In rat models, silencing the HIF-1α gene in varicocele testes using the CRISPR/Cas9 gene editing technique significantly reduced the rate of apoptosis of spermatogenic cells and improved spermatogenic function by downregulating the VEGF/PI3K/AKT signaling pathway (Wang D. et al., 2020). The gene discussed is HIF1A; the disease is varicocele.