EWSR1 and Ewing sarcoma: EWSR1, or Ewing’s sarcoma protein, forms fusions with a number of other proteins and serves as a transcriptional activator in human solid tumors like Ewing’s sarcoma and malignant melanoma.37 Information about its binding specificity is scarce, while SKA analysis of RNA Bind’n Seq data predicts G-rich elements.10 Our investigation lead to different varieties of poly(A) motifs (Figure 11(A) and(B)), which vary in relative dissociation constants−0.79≤logKDrel≤0.91 in log-KD, unspecific binding energy−4.18≤E0≤−0.55, and data likelihoods−2.2×109≥logP(D|M,E0)≥−4.50×109.