FGF4 and neoplasm: Conversely, GIST400 and GIST401 harboured only one duplicated segment in chr11, the one encompassing FGF4. Moreover, two fusion genes involving the terminal untranslated region (3′UTR) of FGF4 were detected in these two tumours: FGF4-3UTR was fused with the intergenic region upstream of CCND1 in GIST401 and with the upstream region of AP003555.2 in GIST400.