Care of patients with haemoglobin abnormalities: history and biology.

Haemoglobinopathies refer to a range of genetically inherited disorders of red blood cell haemoglobin and include sickle cell disorders and thalassaemias. They occur most commonly in populations whose ancestors come from Africa, Asia, Mediterranean Islands, and the Middle and Far East. Haemoglobin (Hb) abnormalities (or haemoglobinopathies) are caused by (i) abnormalities of the protein structure; (ii) imbalanced globin chain production owing to reduced rate of synthesis of normal a or b globin chains; or (iii) a combination of the two. This article will focus on the biological basis of sickle cell disorders and will discuss the history and pathology of the conditions.