RSPH9 and Infertility: Here, we reported the fertility status of three individuals, two of them carrying pathogenic variants in RSPH1 and one in RSPH9. All presented with associated infertility due to asthenozoospermia (Supplementary Videos S4–S6) with (OP-3957 II1) or without (OP-3257 II1 and OP-2491 II1) morphological abnormalities of the sperm (Figures 4, 5), providing novel evidence for the functional conservation of both RSPH1 and RSPH9 also in sperm flagella.