Globin gene mapping in normal Hb A2 types of beta-thalassaemia.

Globin-gene mapping of DNA from 13 families with normal Hb A2 beta-thalassaemia (both type 1 and type 2) failed to detect any difference from normal in their globin-gene arrangement. We conclude that deletions such as those responsible for gamma beta-thalassaemia or a 'silent' Hb Lepore are not responsible for this type of beta-thalassaemia in Greece.