The RCAS retroviral expression system in the study of skeletal development

RCAS is a replication-competent retroviral vector system that allows sustained misexpression of a gene of interest in avian cells. This tool has been used to gain fundamental insights into skeletal development in the chick embryo, and consequently into broader principles of morphogenesis. In this review, we discuss a range of RCAS-based strategies that have been employed to examine gene function during early patterning of the limb bud, later skeletal differentiation, and craniofacial morphogenesis. The potential for the RCAS system as a tool for loss-of-function studies is also discussed.