title: Molecular control of facial morphology.
abstract: We present a developmental perspective on the concept of phylotypic and phenotypic stages of craniofacial development. Within orders of avians and mammals, a phylotypic period exists when the morphology of the facial prominences is minimally divergent. We postulate that species-specific facial variations arise as a result of subtle shifts in the timing and the duration of molecular pathway activity (e.g., heterochrony), and present evidence demonstrating a critical role for Wnt and FGF signaling in this process. The same molecular pathways that shape the vertebrate face are also implicated in craniofacial deformities, indicating that comparisons between and among animal species may represent a novel method for the identification of human craniofacial disease genes.
authors.affiliation: Division of Plastic and Reconstructive Surgery, Department of Surgery, Stanford School of Medicine, Stanford University, Stanford, CA 94305, United States.
authors.forename: B
authors.initials: B
authors.lastname: Liu
authors.forename: S M
authors.initials: SM
authors.lastname: Rooker
authors.forename: J A
authors.initials: JA
authors.lastname: Helms
mesh_terms: D000818:Animals; D051778:Basic Helix-Loop-Helix Leucine Zipper Transcription Factors / Q000378:metabolism; D019521:Body Patterning; D015509:Developmental Biology / Q000379:methods*; D005145:Face / Q000196:embryology* / Q000502:physiology; D005346:Fibroblast Growth Factors / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D051821:Lymphoid Enhancer-Binding Factor 1 / Q000378:metabolism; D008954:Models, Biological; D009432:Neural Crest / Q000502:physiology*; D010641:Phenotype; D015398:Signal Transduction; D000073940:Transcription Factor 4; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D051778:Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; C497573:LEF1 protein, human; D051821:Lymphoid Enhancer-Binding Factor 1; C532096:TCF4 protein, human; D000073940:Transcription Factor 4; D014157:Transcription Factors; D005346:Fibroblast Growth Factors