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

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:

• α-Globin gene
• hemoglobin (Hb) variant
• Hb Liaobu
• mass spectrometry (MS)
• thalassemia

Acknowledgements

We sincerely thank the doctors at the prenatal diagnostic center of Dongguan Maternal and Children Health Hospital, Dongguan, Guandgong Province, PRC, for their involvement in collecting samples. We are grateful to the scientists in the genetics laboratory of Southern Medical University, Guangzhou, Guandong Province, PRC, for their help with this study.

Disclosure statement

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