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Unusual variant of holoprosencephaly in monosomy 13q

Pascale Marcorelles1, Philippe Loget, Catherine Fallet-Bianco

  • 1Service d'Anatomie Pathologique, CHU, Hôpital Morvan, 29609 Brest Cedex, France.

Pediatric and Developmental Pathology : the Official Journal of the Society for Pediatric Pathology and the Paediatric Pathology Society
|March 23, 2002
PubMed

Insights

Terminal deletion of chromosome 13q causes brain malformations, including a specific clover-shaped holoprosencephaly. This condition may be linked to the ZIC2 gene on chromosome 13q.

Area of Science:

  • Genetics
  • Developmental Biology
  • Neurology

Background:

  • 13q- syndrome involves significant congenital malformations, particularly affecting the brain.
  • Holoprosencephaly is a spectrum of brain malformations characterized by incomplete separation of the forebrain.

Observation:

  • Five cases of a unique clover-shaped holoprosencephaly (syntelencephaly) were identified in fetuses with 13q- syndrome.
  • This specific cerebral midline anomaly, termed syntelencephaly, has been rarely described, primarily through advanced imaging techniques.

Findings:

  • The observed syntelencephaly in 13q- fetuses aligns with previously reported cases.
  • The ZIC2 gene, associated with holoprosencephaly, is located on chromosome 13q32, the same region affected in 13q- syndrome.

Implications:

  • The findings suggest a potential causal link between ZIC2 gene loss of function and the observed syntelencephaly in 13q- syndrome.
  • This research highlights the critical role of the ZIC2 gene in forebrain development and provides insight into the etiology of specific holoprosencephaly types.

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