Additional file 2: Fig. S1. Structure and RNA-seq analysis of human, chimpanzee, and rhesus PRSSLY pseudogenes. Fig. S2. Phylogenetic analysis of PRSSLY nucleotide sequences. Fig. S3. Confirmation of X-linkage of PRSSLY in marsupials. Fig. S4. Phylogenetic analyses of PRSS family amino acid sequences. Fig. S5. Sequence conservation across PRSSLY gene sequences. Fig. S6. Analysis of synonymous (Ks) and non-synonymous (Ka) substitution rates across PRSSLY. Fig. S7. Expression of human PRSS homologs across tissues. Fig. S8. Gene expression analysis of PRSSLY in purified male germ cells and germ-cell-depleted testis. Fig. S9. Four CRISPR-induced mutations in mouse PRSSLY. Fig. S10. Testis weights of control and Prssly mutant mice. Fig. S11. Testis histology of control and Prssly mutant mice. Fig. S12. Litter sizes in Prssly mutants and controls.