In B cell acute lymphoblastic leukemia (B-ALL), a number of PAX5 fusion proteins have been reported, including PAX5::ETV6, a fusion of the paired domain from PAX5 to a large portion of the ETV6 protein, which includes its helix-loop-helix and ETS domains [135]. The gene discussed is PAX5; the disease is B-cell acute lymphoblastic leukemia.