PurposeI describe two siblings who have a novel congenital bone marrow failure syndrome with myelodysplastic features without progression to malignancy for 13 and 20 years, respectively.Patients and MethodsMale and female siblings were evaluated for chronic anemia and intermittent bruising.ResultsBoth patients had been anemic from birth, one carrying a diagnosis of Diamond-Blackfan anemia and the other an idiopathic marrow failure syndrome. Both patients had a platelet function defect, mild pancytopenia, and bone marrow examination showed hypoplasia with myelodysplasia that did not fit a French-American-British classification. Neither patient had Fanconi's anemia, and the family history was negative.ConclusionsThis is the first report of a novel syndrome of congenital bone marrow failure and myelodysplasia.