1. State Key Laboratory of Genetic Engineering and National Center for International Research of Development and Disease, Collaborative Innovation Center for Genetics and Development, Fudan-Yale Biomedical Research Center, Institute of Developmental Biology and Molecular Medicine, Fudan University, Shanghai 200433, China.
2. Howard Hughes Medical Institute, Department of Molecular, Cellular, Developmental Biology, University of Colorado at Boulder, Boulder, CO 80309, USA.
3. Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA.
4. Howard Hughes Medical Institute, Department of Genetics, Yale University School of Medicine, New Haven, CT 06536, USA.
* These authors contribute equally to this work.
Balancer chromosomes are important tools for a variety of genetic manipulations in lower model organisms, owing to their ability to suppress recombination. In mouse, however, such effort has not been accomplished, mostly due to the size of the chromosomes and the complexity of multiple step chromosomal engineering. We developed an effective and versatile cassette-shuttling selection (CASS) strategy involving only two selection markers to achieve the sequential production of multiple large inversions along the chromosome. Using this strategy, we successfully generated the first full-length balancer in mice and showed that Balancer 17M-GFP can efficiently suppress recombination. Our study has not only generated a useful genetic resource, but also provided a strategy for constructing mammalian balancer chromosomes.
Keywords: Mouse full-length balancer chromosome, cassette-shuttling selection (CASS) strategy, 17M-GFP.