We disclose that a target organ such as kidney can be regenerated by complementing a developmental deficiency leading to a lack of development of the target organ in a non- human first mammal by injecting a somatic cell nuclear transfer cell (SCNT cell) into a developed blastocyst of the non-human first mammal. We also disclose a method for producing a target organ, using an SCNT cell, in a living body of a non-human first mammal having an abnormality associated with a lack of development of the target organ in a development stage, the target organ produced being derived from a second mammal that is an individual different from the non-human first mammal.
