The retinoblastoma protein family consists of three proteins (pRB, p107 and p130; also known as RB1, Retinoblastoma-like 1 and Retinoblastoma-like 2 (RBL1-2), respectively) that share significant homology, yet only pRb is found frequently mutated in cancer (6). The gene discussed is RBL2; the disease is cancer.