podczas gdy struktury, które uległy mielinizacji później są lepiej zmielinizowane. Choroba objawia się w wieku niemowlęcym oczopląsem, opóźnieniem rozwoju i postępującym zespołem ataktyczno-spastycznym lub ataksją. Funkcje poznawcze są prawidłowe lub tylko nieznacznie zaburzone."},"cs":{"name":"Hypomyelinizace časných myelinizovaných struktur","synonyms":["HEMS"]},"uk":{"name":"Гіпомієлінізація ранніх мієлінізуючих структур","synonyms":["HEMS"],"definition":"A rare genetic neurological disorder characterized by hypomyelination of early myelinating structures such as the brainstem, cerebellar white matter, optic radiation, and periventricular white matter, while structures acquiring myelin later are better myelinated. Patients present in infancy with nystagmus, developmental delay, and progressive ataxic-spastic or ataxic syndrome. Cognitive functions are normal or only mildly impaired."},"zh":{"name":"Hypomyelination of early myelinating structures","synonyms":["HEMS"]},"tr":{"name":"Hypomyelination of early myelinating structures","synonyms":["HEMS"]}},"xrefs":[{"source":"ICD-10","code":"G37.8","qualifier":"NTBT","icd_relation":"attributed","validated":true},{"source":"MONDO","code":"0035398","qualifier":"E","icd_relation":null,"validated":true},{"source":"UMLS","code":"C5680278","qualifier":"E","icd_relation":null,"validated":true}],"associations":[],"incoming_associations":[],"preferential_parent":{"orpha":98006,"name":"Rare neurologic disease"},"parents":[{"orpha":183518,"name":"Hereditary ataxia","classifications":[156,181]},{"orpha":68356,"name":"Leukodystrophy","classifications":[156,181]},{"orpha":611314,"name":"Rare syndromic intellectual disability without multiple congenital anomalies/dysmorphic syndrome","classifications":[156,181]}],"children":[],"genes":[{"symbol":"PLP1","name":"proteolipid protein 1","gene_type":"gene with protein product","association":"Disease-causing germline mutation(s) in","status":"Assessed","source":"26125040[PMID]","hgnc":"9086","ensembl":"ENSG00000123560","omim":"300401","loci":["Xq22.2"]}],"genes_via_subtypes":[],"inheritance":["X-linked dominant"],"onset":["Infancy"],"prevalence":[{"type":"Cases/families","qualification":"Case(s)","class":null,"value":20.0,"area":"Worldwide","status":"Validated","source":"26125040[PMID]_33450882[PMID]"},{"type":"Point prevalence","qualification":"Class only","class":"<1 / 1 000 000","value":0.0,"area":"Worldwide","status":"Validated","source":"26125040[PMID]_33450882[PMID]_ORPHANET"}],"phenotypes":null}