title: Lactase persistence genotyping: rapid detection of seven sequence variants in a single tube with melting curve analyses.
abstract: BACKGROUND
  Lactase persistence is an inherited autosomal dominant trait that confers the ability to digest lactose after weaning. Lactose persistence is caused by single nucleotide variants in a regulatory element for the lactase gene (LCT). In Europeans, lactase persistence is associated with the nucleotide variant LCT -13910C>T. Ethnic groups from Africa and the Arabian Peninsula have other lactase persistence variants in close proximity to the -13910C>T variant. Current hybridisation probe analysis methods have been limited by the inability to detect all the known nucleotide variants. The aim of this study was to devise a method based on hybridisation probes and melting curve analysis for rapidly detecting LCT variants.
  
  
  METHODS
  We designed hybridisation probes for producing melting curve profiles that could identify seven LCT nucleotide variants: -13907C>G, -13910C>T, -13913T>C, -13914G>A, -13915T>G, -14009T>G, and -14010G>C. To validate the assay, we generated plasmid standards of all the alleles and mixed them to create artificial heterozygote samples.
  
  
  RESULTS
  All genotypes could be detected in a single tube assay. Rare genotypes were confirmed in a second assay with probes that had different complementary sequences.
  
  
  CONCLUSIONS
  This assay can be used for rapidly genotyping lactase persistence in multi-ethnic populations.
authors.forename: Harald
authors.initials: H
authors.lastname: Strand
authors.forename: Liv Karin
authors.initials: LK
authors.lastname: Sørensen
authors.forename: Ole Christian
authors.initials: OC
authors.lastname: Ingebretsen
mesh_terms: D001483:Base Sequence; D017931:DNA Primers / Q000235:genetics; D015342:DNA Probes / Q000235:genetics; D005838:Genotype; D006801:Humans; D043322:Lactase / Q000235:genetics*; D007787:Lactose Intolerance / Q000175:diagnosis / Q000201:enzymology / Q000235:genetics; D015336:Molecular Probe Techniques; D008969:Molecular Sequence Data; D009691:Nucleic Acid Denaturation; D009693:Nucleic Acid Hybridization; D020641:Polymorphism, Single Nucleotide; D060888:Real-Time Polymerase Chain Reaction; D050436:Regulatory Elements, Transcriptional
chemical_list: D017931:DNA Primers; D015342:DNA Probes; D043322:Lactase