In murine metastatic retinoblastomas lacking Rb and p130, array CGH revealed recurrent whole chromosomal gains at chromosome 1 (with synteny to the minimal region of gain in human retinoblastoma at human 1q31-32) and 12 (with synteny to the minimal region of gain at human 2p24) [68]. Here, RBL2 is linked to retinoblastoma.