Clinical and hematological evaluation of two δ0 δ0 - thalassemia homozygotes

Abstract

Two homozygous δ0 β0-thalassemia patients, one with the GγAγ type and the other with the Gγ type, and their heterozygous parents are described. Red cell indices among the heterozygotes with the GγAγ type of δ0β0-thalassemia were markedly different from those in heterozygotes with the Gγ type. However, the imbalance in in vitro hemoglobin synthesis was quite similar in the two heterozygous conditions. The same was observed for the homozygous patients; the in vitro chain synthesis was severely imbalanced as seen in β-thalassemia major. The clinical and some of the hematological findings were milder in the Gγ-δ0 β0-thalassemia homozygote than in the GγAγ - δ0 β0-thalassemia homozygote. The death of a sibling of the Gγ - δ0 β0-thalassemia homozygote with a diagnosis of thalassemia major suggests that both types of δ0 β0 -thalassemia could follow a severe clinical and hematological course. The discovery of the Gγ type of δ0 β0-thalassemia in a Turkish child shows that two types of δ0 β0 - thalassemia can be found in that country. Differentiation between the two types can only be made through structural analyses of Hb F.