PLD6 and Reduced sperm motility: Knockout of MitoPLD abolishes the majority of piRNA in male germ cells and resulted in transposon activation and arrest of spermatogenesis, characteristic phenotypes of piRNA pathway mutants (12).In this study, we measured the expression levels of MitoPLD in sperms of normozoospermic men and asthenozoospermia patients and found that MitoPLD protein was significantly downregulated in sperms of asthenozoospermia patients.