Congenital dyserythropoietic anemia (CDA) is an autosomal recessive disorder that affects erythropoiesis. Due to dyserythropoiesis (abnormal red blood cell formation), erythroblasts (immature red blood cells) present in patients with CDA has an odd shape and extra nuclei which cannot develop into functional normal red blood cells. The clinical features of CDA include fatigue, weakness, pale skin, and further complications. CDA consists of three main forms: type I, type II, and type III. CDA type I is distinguished by moderate to severe anemia. It is diagnosed during childhood or adolescence, though some cases can be identified prenatally. Patients with CDA type I suffer from jaundice, hepatosplenomegaly, and iron build-up, which can lead to tissue and organ damage, arrhythmia, cirrhosis, diabetes, and congestive heart failure. Certain CDA type I cases are also reported with skeletal anomalies affecting the fingers and/or toes.
Congenital dyserythropoietic anemia (CDA) type I is associated with mutations in the CDAN1 (Codanin 1) gene, which encodes a protein involved in chromatin assembly and protein localisation.