JMJD1C and male infertility: During the progress of our work, a precedent study on Jmjd1C-deficient mice was reported that showed the male infertility phenotype of Jmjd1C null-knockout mice due to the progressive reduction of germ cells after 3 months of age, indicating that JMJD1C contributed to the long-term maintenance of male germ cells [9].