Disruption of the Hedgehog signaling pathway has been implicated as an important molecular mechanism in the pathogenesis of fetal alcohol syndrome. In severe cases, the abnormalities of the face and brain that result from prenatal ethanol exposure fall within the spectrum of holoprosencephaly. Single allele mutations in the Hh pathway genes Sonic Hedgehog (SHH) and GLI2 cause holoprosencephaly ...

Congenital nasal pyriform aperture stenosis (CNPAS) is a rare condition related to holoprosencephaly in which bony overgrowth of the medial process maxilla narrows aperture. CNPAS presents neonates with signs upper airway obstruction ranging from mild severe respiratory distress and failure thrive. Surgical intervention indicated after failed conservative measures generally includes temporary s...

PURPOSE OF REVIEW Holoprosencephaly (HPE) is the most common anomaly of forebrain development in humans. The pathogenesis of HPE results in a failure of the brain hemispheres to separate during early development. Here we review experimental models of HPE in which some of the genes known to cause HPE in humans have been disrupted in the mouse. RECENT FINDINGS To date, mutations that cause HPE ...

Holoprosencephaly (HPE) is a brain malformation which results from a primary defect in induction and patterning of the rostral neural tube during early embryogenesis and usually considered as an impaired cleavage of the prosencephalon. The review of neuropathologic findings highlights a complex malformation involving not only the prosencephalon but also the whole brain, the eyes, and the cerebr...

Holoprosencephaly (HPE) is a malformation that arises during the first 4 weeks of embryonic development (blastogenesis)[1] caused by a failure or incomplete division of the prosencephalon into cerebral hemispheres. This defect is frequently associated with other facial anomalies such as anophthalmia, cyclopia, proboscis, midface clefting, hypertelorism, single maxillary central incisor, and abs...

The roof plate is a well known signaling center in CNS development, but its roles in the developing telencephalon and the common holoprosencephaly (HPE) malformation have been uncertain. Using cellular ablations in mice, we show that roof plate cell loss causes failed midline induction and HPE in the dorsal telencephalon. This morphologic phenotype is accompanied by selective deficits in midlin...