a high-speed congenic strategy using first-wave male germ cells高速句策略使用抗雄性生殖细胞.pdfVIP

A High-Speed Congenic Strategy Using First-Wave Male Germ Cells 1 1,2 1 1 1 3,5 Narumi Ogonuki , Kimiko Inoue , Michiko Hirose , Ikuo Miura , Keiji Mochida , Takahiro Sato , 1 1 1 1 3 1 Nathan Mise , Kazuyuki Mekada , Atsushi Yoshiki , Kuniya Abe , Hiroki Kurihara , Shigeharu Wakana , Atsuo Ogura1,2,4* 1 RIKEN BioResource Center, Tsukuba, Ibaraki, Japan, 2 Graduate School of Life and Environmental Science, University of Tsukuba, Tsukuba, Ibaraki, Japan, 3 Department of Physiological Chemistry and Metabolism, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan, 4 Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan, 5 Tsukuba Safety Assessment Laboratories, Banyu Pharmaceutical Company Limited, Tsukuba, Ibaraki, Japan Abstract Background: In laboratory mice and rats, congenic breeding is essential for analyzing the genes of interest on specific genetic backgrounds and for analyzing quantitative trait loci. However, in theory it takes about 3–4 years to achieve a strain carrying about 99% of the recipient genome at the tenth backcrossing (N10). Even with marker-assisted selection, the so- called ‘speed congenic strategy’, it takes more than a year at N4 or N5. Methodology/Principal Findings: Here we describe a new high-speed congenic system using round spermatids retrieved from immature males (22–25 days of age). We applied the technique to three genetically modified strains of mice: transgenic