Thalassemia (Hemoglobin H)
(a) α‐Thalassemia: Hemoglobin H disease (three α‐globin gene deletion).
The blood film shows marked hypochromic, microcytic cells with target cells and poikilocytosis.
(b) α‐Thalassaemia: haemoglobin H disease.
Supravital staining with brilliant cresyl blue reveals multiple fine, deeply stained deposits (‘golf ball’ cells) caused by precipitation of aggregates of β‐globin chains.