Zinc fingerprint structure transcription factor, responsible for regulating the self -update of embryo stem cells, is a key gene in many tumors. It plays an important role in embryo development. It is stem cell marker and tumor embryo protein, similar to AFP. SALL4 is the sensitivity and specific marker of seminoma and ovarian germ cell tumor. In pathology, the diagnosis of germ cell tumors is mainly used. It is also used in the identification of gastric liver cancer and Hepatocellular carcinoma, and diagnosis of yolk sac tumor and clear cell carcinoma of the ovary.