This possible mechanism is supported by our studies showing that more efficient deletion of RBP-J in renin-expressing cells results in a higher incidence of B-cell leukemia: in both SV and Bl6 strains, animals with two copies of Cre recombinase had a higher incidence of B-cell leukemia as well as a shorter latency to leukemia development. This evidence concerns the gene RBPJ and leukemia.