_:vb50945733 . _:vb50945733 "url:https://pubmed.ncbi.nlm.nih.gov/31048344/"^^ . _:vb50945733 "url:https://pubmed.ncbi.nlm.nih.gov/31151990/"^^ . _:vb50945733 "A spermatogenic failure characterized by multiple morphologic abnormalities of the flagella resulting in ansence of forward motility in spermatozoa and infertility that has_material_basis_in homozygous or compound heterozygous mutation in SPEF2 on chromosome 5p13.2."^^ . _:vb50945733 . _:vb50945733 . _:vb50945733 . _:vb50945733 .