A Novel Hemoglobin Variant Hb Liaobu [α107(G14)Val→Leu, HBA2: c.322G>C] Detected by Matrix-Assisted Laser Desorption Ionization-Time-of-Flight Mass Spectrometry

Hemoglobin. 2021 Sep;45(5):341-344. doi: 10.1080/03630269.2022.2036186. Epub 2022 Mar 24.

Abstract

We here describe a novel hemoglobin (Hb) variant, Hb Liaobu [α107(G14)Val→Leu, HBA2: c.322G>C], in a Chinese family. The structurally abnormal α chain variant could not be detected using capillary electrophoresis (CE) and was subsequently characterized by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS), and further confirmed by reversed phase high performance liquid chromatography (HPLC). Sanger sequencing revealed a novel base mutation on the α2-globin gene and RNA analysis by reverse transcription polymerase chain reaction (RT-PCR) showed the presence of an abnormal HBA transcript. The isopropanol stability test indicated the stable state of this structural Hb variant. In conclusion, a new Hb variant, Hb Liaobu, was discovered and characterized. It was proven to be a nonpathogenic variant. Our study resolved the confusion in the clinical diagnosis of individuals with this novel Hb variant in this family.

Keywords: Hb Liaobu; hemoglobin (Hb) variant; mass spectrometry (MS); thalassemia; α-Globin gene.

MeSH terms

  • Electrophoresis, Capillary
  • Hemoglobins, Abnormal* / analysis
  • Hemoglobins, Abnormal* / genetics
  • Humans
  • Lasers
  • Mass Spectrometry
  • Mutation
  • alpha-Globins / analysis
  • alpha-Globins / genetics

Substances

  • Hemoglobins, Abnormal
  • alpha-Globins