To address the immunogenic potential and the conflicting predictions for the recurrent RQCD1 mutation, 13mer peptides with shifted positioning of the exchanged amino acid (Supplementary Table 3) were synthesized and used to stimulate peripheral blood mononuclear cells (PBMCs), where available, from patients (n = 13) harboring melanomas with RQCD1 P131L. This evidence concerns the gene CNOT9 and melanoma.