_:vb50943044 . _:vb50943044 "url:https://www.ncbi.nlm.nih.gov/pubmed/21549338"^^ . _:vb50943044 . _:vb50943044 . _:vb50943044 . _:vb50943044 . _:vb50943044 "A retinitis pigmentosa that has_material_basis_in mutation in the PRPF6 gene on chromosome 20q13.33."^^ .