Mutations in several genes have been identified as being associated with asthenozoospermia, including the cilia and flagella associated protein (CFAP) family, such as CFAP43, CFAP44, CFAP45, CFAP58, CFAP65, CFAP69, and CFAP251 (3, 14, 15, 16, 17, 18, 19, 20, 21). The gene discussed is CFAP45; the disease is Reduced sperm motility.