title: A novel exonuclease (TaqMan) assay for rapid haptoglobin genotyping.
abstract: BACKGROUND
  Haptoglobin is an acute-phase binding protein that scavenges free hemoglobin. The human haptoglobin gene (HP) is polymorphic with two main alleles, haptoglobin allele 1 (Hp1) and haptoglobin allele 2 (Hp2). The smaller Hp1 allele features no duplication and consists of four exons, whereas the larger Hp2 allele, containing a 1.7 kb duplication, consists of six exons, with the fifth and sixth being highly homologous to exons 3 and 4 of Hp1.
  
  
  METHODS
  We designed an exonuclease (TaqMan) assay targeting single nucleotide differences between the homologous regions of Hp1 and Hp2. The assay contained one probe specifically binding to a site in intron 4 of Hp2, and another probe binding equally to intron 4 of Hp1 and intron 6 of Hp2.
  
  
  RESULTS
  Measurement of post-PCR fluorescence allowed unambiguous discrimination of HP genotypes. Comparison with genotypes obtained by a method based upon allele-specific primers yielded fully corresponding results.
  
  
  CONCLUSIONS
  The new HP genotyping method is fast, reliable, does not require real-time instruments and may be especially useful for high-throughput genotyping.
authors.forename: Wilfried
authors.initials: W
authors.lastname: Renner
authors.forename: Renate
authors.initials: R
authors.lastname: Jahrbacher
authors.forename: Ernestine
authors.initials: E
authors.lastname: Marx-Neuhold
authors.forename: Simone
authors.initials: S
authors.lastname: Tischler
authors.forename: Barbara
authors.initials: B
authors.lastname: Zulus
mesh_terms: D000483:Alleles; D005092:Exonucleases / Q000378:metabolism*; D005453:Fluorescence; D005838:Genotype; D006242:Haptoglobins / Q000235:genetics*; D006801:Humans; D016133:Polymerase Chain Reaction
chemical_list: D006242:Haptoglobins; D005092:Exonucleases