title: Hemoglobin analyses in the Netherlands reveal more than 80 different variants including six novel ones.
abstract: More than 20,000 blood samples of individuals living in The Netherlands and suspected of hemolytic anemia or diabetes were analyzed by high resolution cation exchange high performance liquid chromatography (HPLC). Besides common disease-related hemoglobins (Hbs), rare variants were also detected. The variant Hbs were retrospectively analyzed by capillary zone electrophoresis (CZE) and by isoelectric focusing (IEF). For unambiguous identification, the globin genes were sequenced. Most of the 80 Hb variants detected by initial screening on HPLC were also separated by capillary electrophoresis (CE), but a few variants were only detectable with one of these methods. Some variants were unstable, had thalassemic properties or increased oxygen affinity, and some interfered with Hb A2 measurement, detection of sickle cell Hb or Hb A1c quantification. Two of the six novel variants, Hb Enschede (HBA2: c.308G  > A, p.Ser103Asn) and Hb Weesp (HBA1: c.301C > T, p.Leu101Phe), had no clinical consequences. In contrast, two others appeared clinically significant: Hb Ede (HBB: c.53A > T, p.Lys18Met) caused thalassemia and Hb Waterland (HBB: c.428C > T, pAla143Val) was related to mild polycytemia. Hb A2-Venlo (HBD: c.193G > A, p.Gly65Ser) and Hb A2-Rotterdam (HBD: c.38A > C, p.Asn13Thr) interfered with Hb A2 quantification. This survey shows that HPLC analysis followed by globin gene sequencing of rare variants is an effective method to reveal Hb variants.
authors.affiliation: Laboratory of Red Blood Cell Diagnostics, Sanquin Blood Supply Organization , Amsterdam , The Netherlands.
authors.forename: Rob
authors.initials: R
authors.lastname: van Zwieten
authors.forename: Martijn
authors.initials: M
authors.lastname: Veldthuis
authors.forename: Barend
authors.initials: B
authors.lastname: Delzenne
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Berghuis
authors.forename: Joke
authors.initials: J
authors.lastname: Groen
authors.forename: Fatima
authors.initials: F
authors.lastname: Ait Ichou
authors.forename: Els
authors.initials: E
authors.lastname: Clifford
authors.forename: Cornelis L
authors.initials: CL
authors.lastname: Harteveld
authors.forename: An K
authors.initials: AK
authors.lastname: Stroobants
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D019075:Electrophoresis, Capillary / Q000379:methods; D006453:Hemoglobinopathies / Q000175:diagnosis; D006454:Hemoglobins / Q000737:chemistry* / Q000235:genetics; D006455:Hemoglobins, Abnormal / Q000737:chemistry* / Q000235:genetics; D006801:Humans; D009154:Mutation; D009426:Netherlands; D013789:Thalassemia / Q000175:diagnosis / Q000235:genetics; D055542:alpha-Globins / Q000737:chemistry / Q000235:genetics; D055544:beta-Globins / Q000737:chemistry / Q000235:genetics
chemical_list: D006454:Hemoglobins; D006455:Hemoglobins, Abnormal; D055542:alpha-Globins; D055544:beta-Globins