Characterization of PAR1 deletion centromeric to CRLF2 and PCR detection of the P2RY8-CRLF2 fusion. (A) Representative log₂ ratio SNP 6.0 microarray DNA copy number data for 5 samples with PAR1 deletions. SNP array data derived from matched normal DNA is indicated by “N” and the leukemic sample with “T.” The black box highlights the region of PAR1 deletions. (B) RT-PCR demonstrating the fusion transcript of P2RY8 and CRLF2. Full-length cDNA transcripts were subjected to PCR with primers from P2RY8 and CRLF2 to generate the fusion products. (C) Genomic PCR of the chromosomal breakpoints joining CRLF2 and P2RY8. (D) Sequence of the RT-PCR product showing the junction of exon1 of P2RY8 with exon 1 of CRLF2. P2RY8 exon 1 is noncoding. (E) Germline sequence of the breakpoint. The exact junction of 5′ flanking sequence of CRLF2 to intron 1 of P2RY8 is shown. Several nonconsensus nucleotides are present at the junction.