Fig. 2

a) Representative RT-PCR reactions demonstrating predominant levels of 100 bp TrkAIII compared to 300 bp TrkA RT-PCR products in MCPyV positive (MCPyV⁺) MCCs grouped by individual patient (P) generated from TrkA exon 5–8 primers (Upper and middle RT-PCRs) plus exclusive 300 bp TrkA RT-PCR products generated from MCPyV negative (MCPyV⁻) MCC, BCCs, SCCs and normal skin samples, using the same primers. All reactions were performed using undiluted RT reactions from FFPE tissue RNAs (500 ng) (10 μl loads per lane). b Representative direct PCR sequence of the TrkAIII exon 5–8 splice junction in a RT-PCR fragment generated from a stage IV MCPyV positive MCC (patient 1 (i)), using the exon 3–8 primer set