Craniofacial malformations: intrinsic vs extrinsic neural crest cell defects in Treacher Collins and 22q11 deletion syndromes

Clin Genet. 2006 Jun;69(6):471-9. doi: 10.1111/j.0009-9163.2006.00615.x.


The craniofacial complex is anatomically the most sophisticated part of the body. It houses all the major sensory organ systems and its origins are synonymous with vertebrate evolution. Of fundamental importance to craniofacial development is a specialized population of stem and progenitor cells, known as the neural crest, which generate the majority of the bone, cartilage, connective and peripheral nerve tissue in the head. Approximately one third of all congenital abnormalities exhibit craniofacial malformations and consequently, most craniofacial anomalies are considered to arise through primary defects in neural crest cell development. Recent advances however, have challenged this classical dogma, underscoring the influence of tissues with which the neural crest cells interact as the primary origin of patterning defects in craniofacial morphogenesis. In this review we discuss these neural crest cell interactions with mesoderm, endoderm and ectoderm in the head in the context of a better understanding of craniofacial malformations such as in Treacher Collins and 22q11 deletion syndromes.

Publication types

  • Comparative Study
  • Review

MeSH terms

  • Chromosome Deletion*
  • Chromosomes, Human, Pair 22 / genetics*
  • DiGeorge Syndrome / embryology*
  • DiGeorge Syndrome / genetics*
  • DiGeorge Syndrome / physiopathology
  • Humans
  • Mandibulofacial Dysostosis / embryology*
  • Mandibulofacial Dysostosis / genetics*
  • Mandibulofacial Dysostosis / physiopathology
  • Neural Crest / abnormalities*
  • Neural Crest / pathology