A process for constructing a chimeric non-human animal characterized by preparing microcells containing one or more foreign chromosomes or fragments thereof, and transferring the one or more foreign chromosomes or fragments thereof into pluripotent cells through fusion with the microcells; chimeric non-human animals which can be constructed by the above process and offspring thereof; tissues and cells originating in the above animals; methods for using the individuals, tissues and cells of the animals; pluripotent cells containing one or more foreign chromosomes or fragments thereof, a process for constructing these cells, and the use of these cells; pluripotent cells in which at least two intrinsic genes have been disrupted; a process for constructing the above cells by homologous recombination; etc.

Pluripotent cells having disrupted intrinsic genes

PURPOSE:To provide an embryo-undifferentiated (ES) cell originated from a mouse of a strain other than 129 mouse and capable of efficiently producing descendant mice. CONSTITUTION:The objective embryo-undifferentiated (ES) cell originated from a 4-days embryo obtained by crossing a female of C57BL/6 mouse with a male of CBA mouse and characterized by the generation of chimera mouse from a 3-days embryo (8-cell embryo) and free from generation of chimera mouse from a 4-days embryo. The ES cell is e.g. TT2 embryo undifferentiated (ES) cell of FERM P-12971.

Tokunaga Tomoyuki

Papers

Embryo-undifferentiated cell