METTL3 and Infertility: Mice that lack Meioc are infertile, lacking germ cells that have reached the pachytene phase of meiotic prophase I. Notably, mice lacking Ythdc2 or Mettl3 display similar phenotypes, demonstrating infertility and defects in germ cells, which reach a terminal zygotene-like stage and undergo apoptosis [32, 45].