PROBLEM TO BE SOLVED: To provide a liver disease preventive or therapeutic medicine for finding a gene for protectively acting on a liver disease due to a chemical material, such as a drug, and incorporated with a gene function, its screening system, and a system for evaluating the liver disease which uses the gene.SOLUTION: The present invention includes a screening method of the liver disease preventive or therapeutic medicine for considering a Mmd2 expression level as an index. The liver disease preventive or therapeutic medicine includes an expression vector of a Mmd2 polypeptide. A method for manufacturing a nonhuman animal model of the liver disease includes the induction of liver disease in a nonhuman mammal, by administering the chemical material for inducing the liver disease to the nonhuman mammal, in which a Mmd2 polypeptide expression level is reduced in the liver.
