Therefore, the identification of the sequence or function of a gene in a model organism, for example, the roundworm C elegans, has the potential to explain a homologous gene in human beings, or in one of the other model organisms. These ambitious goals required and will come to demand a variety of new technologies that have made it possible to relatively rapidly construct a first draft of the human genome and to continue to refine that. These technologies include: DNA sequencing, RFLP, Yeast artificial chromosomes, bacterial artificial chromosomes, PCR, and electrophoresis.