_:vb50938459 "The most common type of familial ALS that has_material_basis_in mutation in the SOD1 gene on chromosome 21."^^ . _:vb50938459 . _:vb50938459 . _:vb50938459 "url:http://en.wikipedia.org/wiki/Amyotrophic_lateral_sclerosis"^^ . _:vb50938459 . _:vb50938459 . _:vb50938459 .