Consensus sequence and predicted mutation landscape of the signal peptide of GDF9. A. Multiple alignment of 9 mammalian sequences, and definition of the consensus, subsequently used as a reference sequence. The asterisks denote strictly conserved amino acids. Note that in position 5, N and S are equiprobable. B. The alignment between the consensus and the Papio anubis (Pa) sequence shows that only two positions are divergent. For the sake of simplicity, N is kept at position 5 (underlined), because it is present in the P. anubis sequence. The potential impact of the mutations (put in the context of the consensus) on the signal peptide function is represented underneath: a black dot symbolizes each mutation or their combination, and the labels are color-coded according to the signal peptide probabilities predicted by Phobius (as % with respect to the score of the consensus with no mutations, using the sequence length displayed in the figure).