Hemoglobin Nigeria (α-81 Ser→CysJiA New Variant Associated With α-Thalassemia

Hematologic evaluation of a Nigerian obstetrical patient disclosed the presence of sickle-cell trait as well as evidence of a hemoglobin α-chain abnormality. Hemoglobins containing the variant α-chain were isolated by DEAE-cellulose column chromatography, and analysis of the purified α-chain demonstrated a ser→cys substitution at α-81. The abnormal α-chain represented approximately 45% of the total, and hemoglobins containing this α-chain appeared to have normal stability and functional properties. In addition to the abnormal hemoglobins that were identified in this patient, she also was found to have persistent microcytosis in the absence of iron deficiency, and the percentage of HbS in her erythrocytes was less than that usually present in individuals with sickle cell trait. These findings, together with a reduced α/β globin synthesis ratio from her peripheral blood reticulocytes, indicated the presence of α-thalassemia trait. Hematologic findings from members of the patient’s family suggest that an α-thalassemia gene may be linked to that of the structurally abnormal α-chain.