Example of RT-PCR analysis of exon 45–55 skipping in myotube cultures from an exon 48–50 deletion patient. Each AON combination was tested in 6 wells and results were compared to 6 untreated wells. Exon 45–55 skipping can be seen in untreated cells (upper panel, lanes 1, 2, 4–6, indicated by a an asterisk) as well as cells treated with the cocktail of AONs (middle panel, lanes 1, 4–6) and the linked AON (lower panel, lanes 1, 3 and 5). In addition, exon 45–53 and 55 skipping (upper panel, lane 3, middle panel, lane 2) and exon 45–53 skipping (middle panel, lane 2) were observed. Additional bands were too faint to allow identification by sequence analysis. The band slightly higher than the 45–55 skip product (e.g. lower panel, lane 4) is a PCR artifact arising from false annealing of somewhat similar sequences in exons 44 and 55. Exon 45–55 skip products were verified by sequencing.