Figure 1. Schematic representation of gross deletions in the RB1 gene in patients with retinoblastoma. The promoter and exons 1–27 with flanking intronic sequences of RB1 are depicted; domain A and domain B and coding for the binding domain A/B pocket are shown. Bars represent partial (exons 13–17 in RB940) and whole gene (RB668, RB679, RB056, and RB219) deletions. Abbreviations: Uni, unilateral RB; Bi, bilateral RB.