RNF17 is a ring finger E3 ubiquitin ligase with critical roles in DNA damage responses and male fertility. In the DNA damage response pathway, RNF17 functions as an E3 ligase that partners with the E2 enzyme UBE2U to regulate RNF168, a key player in 53BP1 mobilization to ionizing radiation-induced DNA double strand breaks 1. This E3-E2 pair is essential for enforcing proper cellular responses to genotoxic stress. RNF17 also plays a central role in germ cell development and spermatogenesis. It is expressed as a molecular marker in primordial germ cells and spermatogonial stem cells 23, and appears among the most predictive candidate markers for male fertility impairment in a comprehensive fertility relevance probability analysis 4. Notably, RNF17 exhibits recent population-specific positive directional selection in human testis-enriched genes, suggesting adaptation to environmental conditions affecting spermatogenesis 5. Furthermore, rare non-silent variants in RNF17 accumulate significantly in non-obstructive azoospermia patients, indicating genetic associations with male infertility 6. RNF17 is also identified as a hub gene and cancer antigen in urothelial cancer gene regulatory networks 7, though its precise mechanism in tumorigenesis remains unclear.