raremaprare-disease reference indexOrphadata 2026-06-23 · HPO 2026-09-01
ORPHA:3434

MMEP syndrome

Synonyms: MCOPS8 · Microcephaly-microphthalmia-ectrodactyly of lower limbs-prognathism syndrome · Syndromic microphthalmia type 8 · Viljoen-Smart syndrome

Type
Malformation syndrome
Group
Disorder
Age of onset
Antenatal, Neonatal
Status
active

The MMEP syndrome is a congenital syndromic form of split-hand/foot malformation (SHFM). It is characterized by microcephaly, microphthalmia, ectrodactyly of the lower limbs and prognathism. Intellectual deficit has been reported. MMEP syndrome is considered to be a very rare condition, although the exact prevalence remains unknown. The etiology is not completely understood. Disruption of the sorting nexin 3 gene (<i>SNX3</i>; 6q21) has been shown to play a causative role in MMEP, although this was not confirmed in recent studies.

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Names in Orphadata languages

12 of 12 languages
LangNameSynonyms
enMMEP syndromeMCOPS8 · Microcephaly-microphthalmia-ectrodactyly of lower limbs-prognathism syndrome · Syndromic microphthalmia type 8 · Viljoen-Smart syndrome
frSyndrome MMEPMCOPS8 · Microphtalmie syndromique type 8 · Syndrome de Viljoen-Smart · Syndrome de microcéphalie-microphtalmie-ectrodactylie des membres inférieurs-prognathisme
deMMEP-SyndromMCOPS8 · Microcephaly - Mikrophthalmie - Ektrodaktylie der unteren Extremitäten - Prognathie · Mikrophthalmie, syndromale, Typ 8 · Viljoen-Smart-Syndrom
esSíndrome MMEPMicrocefalia-microftalmia-ectrodactilia de extremidades inferiores-prognatismo · Microftalmia sindrómica tipo 8 · Síndrome de Viljoen-Smart
itSindrome MMEPMCOPS8 · Microcefalia - microftalmia - ectrodattilia degli arti inferiori - prognatismo · Microftalmia sindromica, tipo 8 · Sindrome di Viljoen-Smart
nlMMEP-syndroomMCOPS8 · Microcefalie - microftalmie - ectrodactylie van onderste ledematen - prognathie-syndroom · Syndromale microftalmie type 8 · Syndroom van Viljoen-Smart
ptSíndrome MMEPMCOPS8 · Microftalmia sindrómica tipo 8 · Síndrome Viljoen-Smart · Síndrome de microcefalia-microftalmia-ectrodactilia dos membros inferiores-prognatismo
plZespół MMEPMałogłowie - małoocze - ektrodaktylia kończyn dolnych - prognatyzm · MCOPS8 · Syndromiczne małoocze typu 8 8 · Zespół Viljoena i Smarta
csMMEP syndromMCOPS8 · Syndromická mikroftalmie, typ 8 · Syndrom zahrnující mikrocefalii, mikroftalmii, ektrodaktylii dolních končetin a prognatii · Viljoenův-Smartův syndrom · Viljoen-Smartův syndrom
ukСиндром ММЕРMCOPS8 · Синдром мікроцефалії-мікрофтальмії-екстродактилії нижніх кінцівок- прогнатизму · Синдромна мікрофтальмія типу 8 · Синдром Вілджоена-Смарта
zhMMEP综合征小头-小眼-先天性下肢缺指-凸颌综合征
trMMEP sendromuMCOPS8 · Viljoen-Smart sendromu · Sendromik mikroftalmi tip 8 · Alt ekstremite mikrosefali-mikroftalmi-ektrodaktili-öne çıkık çene sendromu

Definition in:

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Cross-references

qualifier = Orphanet mapping relation
SourceCodeQualifierICD relationValidation
OMIM601349Evalidated
ICD-10Q87.8NTBTattributedvalidated
ICD-11LD21.0NTBTindexvalidated
MONDO0011045Evalidated
MeSHC537686Evalidated
UMLSC1832440Evalidated
GARD3693Evalidated

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 (3):

No children.

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Genes

0 direct

Orphanet records no gene directly on this code.

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Prevalence and incidence

1 record
TypeClassValueAreaQualificationValidationSource
Point prevalenceUnknown—WorldwideClass onlyNot yet validatedORPHANET

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

11 annotations · validated 2016-06-01
HPOTerm (as annotated by Orphanet)Diagnostic
Very frequent (99-80%)
HP:0001249Intellectual disability
HP:0000303Mandibular prognathia
HP:0000161Median cleft lip
HP:0000252Microcephaly
HP:0000568Microphthalmia
HP:0000202Orofacial cleft
HP:0001839Split foot
Frequent (79-30%)
HP:0000028Cryptorchidism
HP:0001199Triphalangeal thumb
HP:0000505Visual impairment
Occasional (29-5%)
HP:0001629Ventricular septal defect

Run the differential on the 7 obligate / very frequent terms

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Sources for this card