Abstract
Hb Khartoum [β124(H2)Pro→Arg] was first identified during screening for hemoglobinopathies in Khartoum (1). The abnormal hemoglobin (Hb), which comprised approximately 30% of the total Hb, had an electrophoretic mobility similar to Hb S. Although theoretically the replacement of proline by arginine might be expected to produce significant alteration in the configuration of the β-globin chain, there was no laboratory evidence of Hb instability.