Gonocyte transformation in a congenitally cryptorchid rat is normal and may be similar to the situation reported in human acquired cryptorchidism

Study in congenitally cryptorchid TS rats demonstrates normal gonocyte transformation occurs before testicular descent failure, explaining why these animals develop infertility but not cancer. This timing difference suggests the TS rat model may better represent acquired human cryptorchidism where testicular maldescent occurs after completion of early germ cell development.