Congenital dyserythropoietic anemia type III.

BACKGROUND AND OBJECTIVES: Congenital dyserythropoietic anemia type III (CDA-III) is a group of very rare disorders characterized by similar bone marrow morphology. The clinical picture is characterized by hemolytic anemia and dramatic bone marrow changes dominated by active erythropoiesis with big multinucleated erythroblasts. The aim of this review is to describe the clinical manifestations, laboratory findings, and management CDA-III. EVIDENCE AND INFORMATION SOURCES: The present review critically examines relevant articles and abstracts published in journals covered by the Science Citation Index and Medline. The authors have performed several studies on CDA-III. STATE OF ART AND PERSPECTIVES: The clinical and laboratory manifestations of CDA-III indicate that the gene responsible for it, which has been mapped to chromosome 15q22, is expressed not only in erythroblasts during mitosis but also in B-cells, and in cells of the retina. Preliminary results indicate genetic and phenotypic similarities between a Swedish and an American family, both with an autosomally dominant inherited form of CDA-III. It is possible that the genetic lesion is identical in these families, but the different phenotypes and modes of inheritance reported among some other cases of CDA-III are probably the results of other genetic lesions. At present, the function of the gene responsible for the Swedish (V sterbotten) variant of CDA-III (CDAN3) is unknown and it is an important goal to characterize and clone this gene in order to study its function.