[
2003]
Since the publication of the first genetic research paper on Caenorhabditis elegans (C. elegans for short) in 1974, this microscopic, free-living nematode has become a popular model organism to study development, neurobiology, and other biological problems. The ability to do powerful genetics has been the most critical reason why studies using this organism have made enormous contributions to basic biology and medical science. Therefore, C. elegans genetics should be part of any modern genetic education. In this chapter, we describe some of the unique properties of C. elegans that makes it an exceptional organism for genetic and molecular biological research. Some important genetic tools and methodologies developed by C. elegans researchers will also be introduced. We aim to connect the fundamental principles of genetics as described in early chapters with practical applications of these principles in actual research. We have chosen a few genetic pathways and biological problems as examples for illustrating the logic behind the genetic analyses and for introducing some commonly practiced strategies and methods. We do not hesitate to introduce some of the most advanced and up-to-date methods and approaches, including those developed since the genome sequence was determined in 1998. We believe today's students can go right into the heart of present research after learning the basic principle of Genetics (see the early chapters of this book) and molecular biology. In fact, in many C. elegans laboratories, undergraduate students are doing a wide variety of experiments using the genetic techniques