PEX3 and male infertility: In particular, the germ cell- but not Sertoli cell-specific deletion of a testis-preferential peroxisomal protein, PEX3, led to the absence of PEX3-dependent peroxisomes in spermatids and increased levels of ROS in germ cell-specific knockout testes, which resulted in the formation of MGCs composed of spermatids, defects in spermiogenesis, and eventually male infertility.