The term congenital dyserythropoietic anaemia (CDA) designates a group of rare but well defined erythrocytic disorders. Type I is defined by macrocytosis and megaloblastic changes of the bone marrow cells. Two unrelated children with CDA are described with associated defects: absence of nails and short or absent phalanges, polysyndactyly of the fourth metacarpal. One of them had also areas of depigmentation.
Conclusion: The association of congenital dyserythropoietic anaemia with morphological defects of hands and feet is suggested to constitute a new syndrome caused by a single morphogenetic gene.