Globin Chain Synthesis is a Useful Complementary Tool in the Differential Diagnosis of Thalassemias

Abstract

The present study aimed at differentiating rare types of heterozygous β-thalassemia (thal) with normal Hb A₂ values from α-thal in Iranian carriers by globin chain synthesis in addition to other hematological parameters. Our study groups consisted of 51 normal subjects, 24 heterozygous β- thalassemic subjects with high Hb A₂, 62 α-thal-2 subjects, 34 α-thal-1 subjects, six Hb H disease thalassemic subjects, 14 silent β-thal subjects with normal Hb A₂ values, five δβ-thal subjects and two subjects with an association of α- and δβ-thal (total = 198). Analysis of globin chains was performed by high performance liquid chromatography (HPLC). The results showed that the α/β ratio averages were close to the ones in the published literature, but with a greater standard deviation and a wider range.

Globin chain synthesis (GCS) could be valuable in differentiating between microcytosis produced by silent β-thal (heterozygous β-thal with a normal Hb A₂ level) and that caused by α-thal. Since the complex genotype/phenotype relationship can lead to diagnostic difficulties, GCS cannot be used as the only diagnostic tool for thalassemia carrier detection. Therefore, a combination of different tests for each patient is required.

Keywords:

• Thalassemia
• Globin Chain Synthesis (GCS)
• α/β Ratio

Notes

15. Traeger-Synodinos J, Old JM, Petrou M, Galanello R. Best practice guidelines for carrier identification and prenatal diagnosis of haemoglobinopathies. European Molecular Genetics Quality Network Workshop held on March 2 2002 in Manchester, UK; 1–13.