The IGKC gene mutation rs232230 (C- > G) (IGKC*04 in the IMGT database) results in a nonsynonymous variant (V- > L) that is a risk factor in Helicobacter pylori infection in gastric cancer and age in breast cancer (odds ratio 1.64 and 1.94, respectively) [48]. This evidence concerns the gene IGKC and breast cancer.