212 - Neuroembryology and Molecular Genetics of the Brain

Abstract

Central nervous system development is a dynamic morphogenetic process that is among the earliest of the organ systems established postconception in the embryo. From the creation of the neural plate, which will ultimately give rise to the neural tube, there are multiple layers of cell proliferation, migration, shape changes, and cell signaling/crosstalk that must occur in a temporally and spatially defined manner. Failure to do so properly results in a collection of congenital malformations known as neural tube defects, which are the second most common structural birth defect in humans. This chapter focuses on the development and maturation of the neural tube into the brain and spinal cord, and, wherever possible, attempts to summarize the rapidly evolving molecular genetic landscape that orchestrates these events. The field is constantly evolving such that much of the molecular genetic descriptions in the text might be outdated by the time it is in print. However, the reader is encouraged to follow the authors of many of the recent publications cited within, as these same groups are likely to be continuing to inform our understanding of the genetic aspects of normal and abnormal development of the central nervous system. Abnormal central nervous system development includes various subtypes from mild to severe. Depending on where and when the impairment occurs, the clinical outcomes will vary. In this chapter, the different types of neural tube defects are be presented, with an overview of the embryonic origin, the relevance of cell survival equilibrium, and the clinical features with a summary of known epidemiology and possible management.