Figure 1. Schematic representation of sequence mutations detected in 25 patients across the RB1 gene. Distribution of mutations in RB1 is described by mutation type in the promoter region, 27 exons, and splice sites of the gene. The functional domains A and B are shown; the numbers in boxes refer to the exons. The symbols denote ● missense, ▲splicing, ♦ nonsense and ■ frameshift mutations. A total of one partial and five whole gene deletions of RB1 are presented as the shaded bars. All mutations and gene deletions in the patients were detected in the heterozygous state.