Splicing signature and expression of the Q157Rdel variant in Q157R and Q157P patients. (A) The diagram shows 912 cassette exons with a dPSI value above 10% between Q157R/Q157P and U2AF35 wt patients with a Bayes factor ≥5 and confidence intervals not diverging more than 10% from the calculated PSI value. Plotted are the PSI values of these 912 cassette exons in patients with Q157R and Q157P mutation. Differentially spliced exons with dPSI higher or equal to 10% are shown in green for Q157P and red for Q157R. (dPSI) delta percent spliced in. (B) Comparison of PSI values of cassette exons obtained in cell culture (Fig. 2) by RT-PCR to PSI values in U2AF35 wt, Q157P and Q157R patients. (*) P < 0.05; (**) P < 0.01; (***) P < 0.001; (####) Bayes factor >100. (C) Overlap between U2AF35-dependent cassette exons in RNA sequencing of HEK293T cells (Fig. 3) and differentially spliced exons in Q157P/Q157R patients. (D) Comparison of alternative splicing in cell culture experiments to splicing observed in patients. dPSI values between wt and either Q157P or Q157R were calculated for the 70 overlapping targets (C) between cell culture and patient sequencing and plotted against each other. Correlation coefficients were calculated. (E) Identification of the Q157Rdel isoform in AML patients. Depicted is the number of reads of the Q157P, Q157R, Q157Rdel, and wt variants in U2AF35wt, Q157R, and Q157P patients as percent of total reads at that position. (F) Examples of differentially spliced exons in patients and cell culture where the Q157Rdel rather than the Q157R mutant might regulate splicing in patients. 3′ splice sites of the alternative exons are depicted below the graphs. (#) Bayes factor >3, (##) Bayes factor >20, (####) Bayes factor >100.