Background: Fusion of the collagen type I alpha 1 (COL1A1) gene with the platelet-derived growth factor B-chain (PDGFB) gene has been described in dermatofibrosarcoma protuberans (DFSP). Various exons of the COL1A1 gene have been shown to be involved in the fusion with exon 2 of the PDGFB gene. Objectives We examined the breakpoint of the COL1A1 gene using the tumour specimen from the patient with DFSP.
Methods: Reverse transcriptase-polymerase chain reaction (PCR) was performed using cultured DFSP tumour cells. Nucleotide sequence analysis was carried out using the PCR product to identify the breakpoint.
Results: The COL1A1-PDGFB fusion transcript was detected from the tumour specimen. Sequence analysis revealed that exon 18 of the COL1A1 gene was fused with exon 2 of the PDGFB gene.
Conclusions: This study identified a novel COL1A1 breakpoint, namely, exon 18 of the COL1A1 gene.