“…Recently, SUN5, PMFBP1, HOOK1, BRDT, TSGA10, and CEP112 have been found to be involved in the assembly of the HTCA, and mutations in these genes are associated with acephalic spermatozoa syndrome (Zhu et al, 2016(Zhu et al, , 2018Li et al, 2017;Chen et al, 2018;Sha et al, 2018Sha et al, , 2020aShang et al, 2018). Abnormalities of the axoneme and accessory structures mainly result in asthenozoospermia, which is associated with morphological flagellar defects such as abnormal tails, irregular mitochondrial sheaths, and irregular residual cytoplasm (Escalier and Touré, 2012;Tu et al, 2020). Previous studies have identified several flagella-associated genes, including AKAP3, AKAP4, TTC21A, TTC29, FSIP2, DNAH1, DNAH2, DNAH6, DNAH8, DNAH17, and DZIP1, that are involved in sperm flagellum biogenesis (Turner et al, 2001;Ben Khelifa et al, 2014;Martinez et al, 2018;Li Y. et al, 2019;Liu C. et al, 2019;Tu et al, 2019;Liu et al, 2020b;Lv et al, 2020;Sha et al, 2020b).…”