Homozygous βd` - and β⁺ - Thalassemia in Kurdish Jews and Arabs

Abstract

Chromatographic separation of labeled globin chains was performed on peripheral blood of 38 patients with homorygous β-thalassemia. In 11 patients globin synthesis was also studied in bone-marrow cells. The results showed β/α synthetic ratios in the common range of β⁺-thalassemia (from 0.11 to 0.39) in 16 out of 27 Kurdish Jews (59%) and in ten out of 11 Arabs (91%). In nine Kurdish Jews (33%) and in one Arab βd`-thalassemia was found. In a few patients from the latter group a very small peak was detected in the β region, which co-chromatographed with β-chains from non-thalassemic individuals, but apparently represents synthesis of a non-globin protein. In two affected siblings, synthesis of small amounts of β-chains was demonstrated in peripheral blood (β/α 0.018–0.025) and in one sample of bone-marrow cells (β/α 0.046). These ratios are lower than any previously reported in β<sup>+</sup>-thalassemia. Identification of the presumed β-peak in these patients was based on an approximate tenfold increase in β/α, γ/α and δ/α synthetic ratios measured in hemoglobin isolated by gel filtration. In eight pairs of siblings synthetic ratios were almost identical. β/α and β/α synthetic ratios were higher in bone-marrow cells than in peripheral blood. In bone-marrow cells γ-chain synthesis was lower, often resulting in a more marked chain inbalance (non-α versus α) than in peripheral blood particularly in patients with βd`-thalassemia.