Homozygous β thalassaemia in Liberia

Abstract

The clinical and hematologic findings in 19 Liberians probably homozygous for β thalassaemia are described. The hemoglobin patterns were similar with Hb F levels in the 30 to 50% range and a raised level of Hb A2 and, although the clinical severity varied widely, over half the cases were symptomless and even the more severely affected ones showed a milder picture than that found in Mediterranean races. Hemoglobin synthesis studies carried out on three homozygotes and two heterozygotes indicated a variable degree of globin chain imbalance. The reasons for the mild course of the disease in Liberians and other African races are discussed; it is likely that the β thalassaemia genes in these populations are different from those in other racial groups. It is noted that all persons in this study belong to tribes which have a low incidence of the sickle cell gene.