raremaprare-disease reference indexOrphadata 2026-06-23 · HPO 2026-09-01
ORPHA:1799

Familial developmental dysphasia

Synonyms: Billard-Toutain-Maheut syndrome · FOXP2-associated dysphasia

Type
Clinical syndrome
Group
Disorder
Inheritance
Autosomal dominant
Age of onset
Childhood
Status
active

Familial developmental dysphasia is a severe form of developmental verbal apraxia characterized by a deficit in spontaneous speech, writing, grammatical judgment and repetition, defective articulation, moderate to severe degree of dyspraxia, a reduced use of consonant clusters, and comprehension delay. Hearing and intelligence are normal.

1

Names in Orphadata languages

12 of 12 languages
LangNameSynonyms
enFamilial developmental dysphasiaBillard-Toutain-Maheut syndrome · FOXP2-associated dysphasia
frDysphasie congénitale familialeDysphasie associée à FOXP2 · Syndrome de Billard-Toutain-Maheut
deDysphasie, familiäre kongenitaleBillard-Toutain-Maheut-Syndrom · Sprachentwicklung, familiäre verzögerte
esDisfasia congénita familiarSíndrome de Billard-Toutain-Maheut
itDisfasia congenita familiareDisfasia associata a FOXP2 · Sindrome di Billard-Toutain-Maheut
nlFamiliale ontwikkelingsdysfasieFOXP2-geassocieerde dysfasie · Syndroom van Billard-Toutain-Maheut
ptDisfasia do desenvolvimento familiarSíndrome Billard-Toutain-Maheut
plRodzinna dysfazja rozwojowaDysfazja związana z FOXP2 · Zespół Billarda, Toutaina i Maheuta
csFamiliární vývojová dysfázieFOXP2 asociovaná dysfázie · Billardův-Toutainův-Maheutův syndrom · Billard-Toutain-Maheutův syndrom
ukСімейна дисфазія розвиткуСиндром Білларда-Тутена-Магеута · FOXP2-асоційована дисфазія
zh家族性发育性语言障碍Billard-Toutain-Maheut综合征
trAilesel gelişimsel disfaziFOXP2-ilişkili disfazi · Billard-Toutain-Maheut sendromu

Definition in:

2

Cross-references

qualifier = Orphanet mapping relation
SourceCodeQualifierICD relationValidation
OMIM600117Evalidated
ICD-10F80.1NTBTattributedvalidated
MONDO0010821Evalidated
MeSHC563997Evalidated
UMLSC1838630Evalidated
GARD1823Evalidated

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

3

Classification

Preferential parent (Orphanet linearisation):

Parents in the classifications (1):

No children.

4

Genes

0 direct

Orphanet records no gene directly on this code.

5

Prevalence and incidence

2 records
TypeClassValueAreaQualificationValidationSource
Cases/families6 familiesWorldwideFamily(ies)Validated8031532[PMID]
Point prevalence<1 / 1 000 000—WorldwideClass onlyValidatedORPHANET_8031532[PMID]

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

6

HPO phenotypes

3 annotations · validated 2016-06-01
HPOTerm (as annotated by Orphanet)Diagnostic
Very frequent (99-80%)
HP:0002381Aphasia
HP:0002474Expressive language delay
HP:0002546Incomprehensible speech

Run the differential on the 3 obligate / very frequent terms

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Sources for this card