RING finger protein 169 (RNF169) is a probable E3 ubiquitin-protein ligase that acts as a negative regulator of the repair of double-strand breaks (DSBs) following DNA damage. RNF169 is recruited to DSB repair sites by recognizing and binding ubiquitin catalyzed by RNF168 and competes with TP53BP1 and BRCA1 for association with RNF168-modified chromatin, thereby acting as a negative regulator of DSB repair. This gene is mapped to 11q13.4.