International Mammalian Genome Society

The 15th International Mouse Genome Conference (2001)

Table of Contents * Complex Genetics * Developmental Genetics * Gene Annotation * Gene Discovery * Genome Sequencing * Functional Genomics * Mutagenesis * Presentations * Verne Chapman Memorial Lecture

Dr. Maki Inoue
RIKEN Genomic Sciences Center
214 Maeda-cho, Totsuka-ku
Yokohama
244-0804
Japan

Co-Authors: 1)Inoue M, 1)Suzuki T, 1)Masuya H, 1)Toki H, 2)Shibuya T, 1)Minowa O, 1)Wakana S, 3)Gondo Y, 1)Noda T, 1)ShiroishI T
Institutions: Mouse Functional Genomics Research Group, RIKEN Genomic Sciences Center. 2) Hatano Research Institute, Food and Drug Safety Center, 3)Population and Quantitative Genomics Team, RIKEN Genomic Sciences Center

We initiated ENU-mutagenesis with C57BL/6J (B6), and have obtained a number of phenodeviants to date. To expand a spectrum of mutant phenotypes to be screened, we have a plan to use MSM strain, which was derived from a Japanese wild mouse, as a target strain in ENU mutagenesis program of RIKEN GSC. In this study, we examined susceptibility of the MSM strain to ENU, in comparison to that of B6 strain. We administered several different dosages of ENU to MSM male mice. In a dosage of 3 X 75 mg/kg at weekly interval, almost all B6 males produced litters by week 15 after the final injection, and their average sterility period was 11 weeks. About 50% of the mice died by week 16-18 mainly due to thymic lymphoma. By contrast, all of MSM males in the same dosage group were sterile but survived until week 20. These data show that ENU-susceptibility of the MSM strain is different from that of B6 strain for the carcinogenicity and cytotoxicity. We discuss here effective ENU dosages for the two strains, and, we present our current results of screenings for the G1 animals generated from the mutagenized B6 males.