Abstract:Objective Investigate the application of in vitro fertilization (IVF) and embryo cryopreservation in C57-ras transgenic mice. Methods 2-cell embryos were collected in two ways, first of which is by 4-week superovulated C57BL/6J female mice mated with C57-ras transgentic male mice, and the other is by IVF. The 2-cell embryos were cryopreserved after that. Then the cryopreserved 2-cell embryos were thawed and transplanted to caculate the ratio. Genetype of offsprings were analysed by PCR. Results The average recovery rate of cryopreserved normal 2-cell embryo was 67.78%?.08, and 21.31%?.09 were born after thawed 2-cell embryos transplanted. 23.08%?.14 of the offsprings were positive of human c-Ha-ras gene; The average recovery rate of cryopreserved IVF 2-cell was 63.33%?.03, and 15.56%?.04 were born after transplanted, and 33.33% of the offspring were positive . Conclusion The results suggested that there was no significant difference in cryopreservation of normal and IVF C57-ras 2-cell embryos. The research provided the cryopreservation method for C57-ras transgenic mouse model.