Globin Chain Synthesis in Sicilian Thalassaemic Subjects

Summary. Globin synthesis has been studied in two homozygous β‐thalassaemic subjects, in two homozygous βs patients and in four subjects doubly heterozygous for the two β‐gene abnormalities. All the patients considered were of Sicilian origin. The results obtained can be summarized as follows: Decreased β‐globin synthesis and excess of α‐globin synthesis was found in all the β‐thalassaemic subjects examined. This finding further suggests the existence of different genetic determinants for the Cooley's disease, directing the synthesis of different amounts of β‐globin in different thalassaemic populations. Ratio of 3Hα to 3H counterpart globins was higher than 1 in the initial stages of the incubation, both in the total lysates and in purified haemoglobins. These ratios, after 8 hr of incubation, decrease to values lower than unity. These results suggest that the excess of newly synthesized α‐molecules flows initially from the polyribosomes to the haemoglobins, and then more slowly, to a ‘stromal’α‐pool. Combination of the excess α‐molecules with Hb S in the double hetero‐zygotes considered. This combination indicates that the β‐thalassaemia and the βs genes are present within the same cellular clone.