HOOK1 and spermatogenic failure 16: However, previous studies have only found a few genes associated with human acephalic spermatozoa syndrome, such as SUN5, PMFBP1, TSGA10, BRDT, HOOK1, DNAH6, and CEP112 (Li et al., 2017, 2018; Chen et al., 2018; Sha et al., 2018a,b, 2019, 2020; Ye et al., 2020; Mazaheri Moghaddam et al., 2021).