Congenital dyserythropoietic anemiatype I (CDA I) is a hematologic disorder of erythropoiesis characterized by moderate to severe macrocytic anemia occasionally associated with limb or nail deformities and scoliosis. The disease is congenital dyserythropoietic anemia type 1 (Monarch Disease Ontology id MONDO_0020337). Also known as: CDA I, CDA type 1, CDA type I.