raremaprare-disease reference indexOrphadata 2026-06-23 · HPO 2026-09-01
ORPHA:468726

Severe primary trimethylaminuria

Synonyms: TMAU

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

A rare inborn error of metabolism characterized by the presence of large amounts of trimethylamine in urine, sweat, and breath, resulting in a fishy body odor in affected individuals. While there are no additional signs and symptoms, the condition can have profound psychosocial consequences.

1

Names in Orphadata languages

12 of 12 languages
LangNameSynonyms
enSevere primary trimethylaminuriaTMAU
frTriméthylaminurie sévère primaire
deTrimethylaminurie, primäre schwere
esTrimetilaminuria primaria grave
itTrimetilaminuria primaria grave
nlErnstige primaire trimethylaminurie
ptTrimetilaminuria grave primária
plCiężka pierwotna trimetylaminuria= en
csTěžká primární trimetylaminurie= en
ukТяжка первинна триметиламінурія= en
zh严重的原发性三甲基尿症= en
trAğır primer trimetilaminüri= en

Definition in:

2

Cross-references

qualifier = Orphanet mapping relation
SourceCodeQualifierICD relationValidation
OMIM602079NTBTvalidated
ICD-10E88.8NTBTattributedvalidated
ICD-115C50.GNTBTattributedvalidated
MONDO0018767Evalidated
UMLSC5575503Evalidated
GARD6447Evalidated

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

1 direct
GeneAssociationStatusHGNCEnsemblOMIMLocusNameSource of validation
FMO3Disease-causing germline mutation(s) (loss of function) inAssessedHGNC:3771ENSG000000079331361321q24.3flavin containing dimethylaniline monoxygenase 320301282[PMID]_19321370[PMID]
5

Prevalence and incidence

1 record
TypeClassValueAreaQualificationValidationSource
Point prevalenceUnknown—WorldwideClass onlyValidatedORPHANET_25335494[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

10 annotations · validated 2021-05-28
HPOTerm (as annotated by Orphanet)Diagnostic
Obligate (100%)
HP:0410020Fish odor
Very frequent (99-80%)
HP:0003614Trimethylaminuria
Frequent (79-30%)
HP:0000712Emotional lability
HP:0031469Low self esteem
HP:0031467Negative affectivity
Occasional (29-5%)
HP:0000718Aggressive behavior
HP:0000739Anxiety
HP:0000716Depression
HP:0008770Obsessive-compulsive trait
HP:0011999Paranoia

Run the differential on the 2 obligate / very frequent terms

Annotation source: 20301282[PMID]_33473342[PMID]

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Sources for this card