_:vb50942814 . _:vb50942814 . _:vb50942814 . _:vb50942814 . _:vb50942814 . _:vb50942814 "url:https://www.ncbi.nlm.nih.gov/pubmed/17701905"^^ . _:vb50942814 "A cataract that has_material_basis_in heterozygous mutation in the CHMP4B gene on chromosome 20q11."^^ .