. "familial erythrocytosis 4"@en . "disease_ontology"^^ . "OMIM:611783"^^ . "ECYT4"@en . "DOID:0080339"^^ . . . "A primary polycythemia that has_material_basis_in autosomal dominant inheritance of gain-of-function mutations in the EPAS1 gene on chromosome 2p21."^^ .