Page "Holoprosencephaly" Paragraph 11

Holoprosencephaly consists of a spectrum of defects or malformations of the brain and face.

At the most severe end of this spectrum are cases involving serious malformations of the brain, malformations so severe that they often cause miscarriage or stillbirth.

At the other end of the spectrum are individuals with facial defects which may affect the eyes, nose, and upper lip-and normal or near-normal brain development.

Seizures and mental retardation may occur.