This book provides the background to the construction, characterization, and use of somatic cell hybrids. Particular attention is paid to their application in human gene mapping and in studies of gene expression, although other uses are also covered. The increasing utilization of somatic cell hybrids in biological research suggests there is a real need for a full description of how to make and use these cell lines and no other book covers this field as comprehensively. A number of techniques are clearly explained. This volume offers a useful introduction to the field for undergraduates, researchers at the beginning of their careers, and established scientists who wish to employ these techniques for the first time.