Based on limited published evidence, CFAP157 is a cilia and flagella-associated protein specifically required for spermatogenesis, flagellum morphogenesis, and sperm motility 1. It functions in sperm axoneme assembly and microtubule binding at the ciliary basal body, likely suppressing supernumerary axoneme formation to ensure proper ultrastructure. CFAP157 was identified as a candidate gene variant in congenital heart disease patients with laterality defects 2, and its expression appears associated with ciliated epithelial cell populations in respiratory tissues.