Very low frequency of the lactase persistence allele in the Armenian population.

Primary lactose malabsorption is characterised by a down-regulation of lactase activity after weaning and inability to digest lactose in adulthood. It has been suggested that the historical introduction of dairying led to a positive selection for lactase persistence variants in a regulatory region upstream of the gene. Here, we genotyped 202 Armenian subjects for , a lactase persistence variant which is widespread in Europeans. The homozygous C/C genotype associated with primary hypolactasia, the heterozygous C/T and the homozygous T/T lactase persistence genotypes were found in 191 (94.6%), 11 (5.4%), and 0 (0.0%) samples, respectively. The frequency for the -13910*T allele was 2.7%. The observed allele frequency of 2.7% for - is even lower than previously reported and supports current phenotypic data about lactose malabsorption in Armenia.