title: Lactase non-persistence and milk consumption in Estonia.
abstract: OBJECTIVE
  To define the frequency of the C/T-13910 variant associated with lactase persistence/non-persistence trait and to analyze the milk consumption of lactase non-persistent subjects in Estonia.
  
  
  METHODS
  We genotyped 355 Estonians by polymerase chain reaction and direct sequencing. Milk consumption was analyzed by a questionnaire, specially developed to analyze milk consumption and abdominal complaints.
  
  
  RESULTS
  The frequency of the genotype of the C/C-13910 (lactase non-persistence) was found to be 24.8% in native Estonians. No other single nucleotide polymorphisms covering the region of 400 bp adjacent to the C/T-13910 variant were found. Lactase non-persistence subjects were found to consume less milk than lactase persistence subjects.
  
  
  CONCLUSIONS
  The frequency of lactase non-persistence defined by the C/C-13910 genotype confirms the results of the previous studies based on indirect methods of determining hypolactasia. Milk consumption of lactase non-persistence subjects is consistent with previously reported figures of adult-type hypolactasia in Estonia. However, lactase non-persistence does not prevent the intake of milk in many adults.
authors.affiliation: Department of Internal Medicine, University of Tartu, Estonia. margus.lember@kliinikum.ee
authors.forename: Margus
authors.initials: M
authors.lastname: Lember
authors.forename: Suvi
authors.initials: S
authors.lastname: Torniainen
authors.forename: Mart
authors.initials: M
authors.lastname: Kull
authors.forename: Riina
authors.initials: R
authors.lastname: Kallikorm
authors.forename: Peeter
authors.initials: P
authors.lastname: Saadla
authors.forename: Tarvo
authors.initials: T
authors.lastname: Rajasalu
authors.forename: Hanna
authors.initials: H
authors.lastname: Komu
authors.forename: Irma
authors.initials: I
authors.lastname: Järvelä
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D004247:DNA / Q000097:blood / Q000235:genetics; D053938:DNA Fragmentation; D017931:DNA Primers; D004957:Estonia / Q000453:epidemiology; D005260:Female; D005838:Genotype; D006801:Humans; D043322:Lactase / Q000235:genetics*; D007787:Lactose Intolerance / Q000453:epidemiology / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D008892:Milk / Q000201:enzymology*; D016133:Polymerase Chain Reaction
chemical_list: D017931:DNA Primers; D004247:DNA; D043322:Lactase