Fig. 3: Design of the LD-RT-PCR assay.

A Schematic representation of the assay for the detection of fusion transcripts of ALK, ROS1, RET and MET. LD-RT-PCR probes were designed for 91 different genes to target 87 rearrangements. For most genes, multiple probes were designed on different exons to target different transcripts that result from the distribution of the genomic breakpoints within different introns. B Principle of the detection of MET exon 14 skipping by the LD-RT-PCR assay. Specific probes of the 3’ part of MET exon 13 and 14 and of the 5’ part of MET exon 14 and 15, with various lengths. When no MET exon skipping was present, two different PCR products of 52 + 49 base pairs and 55 + 53 base pairs were observed. When a MET allele harboring exon 14 skipping was present, a third PCR product with a length of 52 + 53 base pairs was observed. bp base pairs, F fluorophore, LD-RT-PCR ligation-dependent reverse transcription polymerase chain reaction.