GENETICALLY-ENGINEERED MICE - TOOLS TO UNDERSTAND CRANIOFACIAL DEVELOPMENT

In this review, we provide a survey of the experimental approaches use d to generate genetically engineered mice. Two specific examples are p resented that demonstrate the applicability of these approaches to cra niofacial development. In the first, a promoter analysis of the Msx2 g ene is presented which illustrates the cis regulatory interactions tha t define cell-specific gene expression. In the second, a mouse model o f the human disease craniosynostosis, Boston type, has been created by misregulation of the Msx2 gene product. Finally, we present a formula ry of spontaneously occurring and genetically engineered mice that exh ibit defects in developmental professes affecting the craniofacial com plex. The purpose of this review is to provide insight into the experi mental approaches that are used to create genetically engineered mice and to impress upon the reader that genetically engineered mice are we ll-suited to address fundamental questions pertaining to the developme nt, maintenance, and regeneration of tissues and organs.