Identification of one or two α-globin gene deletions by isoelectric focusing electrophoresis.

OBJECTIVES To investigate the utility of isoelectric focusing electrophoresis (IEF) for identifying patients with α-thalassemia, which results from the deletion of 1 or more of the α-globin genes. METHODS Samples were selected based on their hemoglobin H (HbH) concentration observed using IEF. The samples were analyzed for the most common α-globin gene deletions using molecular analysis. RESULTS α-Globin gene deletions corresponding to α-thalassemia trait or silent carrier were observed in all samples with the HbH less than 2% phenotype. The genotypes of the specimens with HbH greater than 5% were consistent with HbH disease, while the wild-type phenotype control samples showed a wild-type genotype. CONCLUSIONS Low concentrations of HbH can be detected in a patient with 1 or 2 α-gene deletions using IEF.