Here, to study the potential function of mTOR signaling in male germ cell development, we used chronic rapamycin treatment at approximately the same dose that was used to extend lifespan, and found that rapamycin-mediated prolonged inhibition of mTOR signaling causes male infertility, specifically, meiotic defects resulting from disruption in the meiotic silencing of sex chromosomes. This evidence concerns the gene MTOR and male infertility.