Fig. 4.

RT-PCR for SS18-SSX gene fusions. Rare fusion site for SS18-SSX2 fusion transcript (case 18) (a and b). a Gel electrophoresis of the RT-PCR product. Lane M, size marker; Lane 1, positive control; Lane 2, negative control; Lane 3, blank control; Lane 4, internal control (GAPDH); Lane 5, SS18-SSX1; Lane 6, SS18-SSX2; Lane 7, SS18-SSX4. b Partial nucleotide sequence of the SS18-SSX2 fusion transcript; the fusion sites (arrow) are involved in exon 9 of the SS18 gene (codon 366) and exon 5 of the SSX2 gene (codon 94). c SS18-SSX4 (case 24). The gel-electrophoresis demonstrates obvious SS18-SSX4, with clean lanes of SS18-SSX1 and SS18-SSX2