RARE BETA-CHAIN HEMOGLOBIN-VARIANTS FOUND IN SWEDISH PATIENTS DURING HBA(1C) ANALYSIS

Here we report the occurrence of five different beta chain hemoglobin variants not previously described in Sweden. The variants were found during quantification of HbA1c using ion exchange high performance liquid chromatography (HPLC) or isoelectrofocusing. Samples were examined either at protein level by separation of globin chains on C-8 reversed phase HPLC, digestion with trypsin or lysylendopeptidase and separation of peptides by C18 reversed phase HPLC, or at DNA level by direct nucleotide sequencing of double-stranded DNA fragments amplified from exon 1+2 of the beta-globin gene. The variants were: Hb Raleigh [beta1(NA1)Val-->Ac-Ala], Hb J-Baltimore [beta16(A13)Gly-->Asp], Hb Tacoma [beta30(B12)Arg-->Ser], Hb K-Ibadan [beta46(CD5)Gly-->Glu], and Hb Fukuyama [beta77(EF1)His-->Tyr]. Hb Tacoma, Hb K-Ibadan, and Hb Fukuyama were slightly unstable in the isopropanol test, but no signs of hemolysis were found in the patients who all had normal hematological findings.