ATG12 protein is a crucial factor in the process of autophagy, serving as a human homolog of yeast autophagy-related genes. It plays an essential role in the formation of autophagosomes, the double-membrane structures that engulf and degrade cellular components. ATG12 forms a complex with ATG5 by being conjugated to it through the action of E1-like enzyme ATG7 and E2-like enzyme ATG10, and then this complex non-covalently binds with ATG16 to form the ATG12-ATG5-ATG16 complex, which is vital for the expansion of the autophagosome membrane. In terms of pathology, the expression of the ATG12 protein is associated with various diseases. For instance, reduced expression of ATG12 in cervical cancer tissue may be involved in the development of cervical cancer. Furthermore, the expression level of ATG12 correlates with the risk of recurrence after cervical conization surgery, with lower expression potentially increasing the risk of persistent or recurrent lesions.