The T allele of a single-nucleotide polymorphism 13.9 kb upstream of the lactase gene (LCT) (C-13.9kbT) does not predict or cause the lactase-persistence phenotype in Africans.

@article{Mulcare2004TheTA,
  title={The T allele of a single-nucleotide polymorphism 13.9 kb upstream of the lactase gene (LCT) (C-13.9kbT) does not predict or cause the lactase-persistence phenotype in Africans.},
  author={Charlotte A. Mulcare and Michael E. Weale and Abigail L. Jones and Bruce Connell and David Zeitlyn and Ayele Tarekegn and Dallas M. Swallow and Neil Bradman and Mark George Thomas},
  journal={American journal of human genetics},
  year={2004},
  volume={74 6},
  pages={
          1102-10
        }
}
The ability to digest the milk sugar lactose as an adult (lactase persistence) is a variable genetic trait in human populations. The lactase-persistence phenotype is found at low frequencies in the majority of populations in sub-Saharan Africa that have been tested, but, in some populations, particularly pastoral groups, it is significantly more frequent. Recently, a CT polymorphism located 13.9 kb upstream of exon 1 of the lactase gene (LCT) was shown in a Finnish population to be closely… 

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