Cytogenetic/molecular abnormalities significantly influence the prognosis of patients with acute leukemia. Recently, two genes, p16 and p15, encoding two cyclin-dependent kinase inhibitor proteins of the INK4 family of Mr 15,000 and 16,000, respectively, have been localized to 9p21. Remarkably, the p16 locus has been found to encode a second protein, p14, known as p19 in mice, with a distinct r...