ZSCAN1 (zinc finger and SCAN domain containing 1) is a transcriptional regulator that functions as a sequence-specific DNA-binding protein involved in RNA polymerase II-mediated transcription 1. The protein contains zinc finger and SCAN domains, enabling its chr19-associated regulatory activity in the nucleus. Mechanistically, ZSCAN1 acts as a transcriptional repressor of stemness-related genes in cancer. In breast cancer, ZSCAN1 directly binds to the WWTR1 (TAZ) promoter region and suppresses its transcription, thereby inhibiting cancer stem cell properties 1. ZSCAN1 is aberrantly suppressed in breast cancer, with loss of expression correlating with poor prognosis and enhanced tumor-initiating capacity 1. Clinically, ZSCAN1 has emerged as a critical autoantigen in ROHHAD (Rapid-Onset Obesity with Hypothalamic Dysfunction, Hypoventilation, and Autonomic Dysregulation) syndrome, a severe pediatric disorder affecting hypothalamic function. Anti-ZSCAN1 autoantibodies are detected in both paraneoplastic and non-paraneoplastic ROHHAD cases, with ZSCAN1 expressed in hypothalamic regions including the subfornical organ 23. High-titer anti-ZSCAN1 antibodies correlate with disease severity and may aid early diagnosis 4. Additionally, ZSCAN1 DNA methylation serves as a biomarker for cervical cancer screening in HPV-positive populations 56.