The testis, or testicle, is one of typically two oval-shaped endocrine glands that form part of the male reproductive system. The testes are the male homologues to the female ovaries, and their main functions are the production of sperm (spermatogenesis) and of male sex steroid hormones (androgens), primarily testosterone.

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News and Comment

  • Comments & Opinion |

    Some chemotherapeutic agents can induce distinct mutational signatures in healthy cells in patients with cancer. The effect of such mutational signatures on spermatogenesis is not fully understood but is of great clinical importance for counselling patients diagnosed with cancer planning to start a family after treatment.

    • Ari P. Bernstein
    • , Justin Loloi
    •  & Ranjith Ramasamy
  • News & Views |

    The extent, duration and causes of alterations in the testes caused by SARS-CoV-2 are unclear. A new study has documented the effects of SARS-CoV-2 infection on the testes of a golden Syrian hamster model; however, the relevance of these findings to non-severe human infection is questionable.

    • Nathalie Dejucq-Rainsford
  • News & Views |

    Trends in vasectomy use are controversial, but rates might be declining over time. Several factors could contribute to this apparent decrease, which warrant consideration before definitive conclusions are made.

    • Nahid Punjani
    •  & Marc Goldstein
  • News & Views |

    Evidence for the existence of racial disparities in semen parameters is increasing, exemplified by a recent study in men from white, Black and Asian populations. However, reference standards for semen parameters might not account for these disparities.

    • Francesco Del Giudice
    •  & Michael L. Eisenberg
  • News & Views |

    A new study reveals that a high-sugar diet acutely alters human sperm small RNA profiles after 1 week and that these changes are associated with changes in sperm motility. This rapid response by sperm to nutritional fluctuation raises intriguing questions regarding the underlying mechanisms and the potential effects on offspring metabolic health.

    • Ying Zhang
    •  & Qi Chen