Rapid Molecular Diagnosis of Hemoglobin Variants by RT-PCR of Reticulocyte mRNA and Direct Sequencing

Abstract

We have developed a rapid and simple approach for the molecular characterization of hemoglobin variants by a one-step reverse transcription-polymerase chain reaction of reticulocyte mRNA and direct sequencing of the product. This method can selectively amplify the α.1- or α.2-globin gene or the β-globin gene transcript. The amino acid substitution of Hb G-Taichung is due to a G→C mutation at codon 74 of the α1-lobin gene, that of Hb J-Meinung to a G→A substitution at codon 56 of the β-globin gene, and that of Hb Kaohsiung (or New York) to a T→A substitution at codon 113 of the β-globin gene. The amplified segment encompassed the sequence from upstream of the initial codon behind the Cap site to downstream of the terminal codon before the polyadenylation addition signal. Hence, all hemoglobin variants should be able to be characterized by this approach.