In this cross-sectional study, we aimed to determine whether polymorphisms in the key repair enzyme pathways BER (XRCC1), NER (ERCC2, ERCC5), HR (RAD52, Mre11, NBN), and NHEJ (XRCC4), which have been previously associated with HBV infection and/or susceptibility to cancer, interfere with HBV-induced liver cirrhosis. The gene discussed is NBN; the disease is cirrhosis of liver.