A disease model pig produced by nuclear transplantation, a disease model pig exhibiting a stable phenotype, and a production method of these are provided. A chimera pig for producing a disease model pig exhibiting a stable phenotype, the reproductive gland thereof and germ cells thereof are also provided.This method for producing a genetically modified disease model pig involves (a) using the nucleus of genetically modified cells for nuclear transplantation into ooplasm, (b) obtaining offspring by producing the obtained cloned embryo in the uterus of a female pig, (c) cross-breeding, or allowing sexual reproduction, of the obtained offspring to obtain further genetically modified offspring as disease model pigs. Or, the method for producing a lethal genetic disease model pig involves (i) using the nucleus of genetically modified cells for nuclear transplantation into ooplasm, (ii) obtaining offspring by producing, in the uterus of a female pig, the cloned embryo obtained by nuclear transplantation and brought into a chimeric state with the embryo of a pig that does not exhibit the genetic disease, (iii) cross-breeding the obtained offspring, or providing the germ cells of the obtained offspring for sexual reproduction to obtain female offspring that has said genetic modification, and (iv) cross-breeding the obtained female offspring with a male pig, or allowing sexual reproduction, to obtain a lethal genetic disease model pig.Linvention concerne un porc servant de modèle de maladie, produit par transplantation nucléaire, un porc servant de modèle de maladie présentant un phénotype stable et un procédé de production de ceux-ci. Un porc chimère pour produire un porc servant de modèle de maladie présentant un phénotype stable, la glande de reproduction correspondante et des cellules germinales correspondantes sont également décrits. Ce procédé de production dun porc génétiquement modifié servant de modèle de maladie consiste à (a) utiliser le noyau de cellules génétiqu
