Hemoglobin H is a tetramer made of four beta globin chains.

Hemoglobin H is a tetramer made of four beta globin chains. Hemoglobin H occurs when there is very limited alpha chain availability used to make normal hemoglobin A. Hemoglobin H forms in those affected with alpha thalassemia major as well as in people with the combination of two-gene deletion alpha thalassemia and hemoglobin Constant Spring.

Hematology

Which of the following combination of globin chains comprise Hemoglobin H?