Abstract: The present invention provides genetically modified non-human animals which are deficient in at least one or more types of CD3 genes selected from the group consisting of endogenous CD3?, CD3?, and CD3? in its genome and functionally express at least one or more types of human CD3 genes selected from the group consisting of human CD3?, CD3?, and CD3?. In the genetically modified non-human animals of the present invention, mature T cell differentiation and production can take place, and immunocompetent cells including T cells can exert their functions. The genetically modified non-human animals of the present invention enable efficient evaluation and screening in the development of therapeutic agents and therapeutic methods that use human CD3-mediated targeted drugs.

Abstract: An object of the present invention is to provide an evaluation system capable of detecting an extracellular purinergic receptor ligand minimally invasively, chronologically and systemically, and the present invention provides a genetically modified non-human animal expressing a first fusion protein and a second fusion protein for detecting an extracellular purinergic receptor ligand, in which the first fusion protein comprises a membrane protein that binds to a purinergic receptor ligand, and a first reporter protein, and the second fusion protein comprises a protein that binds to the membrane protein bound to the ligand, and a second reporter protein; and a cell thereof.

Abstract: The present invention provides a non-human animal in which a DNA comprising an hp7 sequence-encoding DNA and a poly A addition signal-encoding DNA added on the 3? side of a DNA encoding an arbitrary foreign gene is inserted in the same reading frame as that of an arbitrary target gene present on the genome of the non-human animal.

Abstract: The present invention provides genetically modified non-human animals which are deficient in at least one or more types of CD3 genes selected from the group consisting of endogenous CD3?, CD3?, and CD3? in its genome and functionally express at least one or more types of human CD3 genes selected from the group consisting of human CD3?, CD3?, and CD3?. In the genetically modified non-human animals of the present invention, mature T cell differentiation and production can take place, and immunocompetent cells including T cells can exert their functions. The genetically modified non-human animals of the present invention enable efficient evaluation and screening in the development of therapeutic agents and therapeutic methods that use human CD3-mediated targeted drugs.

Abstract: The present invention provides a non-human animal in which a DNA comprising an hp7 sequence-encoding DNA and a poly A addition signal-encoding DNA added on the 3? side of a DNA encoding an arbitrary foreign gene is inserted in the same reading frame as that of an arbitrary target gene present on the genome of the non-human animal.

Abstract: The present invention provides a transgenic animal expressing the full-length human hepatitis C virus (HCV) for the purpose of constructing a system for screening for a remedy for human hepatitis C. The present invention is a transgenic hepatitis C model animal, which has the full-length DNA of the hepatitis C virus incorporated therein and can express the full-length HCV gene, and a method of generating a hepatitis C model animal carrying the full-length HCV gene, which comprises introducing a vector containing the full-length DNA of hepatitis C virus into an ES cell, and causing the ES cells to undergo ontogenesis in a pseudo-parent.