A Rapid Single-Tube Multiplex Polymerase Chain Reaction Assay for the Seven Most Prevalent α-Thalassemia Deletions and ααα^{anti 3.7} α-Globin Gene Triplication

Abstract

α-Globin gene triplications may exacerbate the α chain and β chain imbalance in β-thalassemia (β-thal) and may compensate for the effect of α-globin gene deletion in α-thal. Identification of an α-globin gene triplication is, therefore, valuable in predicting the clinical phenotype of the thalassemias. To be able to detect α-globin gene triplications, we have modified an existing multiplex polymerase chain reaction (PCR) assay for the seven most prevalent α-globin gene deletions by incorporating two triplication-specific primers and concurrently substituting one of the original primers by a newly designed primer. This modified multiplex PCR assay was evaluated by performing the assay on archival DNA samples and on peripheral blood samples from 163 suspected thalassemia cases. It was found to function properly. Our assay thereby represents the first multiplex PCR assay that can detect both the seven most prevalent α-globin gene deletions and the ααα^{anti 3.7} α-globin gene triplication in a single-tube reaction.

Keywords:

• Thalassemia
• ααα^{anti 3.7} α-Globin gene triplication
• Single-tube multiplex polymerase chain reaction (PCR)
• Assay

ACKNOWLEDGMENT

The authors wish to thank Dr. Cornelis L. Harteveld (Department of Human and Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands) for providing some of the DNA samples and the – –^THAI deletion clone.