The completion of the human genome map has contributed to the identification of the functions of some of the human genes; nonetheless, those of many other genes are still unknown. The ultimate purpose of future biotechnology is to identify unknown gene functions.

With their advantages of easy experimental access and great similarities to the human genome, transgenic mice are used in research on gene functions in vitro and disease models; thus greatly contributing to the development of the medical science field. Likewise, they are expected to serve as important tools for functional genomic research, which will be pivotal to future biotechnology.