Thalassemia intermedia caused by heterozygosity for both β-thalassemia and hemoglobin saki [β14 (a11) leu→pro]

Abstract

The syndrome thalassemia intermedia can be the clinical expression of heterozygosity for different types of thalassemia, β‐thalassemia and hereditary persistence of fetal hemoglobin, β‐thalassemia and Hb‐Lepore, and in blacks it may even represent a true β‐thalassemia homozygote. This report describes thalassemia intermedia in a white male due to β‐thalassemia and an unstable hemoglobin. Chain‐synthesis studies showed an excess of β‐chain production over β‐chain production in the propositus and his mother but balanced chain synthesis in the clinically normal father, who is heterozygous for the unstable hemoglobin. The unstable hemoglobin was found to be β¹⁴ (A11) Leu→Pro, which has previously been described in a clinically normal African woman, and named Hb‐Saki. This hemoglobin is not distinguishable from Hb‐A on routine electrophoresis at alkaline or acid pH and tests for unstable hemoglobins are necessary for its detection. The increasing list of such hemoglobin variants and previous cases of heterozygosity for β‐thalassemia and unstable hemoglobins are reviewed.