[Research progress of circular RNA in male reproductive disorders]

Male reproductive disorders have emerged as a global issue. Infertility affects 8% to 12% of couples of childbearing age. The sperm concentration and total sperm count of men have shown a significant downward trend over the past four decades, with a decrease of more than 50%. Male reproductive disorders are related to multiple factors. Circular RNA (circRNA) is a type of non-coding RNA with covalently closed circular structures. It is involved in a variety of biological processes, including gene expression regulation, protein function regulation and epigenetic regulation. Studies have shown that there are differences in the expression of circRNA in the testicles and semen between infertile patients and healthy people, suggesting that circRNA is involved in the process of spermatogenesis, and its abnormal expression is associated with male infertility. This review takes the biological functions of circRNA as the starting point and summarizes the research progress of circRNA in male reproductive disorders. CircRNA has the potential to serve as a novel biomarker due to its conservative, special structure and tissue specificity, which provides a new strategy for the clinical diagnosis of male reproductive disorders.