Reverse transcription-PCR and DNA sequence analyses revealed that a part of exon 6 of EWS is fused in-frame to exon 2 of Oct-4 in these tumours, which indicated that an alternative form of EWS-Oct-4 exists owing to a variation in the locations of the EWS and Oct-4 genomic break points. Here, POU5F1 is linked to neoplasm.