title: Perspectives on holoprosencephaly: Part III. Spectra, distinctions, continuities, and discontinuities.
abstract: This paper attempts to balance our knowledge of holoprosencephalic spectra and continuities with important distinctions and discontinuities. Prevalence studies and syndrome delineation are briefly reviewed. The following topics receive detailed coverage: human teratogens, special aspects of forebrain and hindbrain malformations, aprosencephaly/atelencephaly, association with neural tube defects, current assessment of "facial principles," and endocrine abnormalities.
authors.affiliation: Department of Oral Biology, Faculties of Dentistry and Medicine, Dalhousie University, Halifax, NS, Canada.
authors.forename: M M
authors.initials: MM
authors.lastname: Cohen
mesh_terms: D000015:Abnormalities, Multiple / Q000453:epidemiology*; D001921:Brain / Q000002:abnormalities*; D005147:Facial Bones / Q000002:abnormalities; D006801:Humans; D015995:Prevalence; D013577:Syndrome; D013723:Teratogens
chemical_list: D013723:Teratogens