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Midline interhemispheric variant of holoprosencephaly

Disease definition

Midline interhemispheric variant of holoprosencephaly (MIH) or syntelencephaly is a form of holoprosencephaly (HPE; see this term) characterized by non-separation of the posterior frontal and parietal lobes, normally-formed callosal genu and splenium, absence of the callosal body, normally-separated hypothalamus and lentiform nucleus, and frequent heterotopic gray matter.


Classification level: Subtype of disorder
  • Synonym(s):
    • MIH
    • MIH type HPE
    • MIHF
    • MIHV
    • Middle interhemispheric fusion variant
    • Middle interhemispheric variant of holoprosencephaly
    • Syntelencephaly
  • Prevalence: Unknown
  • Inheritance: Multigenic/multifactorial or Not applicable 
  • Age of onset: Infancy, Neonatal
  • ICD-10: Q04.2
  • ICD-11: LA05.2
  • OMIM: 157170  609637  610829
  • UMLS: -
  • MeSH: -
  • GARD: -
  • MedDRA: -

Detailed information

Disease review articles

Genetic Testing

ERN : produced/endorsed by ERN(s)
FSMR : produced/endorsed by FSMR(s)
The documents contained in this web site are presented for information purposes only. The material is in no way intended to replace professional medical care by a qualified specialist and should not be used as a basis for diagnosis or treatment.