_:vb50950283 . _:vb50950283 . _:vb50950283 . _:vb50950283 "url:https://www.genome.gov/Genetic-Disorders/Klinefelter-Syndrome"^^ . _:vb50950283 "A chromosomal duplication syndrome that is characterized by infertility and that has_material_basis_in an extra X chromosome in cells in men."^^ . _:vb50950283 "url:https://ghr.nlm.nih.gov/condition/klinefelter-syndrome"^^ . _:vb50950283 .