A Novel α-Globin Chain Variant, Hb Nanchang [HBA2: c.46G>A, Codon 15 (GGT>AGT) (Gly→Ser)], Detected by Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry

Abstract

Here we report a new α chain variant accidentally discovered during Hb A_1c measurement by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) that revealed the presence of a variant α chain with a mass of 15155 Da. However, this hemoglobin (Hb) variant cannot be detected by the first-line methods such as cation exchange high performance liquid chromatography (HPLC) and capillary electrophoresis (CE). Sanger sequencing confirmed the presence of a heterozygous missense mutation [HBA2: c.46G>A, codon 15 (GGT>AGT), (Gly→Ser)]. The theoretical mass difference (30 Da) due to the substitution of amino acid glycine to serine matched the actual measured mass difference (29 Da). As this is the first report of the mutation, we named it Hb Nanchang after the place of residence of the proband.

Keywords:

• Hb A_1c
• Hb Nanchang (HBA2: c.46G>A)
• Matrix-assisted-laser-desorption ionization-time of flight mass spectrometry (MALDI-TOF)
• mass spectometry (MS)

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.

Additional information

Funding

This study was supported by Guangdong Medical Science Foundation [B2021064].