%0 Journal Article
%T Hb Kalundborg [β79(EF3)Asp→Glu; HBB: c.240C>a], a Possible Low-affinity Hemoglobin Variant Detected during Hb A1c Measurement.
%A Ahmad-Nielsen EB
%A Szecsi PB
%A Bratholm PS
%A Petersen J
%A Glenthøj A
%J Hemoglobin
%V 46
%N 2
%D Mar 2022
%M 35920343
%F 0.822
%R 10.1080/03630269.2022.2079520
%X A previously unknown hemoglobin (Hb) variant was detected during measurement of glycosylated Hb (Hb A1c) after the introduction of a new high performance liquid chromatography (HPLC) apparatus. Subsequent DNA sequencing revealed a heterozygous single nucleotide substitution at codon 79 (C>A) on the β-globin gene changing an amino acid [β79(EF3)Asp→Glu; HBB: c.240C>A]. The new Hb variant was named Hb Kalundborg after the place of origin of the proband. Heterozygosity for this mutation appears to have no clinical significance in itself except for a possibly slightly lower oxygen affinity. However, it interferes with Hb A1c measurement by HPLC, causing a falsely high Hb A1c concentration when using the G11 apparatus with clinical implications possibly to follow.