_:vb50942949 . _:vb50942949 . _:vb50942949 . _:vb50942949 . _:vb50942949 . _:vb50942949 "A retinitis pigmentosa that has_material_basis_in mutation in the SEMA4A gene on chromosome 1q22."^^ . _:vb50942949 "url:https://www.ncbi.nlm.nih.gov/pubmed/16199541"^^ .