USP9Y and male infertility: This included Usp26 itself, Dazl, which encodes an RNA-binding protein that is essential for gametogenesis in both males and females (18), Usp9y, a Y-linked gene encoding a deubiquitylase associated with male infertility (19) and Dppa3, a primordial germ cell (PGC)-specific protein (20) (Fig. 5C).