Molecular analysis of a t(II;22) translocation junction in a case of Ewing's sarcoma

✍ Scribed by Dr. Thounaojam Bhagirath; Dr. Syuiti Abe; Takayuki Nojirna; Michihiro C. Yoshida

• Book ID: 102846839
• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 622 KB
• Volume: 13
• Category: Article
• ISSN: 1045-2257
• DOI: 10.1002/gcc.2870130209

✦ Synopsis

Polymerase chain reaction (PCR)-directed sequence analysis was performed to characterize the genomic and cDNA breakpoint junctions of t( I I ;22) (q24;q 12) translocation in a case of Ewing's sarcoma, in which the EWS gene located on chromosome 22 is rearranged with the FUI gene located on chromosome I I. RNA-PCR revealed the novel chimeric product of EWSIFU I gene on the derivative chromosome (der) 22, resulting from a probable fusion of EWS exon 7 to FUI exon 9. Sequencing of the PCR-amplified genomic fragments of the fusion genes showed that the breakpoints on der(22) occurred in EWS intron 7 and, most probably, in FUI intron 8. Those of the untranxribed counterpart on der( I I) were located in the same FUI intron and in EWS exon I I, with deletion of a considerable amount of sequences from both genes. These findings indicate asymmetric junction at the molecular level in the present t( I I ;22). None of the reported conserved sequences that mediate other cancer chromosome translocations was observed around the genomic junctions. Instead, a palindromic hexamer 5'-GCTAGC-3' was found to flank the breakpoints of both genes on der( 22), which may have a functional significance in the genesis of the t( I 1;22).