_:vb50943010 "A retinitis pigmentosa that has_material_basis_in mutation in the TOPORS gene on chromosome 9p21."^^ . _:vb50943010 . _:vb50943010 . _:vb50943010 . _:vb50943010 . _:vb50943010 "url:https://www.ncbi.nlm.nih.gov/pubmed/17924349"^^ . _:vb50943010 .