FF, characterized as failure to form two-pronucleus (2 PN) zygotes with morphologically normal gametes even with the help of ICSI, was a typical phenotype of infertile men carrying bi-allelic mutations in PLCZ1 (Mahutte and Arici, 2003; Torra-Massana et al., 2019; Yan et al., 2020). Here, PLCZ1 is linked to Infertility.