Congenital dyserythropoietic anaemia (CDA) is a heterogeneous group of hematological disorders characterized by anaemia and distinct morphological abnormalities of erythroid precursors in the bone marrow. Patients with CDA present congenital and chronic anaemia of variable degree with a reticulocytosis not corresponding to the degree of anaemia (ineffective erythropoiesis), jaundice and frequently splenomegaly and/or hepatomegaly. Morbidity in CDA I, CDAII and other CDA patients that require continuous blood transfusions may be important due to iron overload complications that can be fatal if untreated.

Five classical types of CDAs (I-II-III-IV and XLTDA) have been defined on the basis of bone marrow morphology. CDA type II is the most common and well-defined form among CDAs. This working classification is nowadays still used in clinical practice. However, the identification of the mutated genes involved in the majority of CDA subgroups will improve the diagnostic possibilities and will allow a better classification of CDA patients, since at present, in many cases a final diagnosis is not achieved. On the other hand, there are several families that fulfill the general definition of CDAs, but do not conform to any of the classical CDA variants. Although several studies about molecular genetics and genotype-phenotype correlation have been performed in this field, the pathophysiology of CDAs is still an unsolved issue. Beyond to achieve a definitive diagnosis, knowing the genetic basis of CDA patients is valuable also for unravelling the pathophysiology of these disorders, as well as for guiding treatment (depending of the type of CDA, different treatments have been established).

The project is being carried out by 2 international teams that are world-wide recognized as experts in Congenital Dyserythropoietic Anaemia (CDA) and has the direct support of 2 patient associations (ADISCON and APU).