A 5-month-old boy with congenital hypoplastic anaemia and triphalangeal thumbs, known as the Aase syndrome, is described. In addition he had unilateral cleft lip and palate and abnormal dermatoglyphics. Only ten cases have been reported previously; these are reviewed. This case is the third patient reported to have the Aase syndrome who also has a cleft lip. Bone marrow cultures failed to stimulate production of erythropoietic precursors.