These interactions, excluding the weak interaction between MUTYH and XRCC1 (rs1799782), may shape a linear network topology in the form of MUTYH-OGG1-XRCC1-PARP1 (Figure 2A), although the three interaction links were observed in two different studies for different cancers (two links in Polish colorectal cancer [9] and one in Chinese gastric cancer [17]). The gene discussed is XRCC1; the disease is gastric cancer.