CRISPR/Cas9-mediated genome editing reveals six testis-enriched genes dispensable for male fertility in mice

The genetic landscape of male infertility is highly complex. It is estimated that at least 1000-2000 genes are involved in human and mouse infertility. Although functional analyses have been performed on hundreds of genes, many others still have unknown functions. Generating gene-editing mice is a powerful tool for exploring whether a given gene is essential for male reproduction <i>in vivo</i>. In this study, we investigated the function of six genes, <i>Efcab7</i>, <i>Tekt3</i>, <i>Mlf1</i>, <i>Rp1l1</i>, <i>Agbl2</i>, and <i>Tmsb15a</i>, using the CRISPR/Cas9 system. Mating tests with mutant mice revealed that all six genes are dispensable for male fecundity when individually ablated. Meanwhile, phenotypic analyses of testicular appearance and weight, testis and epididymis morphology, and sperm motility parameters in these six mutant mice also showed no significant differences compared with wild-type mice. In summary, our results suggested that these six genes could be deprioritized for other researchers when they are interested in their roles in male infertility, thereby preventing duplicative research efforts.