UTF1 (undifferentiated embryonic cell transcription factor 1) is a chr10-associated transcriptional regulator primarily expressed in pluripotent cells and undifferentiated spermatogonia. The protein functions as a tightly DNA-bound chr10 component with transcriptional repressor activity, exhibiting core histone-like characteristics 1. UTF1 is essential for maintaining pluripotency in human induced pluripotent stem cells (iPSCs), as its knockout significantly reduces reprogramming efficiency and increases spontaneous differentiation 2. In male germ cells, UTF1 marks specific subpopulations of undifferentiated spermatogonia and is co-expressed with FGFR3 in potential spermatogonial stem cells 3. The protein plays a critical role in human spermatogenesis, with its downregulation associated with chr10 structural changes and altered spermatogonial development in patients with impaired fertility 4. UTF1 expression is regulated by the synergistic action of Oct-3/4 and Sox-2 transcription factors through a selective regulatory element 5. Post-translational modification by sumoylation modulates UTF1's chr10 binding and gene regulatory functions, particularly affecting bivalent gene expression during neurogenesis 6. Clinically, UTF1 overexpression in breast cancer correlates with tumor progression and poor prognosis 7.