Lineage analysis with retroviral vectors

Publisher Summary Knowledge of the genealogical relationships of cells during development provides an insight concerning when and where developmental decisions are being made. Hypotheses can be ruled in or out concerning the commitment of cells to particular fates. For example, when analyzing the cell types that result from the marking of a single progenitor cell, insight can be gained as to whether the progenitor is committed to the production of one or multiple cell types. If multiple cell types are found in a clone, it may be concluded that the progenitor that gave rise to these cells is not restricted to the production of only one cell type. If all of the cells that descend from a progenitor are the same type, the hypothesis is supported that the progenitor is committed to making only that cell type. The complexity and inaccessibility of many types of embryos have made lineage analysis through direct approaches, such as time-lapse microscopy and injection of tracers, almost impossible. A genetic and clonal solution to lineage mapping is the use of retrovirus vectors. The chapter summarizes the basis of this technique, and discusses the current methods and strategies used in the laboratory.