A Novel Hemoglobin Variant Found on the α1 Chain: Hb KSVGH (HBA1: p.Lys57_Gly58insSerHisGlySerAlaGlnValLys)

Abstract

Glycosylated hemoglobin (Hb A_1C) is a crucial indicator for the long-term control and the diagnosis of diabetes. However, the presence of hemoglobin (Hb) variants may affect the measured value of Hb A_1C and result in an abnormal graph trend and inconsistency between the clinical blood sugar test and Hb A_1C values. In this study, laboratory data of 41,267 patients with diabetes were collected. The Hb A_1C levels and the graph results were examined. We identified 74 cases containing abnormal Hb A_1C graph trends. The conducted blood cell counts and capillary Hb electrophoresis were used to analyze Hb variants. We also determined gene variation for the Hb variants by a sequence approach. Fifteen different types of Hb variants were identified in this study. Among these, we found a novel variant in which the α1 subunit of Hb showed an insertion of 24 nucleotides (nts) between the 56th and 57th residues. We named this novel variant Hb Kaohsiung Veterans General Hospital (Hb KSVGH) (HBA1: p.Lys57_Gly58insSerHisGlySerAlaGlnValLys).

• Erythrocytosis
• glycosylated hemoglobin (Hb A_1C)
• hemoglobin (Hb) variant
• Hb Kaohsiung Veterans General Hospital (Hb KSVGH)
• high oxygen affinity

Declaration of interest

This study was supported by grants from the Kaohsiung Veterans General Hospital (VGHKS100-039) and from the Veterans Affairs Council of Executive Yuan of Taiwan (VAC100-C11). The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.