Independent introduction of two lactase-persistence alleles into human populations reflects different history of adaptation to milk culture.

@article{Enattah2008IndependentIO,
  title={Independent introduction of two lactase-persistence alleles into human populations reflects different history of adaptation to milk culture.},
  author={Nabil Sabri Enattah and Tine G. K. Jensen and Mette Nielsen and Rikke Lewinski and Mikko Kuokkanen and Heli Rasinpera and Hatem El-Shanti and Jeong Kee Seo and Michael Alifrangis and Insaf F. Khalil and Abdrazak Natah and Ahmed A.A. Ali and Sirajedin S. Natah and David Comas and Syed Qasim Mehdi and Leif C. Groop and Else Marie Vestergaard and Faiqa Imtiaz and Mohamed S. Rashed and Brian F. Meyer and Jesper Thorvald Troelsen and Leena Peltonen},
  journal={American journal of human genetics},
  year={2008},
  volume={82 1},
  pages={
          57-72
        }
}

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References

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TLDR
A genotype-phenotype association study in Tanzanians, Kenyans and Sudanese and identified three SNPs that are associated with lactase persistence and that have derived alleles that significantly enhance transcription from the LCT promoter in vitro, providing a marked example of convergent evolution due to strong selective pressure resulting from shared cultural traits.
A novel polymorphism associated with lactose tolerance in Africa: multiple causes for lactase persistence?
TLDR
A cohort study of lactose digester and non-digester Sudanese volunteers shows there is no association of -13910*T or the A haplotype with lactase persistence, and reveals the complexity of this phenotypic polymorphism and highlights the limitations of C-13910T as a diagnostic test for lact enzyme persistence status, at least for people with non-European ancestry.
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This study shows that a limited number of microsatellite loci may provide sufficient resolution to reconstruct key aspects of the evolutionary history of lactase persistence, providing an alternative to approaches based on large numbers of SNPs.
An upstream polymorphism associated with lactase persistence has increased enhancer activity.
TLDR
The discovery of a functional difference between the 2 alleles at position -13910 supports the notion that the molecular difference between lactase persistence and nonpersistence is caused by the mutation at position-13910.
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TLDR
A DNA variant, C/T−13910, completely associates with biochemically verified lactase non-persistence in Finnish families and a sample set of 236 individuals from four different populations, indicating that it is very old.
T-13910 DNA variant associated with lactase persistence interacts with Oct-1 and stimulates lactase promoter activity in vitro.
TLDR
The data suggest that the binding of Oct-1 to the T-13,910 variant directs increased lactase promoter activity and this might provide an explanation for the lactase persistence phenotype in the human population.
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TLDR
It is estimated that strong selection occurred within the past 5,000-10,000 years, consistent with an advantage to lactase persistence in the setting of dairy farming; the signals of selection the authors observe are among the strongest yet seen for any gene in the genome.
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TLDR
The DNA region of the C/T_(13910) lactase persistence/non-persistence variant functions in vitro as a cis element capable of enhancing differential transcriptional activation of the lactase promoter.
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The hypothesis that malaria has had a major impact on humans only since the introduction of agriculture within the past 10,000 years is supported and the locus of “A−” and ”Med” mutations provides a striking example of the signature of selection on the human genome.
A novel proximal -13914G>A base replacement in the vicinity of the common-13910T/C lactase gene variation results in an atypical LightCycler melting curve in testing with the MutaREAL Lactase test.
TLDR
A defined DNA transition (−13910T/C) proximal to the LCT gene in intron 13 of the adjacent minichromosome maintenance type 6 gene ( MCM6 ), which is associated with verified lactase nonpersistence and reduced bone mineral density predisposing for bone fractures is identified.
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