_:vb50943750 . _:vb50943750 . _:vb50943750 "url:https://www.ncbi.nlm.nih.gov/pubmed/9002666"^^ . _:vb50943750 . _:vb50943750 "An Usher syndrome type 1 that has_material_basis_in variation in the chromosome region 21q21."^^ . _:vb50943750 . _:vb50943750 .