Role of neural crest in congenital heart disease.

In the preface for his monograph on neural crest in 1950, Horstadius' wrote, "Most text-books of embryology or anatomy make only passing mention of the neural crest as the source of origin of one or two structures in the vertebrate body. Few books devote even as much as a page to this interesting structure." Although the passage of 40 years has seen a revolution in our understanding of the neural crest in basic and clinical sciences, Horstadius' statement is still applicable to the paucity of information about neural crest in textbooks. Unfortunately, among scientists and clinicians not directly involved in neural crest research, this has led to almost profound ignorance about the neural crest and its role in development. The neural crest is an unusual structure that appears early in development and has only a transient existence because the cells of the neural crest quickly migrate throughout the body and differentiate into other cell types. Its transience and widespread migration have made neural crest derivatives a technical challenge to study. Because of these difficulties, knowledge of neural crest derivatives progressed somewhat haltingly through the last half of the 19th century and the first half of the 20th century, dependent on development of novel techniques with which to study this labile population of cells. In the past 40 years, with the availability of tissue culture, autoradiography, interspecies transplantation, immunohistochemistry, and in situ hybridization, we have begun to understand much more about neural crest derivatives.2 The neural crest has been recognized primarily for its contribution to the peripheral nervous system, although the largest portion of Horstadius' 1950 monograph1 is devoted to non-neural derivatives of the neural crest in the-vertebrate head and branchial region. In 1888, Kastschenko first claimed that some mesenchyme of the head originated from the neural crest.' Platt (1893-1897) showed that cartilage of the visceral arches and dentine of the teeth were derived