Abstract: | The fused gag-v-myc oncogene was microinjected into fertilized mouse eggs, which were then implanted into foster mothers. Approximately 26% of the offsprings from injected eggs carried v-myc sequences. 26 of 32 progeny animals were found to be transgenic and some progeny containing the amplified oncogene (about 40 copies per genome). In one F0 and one F1 mice 1.5-2 months after birth the development of tumors was observed: rhabdomyosarcoma and sebaceous carcinoma. In both the cases the tumors were highly differentiated. Because spontaneous tumors of these types are seldom observed in common lines of mice it seems probable that the tumors observed in this study may be associated with the presence of oncogene v-myc. |