It is intended to develop and provide a more convenient method of stably inhibiting the expression of a target gene throughout embryogenesis. Further, it is intended to develop and provide a method of constructing an animal with inhibited gene expression by a more convenient procedure. A more convenient method of stably inhibiting the expression of a target gene throughout embryogenesis can be provided by injecting a double-stranded RNA (dsRNA) corresponding to the full sequence of the target gene or a part thereof into the nucleus of a fertilized or unfertilized egg. An animal with inhibited gene expression can be constructed by preparing a fertilized egg, which contains a dsRNA corresponding to the full sequence of the target gene or a part thereof in its nucleus and in which the expression of the target gene is stably inhibited, and growing the fertilized egg in a female body.
