For example, generation and breeding of another mouse line harboring Disc1 L100P, which can be accomplished by in vitro fertilization by the cryopreserved sperm of the G1 progeny owned by RIKEN BRC, may facilitate full elucidation of a relationship between genetic components, including Disc1 L100P mutation per se, and behavioral phenotypes, related with schizophrenia in this mouse line. The gene discussed is DISC1; the disease is schizophrenia.