CDKN2A and neoplasm: ,123,139, 140, 141, 142, 143, 144, 145 The advantage of using tumor-prone mice, such as the Cdkn2a-deficient mice, is that they are highly sensitized to insertional mutagenesis and easily develop tumors, while in WT mice the tumor onset is only sporadic at best. Indeed, by transplanting vector-transduced Cdkn2a-deficient hematopoietic stem and progenitor cells into WT mice, it was possible to measure and compare the genotoxic potential of γ-RVs and lentiviral vectors (LVs) with self-inactivating (SIN) LTRs.142