Figure 4. Breakpoint junctions of USH2A deletions characterized by PCR amplification and sequencing. A: Exact breakpoints of deletion involving exon 14 of USH2A in patient RP-1622. B: Exact breakpoints of deletion involving exons 5-13 of USH2A in patient RP-838. C: Exact breakpoints of deletion involving exons 5-9 of USH2A in patient RP-1638. D: Exact breakpoints of deletion involving exons 22-29 of USH2A in patient RP-1678. IVS: Intervening sequence.