raremaprare-disease reference indexOrphadata 2026-06-23 · HPO 2026-09-01
ORPHA:3197

Hereditary hyperekplexia

Synonyms: Congenital stiff man syndrome · Familial startle disease · Hereditary hyperexplexia · Kok disease · Stiff baby syndrome

Type
Disease
Group
Disorder
Inheritance
Autosomal dominant, Autosomal recessive
Age of onset
Infancy, Neonatal
Status
active

Hereditary hyperekplexia is a hereditary neurological disorder characterized by excessive startle responses.

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Names in Orphadata languages

12 of 12 languages
LangNameSynonyms
enHereditary hyperekplexiaCongenital stiff man syndrome · Familial startle disease · Hereditary hyperexplexia · Kok disease · Stiff baby syndrome
frHyperexplexie héréditaireHyperekplexie · Hyperekplexie héréditaire · Maladie de Kok · Maladie familiale du sursaut · Syndrome "stiff baby" · Syndrome "stiff man" congénital
deHyperekplexie, hereditäreKok-Krankheit · Startle-Krankheit, familiäre · Stiff-Baby-Syndrom · Stiff-Man-Syndrom, kongenitales
esHiperekplexia hereditariaHiperplexia hereditaria · Síndrome congénito del hombre rígido · Síndrome del bebé rígido · Enfermedad de Kok · Enfermedad del sobresalto familiar · Hiperecplexia hereditaria
itIperekplexia ereditariaIperekplexia · Iperexplexia ereditaria · Malattia dei sussulti familiare · Malattia di Kok · Sindrome congenita dell'uomo rigido · Sindrome del neonato rigido
nlErfelijke hyperekplexieCongenitaal stiff man-syndroom · Congenitaal stijve man-syndroom · Familiale schrikziekte · Hereditaire hyperekplexie · Stiff baby-syndroom · Stijve baby-syndroom · Ziekte van Kok
ptHiperecplexia hereditáriaDoença "startle" familiar · Doença de Kok · Hiperecplexia hereditária · Síndrome bebé rígido · Síndrome homem rígido congénito
plHiperekpleksja dziedzicznaChoroba Koka · Familial startle disease · Hiperekpleksja · Hiperekpleksja dziedziczna · Wrodzony zespół sztywności uogólnionej · Zespół sztywnego dziecka
csDefekt glycinového receptoruVrozený syndrom celkového ztuhnutí · Familiární choroba s úlekovými reakcemi · Hereditární hyperekplexie · Kokova nemoc
ukСпадкова гіперекплексіяСиндром вродженої скутості людини · Родинна хвороба тремтіння · Спадкова гіперчутливість · Хвороба Кок · Синдром скованого немовляти
zh遗传性肌张力过度先天性僵人综合征
trKalıtsal hiperekpleksiKok hastalığı · Katı bebek sendromu · Ailesel irkilme hastalığı · Kalıtsal hiperekspleksi · Doğumsal katı adam sendromu

Definition in:

2

Cross-references

qualifier = Orphanet mapping relation
SourceCodeQualifierICD relationValidation
OMIM149400Evalidated
OMIM614618BTNTvalidated
OMIM614619BTNTvalidated
OMIM618011BTNTvalidated
ICD-10G25.8NTBTattributedvalidated
ICD-11LD90.YNTBTindexvalidated
MONDO0021022Evalidated
MeSHC538136Evalidated
UMLSC1835614Evalidated
GARD3129Evalidated

E exact · NTBT this ORPHAcode is narrower than the target · BTNT broader than the target · ND not decided.

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Classification

Preferential parent (Orphanet linearisation):

Parents in the classifications (6):

No children.

Codes that Orphanet moved or referred to this one:

4

Genes

5 direct
GeneAssociationStatusHGNCEnsemblOMIMLocusNameSource of validation
ATAD1Disease-causing germline mutation(s) inAssessedHGNC:25903ENSG0000013813861445210q23.31ATPase family AAA domain containing 129390050[PMID]
GLRA1Disease-causing germline mutation(s) inAssessedHGNC:4326ENSG000001458881384915q33.1glycine receptor alpha 120301437[PMID]
GLRBDisease-causing germline mutation(s) inAssessedHGNC:4329ENSG000001097381384924q32.1glycine receptor beta20301437[PMID]
GPHNDisease-causing germline mutation(s) inAssessedHGNC:15465ENSG0000017172360393014q23.3gephyrin20301437[PMID]
SLC6A5Disease-causing germline mutation(s) inAssessedHGNC:11051ENSG0000016597060415911p15.1solute carrier family 6 member 520301437[PMID]
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Prevalence and incidence

2 records
TypeClassValueAreaQualificationValidationSource
Cases/families150 casesWorldwideCase(s)ValidatedORPHANET
Point prevalence<1 / 1 000 000—WorldwideClass onlyValidatedORPHANET

Value is Orphadata's ValMoy: the mean estimate per 100 000 for prevalence and incidence, the number of cases or families for case reports.

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HPO phenotypes

21 annotations · validated 2017-10-10
HPOTerm (as annotated by Orphanet)Diagnostic
Very frequent (99-80%)
HP:0100022Abnormality of movement
HP:0001251Ataxia
HP:0100633Esophagitis
HP:0002380Fasciculations
HP:0002020Gastroesophageal reflux
HP:0002036Hiatus hernia
HP:0001347Hyperreflexia
HP:0001276Hypertonia
HP:0001387Joint stiffness
HP:0003552Muscle stiffness
HP:0001336Myoclonus
HP:0002063Rigidity
HP:0001257Spasticity
Frequent (79-30%)
HP:0001288Gait disturbance
HP:0100790Hernia
HP:0002360Sleep abnormality
HP:0001537Umbilical hernia
Occasional (29-5%)
HP:0002827Hip dislocation
HP:0001249Intellectual disability
HP:0001373Joint dislocation
HP:0001250Seizure

Run the differential on the 12 obligate / very frequent terms

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Sources for this card