Diminished synthesis of an alpha chain mutant, hemoglobin I (alpha-16 lys leads to glu)

In patients heterozygous for abnormal hemoglobins there is usually less than 50% of the mutant hemoglobin present in peripheral blood. The synthetic rates of alpha-chain mutants compared to alpha(A) have not been reported to date. In this study the production of alpha(A)- and alpha(I)-chains has been measured in peripheral blood and bone marrow of two patients with approximately 30% hemoglobin I, an alpha-chain abnormality (alpha(16 lys --> glu)). The results suggest that the decreased amount of alpha(I) compared to alpha(A) is due solely to diminished biosynthesis of the alpha(I)-chains. The relative rates of synthesis of alpha(I)- and alpha(A)-chains are similar in both nucleated red cells and reticulocytes indicating that no change occurs during erythroid cell maturation which preferentially affects either alpha(I) or alpha(A) production.

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