Holoprosencephaly sequence.

Holoprosencephaly (HPE) sequence is a rare spectrum of cerebral and facial malformations resulting from incomplete division of the embryonic forebrain into distinct lateral cerebral hemisphere. Three ranges of increasing severity are described: lobar, semi-lobar and alobar HPE. A subtype of HPE called middle inter-hemispheric variant (MIHF) has been also reported. The etiology is heterogeneous: teratogens, chromosomal abnormalities and single gene mutations can be involved. Holoprosencephaly results in early morbidity and mortality with a reduced survival beyond neonatal period. The disorder is estimated to occur in 1/16,000 live births. This case report presents a male new born diagnosed with holoprosencephaly, accompanied by median cleft palate, absent nasal bones and chromosomal abnormalities.