Thai (delta beta)0-thalassemia and its interaction with gamma-thalassemia.

A variant of Southern Italian (delta beta)0-thalassemia is described in a women of Thai origin. The 3' breakpoint in Thai (delta beta)0-thalassemia is located about 1 kb upstream to that in Southern Italian (delta beta)0-thalassemia and produces a smaller deletion of approximately equal to 12.5 kb. Hematological phenotype, particularly Hb F output, is similar to that found in G gamma A gamma(delta beta)0-thalassemia despite the presence of a coexistent gamma-thalassemia effect.