Peptide binding motifs defined by HLA-DPB1 alleles/supertypes in relation to the TEL-AML1 junctional 9-mer core peptide (RIAECILGM) with a negatively charged E in the P4 peptide binding pocket. This peptide is known to bind to DPB1*0501. The homologous wild-type TEL and AML1G peptide sequences are shown for comparison. The peptide binding frame for RIAECILGM is numbered P1–P9. The TEL and AML1G peptides have been positioned so as to show the same amino acid sequences as present in TEL-AML1, but it is not known whether they have the same binding frame. Note that AML-1G shares six of the nine amino acids with TEL-AML1, including an E at P4. DPB1*0101 and 0501 are identical for PBP P6, P4 and P1, but differ for the P7 and P9 PBP. All other supertypes differ from GKD at P6, P4 and/or P1