Long description

Three diagrams of haemoglobin molecules.

Left – no mutation, full haemoglobin. A non-carrier of thalassaemia. A diagram of a haemoglobin molecule showing four globin chains, here conventionally arranged at the four corners of a square. Each globin chain is a folded, elongated “sausage” in a different shade of blue. Attached to each globin chain is a haem moiety, shown as a yellow disc with “Fe” (iron) on it. Two of the globin chains are labelled α, and two β.

Centre – one mutation – less haemoglobin. β-thalassaemia carrier without illness, but with less haemoglobin (slight anaemia). A diagram of a haemoglobin molecule as in (left) above, but with one of the β-globin chains missing.

Right – two mutations – no β-globin. β-thalassaemia major patient with severe anaemia. A diagram of a haemoglobin molecule as in (left) above, but with both β-globin chains missing.