Haemoglobin-H Disease

Haemoglobin-H was first described in 1955 by Rigas, Koler, and Osgood. It differs from the other abnormal haemoglobins so far described in that its inheritance cannot be followed by electrophoresis in its heterozy- gous and homozygous forms. Usually in the haemo- globinopathies, adult haemoglobin (HbA) and the abnormal haemoglobin are present in approximately equal quantities in the heterozygous state. In the homozygous state all or nearly all the haemoglobin present is of the abnormal type, the patient showing the features of the appropriate disease. In patients with haemoglobin-H disease the proportion of abnormal haemoglobin found varies from about 10 to 35%. It is irregularly found in relatives of these patients. In both these respects it resembles the appearance of haemo- globin-F in thalassaemia. Clinically, haemoglobin-H disease is very similar to thalassaemia minor. Two cases of this rare disease are reported in which red-cell survival and marrow iron turnover have been studied.