Abstract
Hemoglobin Q- India (alpha) 64 Asp → His is an alpha chain variant which is generally found in heterozygous state and presents normal hematological blood picture. Here we report a rare case of HbQ-India with a thalassemic phenotype that has been analyzed using a combination of mass spectrometry, gene sequencing and PCR analysis. This combined analyses revealed the HbQ variant to be associated with a beta chain mutation, IVS 1-1 [G>T]. Though HbQ has earlier been reported with thalassemic trait using different techniques, this is the first report of a compound α and β chain Hb heterozygous mutant involving HbQ and IVS1-1 being validated using Mass Spectrometry and Reverse dot blot hybridization.
Key Words: Hemoglobin Q, Mass Spectrometry, Intervening sequence, Reverse dot blot hybridization, Amplification Refractory Mutation System
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