AHCYL1 and neoplasm: Similar to the occurrence in the CSF1-S100A10 fusion gene, the novel CSF1 transcript 3′-UTR is replaced by a new exon located ∼48 kb downstream of CSF1 and 11 kb upstream of AHCYL1. Although only 3 TSGCT were available for study, the finding in all of them of a novel CSF1-S100A10 fusion gene or CSF1 transcript indicates the existence of a common pathogenetic theme in this tumor type: the replacement of the 3′-UTR of CSF1 with other sequences.