Uniprot Description An autosomal recessive blood disorder characterized by morphological abnormalities of erythroblasts, ineffective erythropoiesis, macrocytic anemia and secondary hemochromatosis. It is occasionally associated with bone abnormalities, especially of the hands and feet (acrodysostosis), nail hypoplasia, and scoliosis. Ultrastructural features include internuclear chromatin bridges connecting some nearly completely separated erythroblasts and an abnormal appearance (spongy or Swiss-cheese appearance) of the heterochromatin in a high proportion of the erythroblasts.