This section is dedicated to alpha (α-) thalassaemia.


HbH disease
α-thalassaemia Hydrops Foetalis
(=Hb Bart’s Hydrops Foetalis)

Many diseases in humans are caused by abnormalities in the blood and these are categorized according to the component of the blood which is affected: white cell diseases, platelet diseases and red cell diseases.

Haemoglobin disorders or haemoglobinopathies are a group of conditions affecting human blood – more specifically an important substance or protein called haemoglobin contained in the red blood cells, hence the name haemoglobin disorders or haemoglobinopathies.

Haemoglobin is a protein that consists of the alpha (α) and beta (β) parts or chains and which are in turn produced by the α-globin genes and β-globin genes respectively. Hence the diseases caused by haemoglobin abnormality either with regards to its production or its structure are divided into α-chain diseases (or α-globin gene) diseases, such as α-thalassaemia, and β-chain (β-globin gene) diseases, such as β-thalassaemia major and sickle cell disease. These genes are found on chromosomes 16 and 11 respectively, producing equal amounts of α and β chains respectively which match together to α2β2 to produce the normal adult haemoglobin (HbA, α2β2).