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Global Lactase Persistence Association Database GLAD

Lactase persistence is the ability of adult humans to digest the milk sugar lactose. LP is a dominant Mendelian trait that has been a subject of extensive genetic, medical, and evolutionary research.

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  • Global Lactase Persistence Association Database GLAD

This is an online database resource presenting LP phenotypic and genotypic allele frequency data: interpolated LP frequency maps are shown, focussing on the Old World. 

We encourage researchers to send us new LP phenotype / genotype data to Professor Dallas Swallow in an Excel format using headers identical to those in the tables linked below. 

Please make sure that the submitted phenotype data conform to the following criteria:

  • Random sampling
  • Known ethnicity and sampling location
  • Indigenous population (preferably, but please alert us and supply details, if not)
  • No hospital patients or individuals self reporting with gut problems

Latest Maps

Distribution of Lactase Persistence phenotype
 

Worldwide

worldwide map

Old World

pheno old world final

Dots represent test locations. Colours and colour key show LP frequency distribution represented by surface interpolation. Ingram,C.I, Montalva, N and Swallow, D.M. 2022 ‘Lactose Malabsorption’, in Advanced Dairy Chemistry, Volume 3: Lactose, Water, Salts and Minor Constituents McSweeney et al eds. ISBN 978-3-030-92584-0. See data links below.

Content is empty

13907g map


Dots represent collection locations. Colours and colour key show the allele frequency distribution represented by surface interpolation. Taken from Ingram,C.I, Montalva, N and Swallow, D.M. 2022 ‘Lactose Malabsorption’, in Advanced Dairy Chemistry, Volume 3: Lactose, Water, Salts and Minor Constituents McSweeney et al eds. ISBN 978-3-030-92584-0. See data links below.

Frequency of 13910*T (rs4988235)  

Frequency of 13910t

Dots represent collection locations. Colours and colour key show the allele frequency distribution represented by surface interpolation. Taken from Ingram,C.I, Montalva, N and Swallow, D.M. 2022 ‘Lactose Malabsorption’, in Advanced Dairy Chemistry, Volume 3: Lactose, Water, Salts and Minor Constituents McSweeney et al eds. ISBN 978-3-030-92584-0. See data links below.

Frequency of 13915*G (rs41380347)

Frequency of 13915G


Dots represent collection locations. Colours and colour key show the allele frequency distribution represented by surface interpolation. Taken from Ingram,C.I, Montalva, N and Swallow, D.M. 2022 ‘Lactose Malabsorption’, in Advanced Dairy Chemistry, Volume 3: Lactose, Water, Salts and Minor Constituents McSweeney et al eds. ISBN 978-3-030-92584-0. See data links below.

Frequency of 14009*G (rs869051967)  

Frequency of 14009G


Dots represent collection locations. Colours and colour key show the allele frequency distribution represented by surface interpolation. Taken from Ingram,C.I, Montalva, N and Swallow, D.M. 2022 ‘Lactose Malabsorption’, in Advanced Dairy Chemistry, Volume 3: Lactose, Water, Salts and Minor Constituents McSweeney et al eds. ISBN 978-3-030-92584-0. See data links below.

Frequency of 14010*C (rs145946881)

Frequency of 14010C


Dots represent collection locations. Colours and colour key show the allele frequency distribution represented by surface interpolation. Taken from Ingram,C.I, Montalva, N and Swallow, D.M. 2022 ‘Lactose Malabsorption’, in Advanced Dairy Chemistry, Volume 3: Lactose, Water, Salts and Minor Constituents McSweeney et al eds. ISBN 978-3-030-92584-0. See data links below.

Data

DatabaseVersionReference
LP Genotypes
Old World
2012 - DOWNLOADItan et al 2010
LP Phenotypes2012 - DOWNLOADItan et al 2010
LP Genotypes
Old World
2017 - DOWNLOADLiebert et al 2017
LP Genotypes
Old World
2020 - DOWNLOAD Ingram,C.I, Montalva, N and Swallow, D.M. 2022 ‘Lactose Malabsorption’, in Advanced Dairy Chemistry, Volume 3: Lactose, Water, Salts and Minor Constituents McSweeney et al eds. ISBN 978-3-030-92584-0

LP Phenotypes
with Americas

2020 - DOWNLOAD Ingram,C.I, Montalva, N and Swallow, D.M. 2022 ‘Lactose Malabsorption’, in Advanced Dairy Chemistry, Volume 3: Lactose, Water, Salts and Minor Constituents McSweeney et al eds. ISBN 978-3-030-92584-0

LP Ancient
Genotypes

2022 - 
DOWNLOAD
Evershed, R.P., Davey Smith, G., Roffet-Salque, M. et al. Dairying, diseases and the evolution of lactase persistence in Europe. Nature (2022). Data taken from v44.3 of the Allen Ancient DNA Resource (accessible at: https://reich.hms.harvard.edu/allen-ancient-dna-resource-aadr-downloadable-genotypes-present-day-and-ancient-dna-data). Single alleles (for read depth one) and maximum likelihood genotypes (for read depth above one) were obtained from pileups on BAM files for the set of individuals shown in Figure 2 of Evershed et al. As described in Evershed et al., rs4988235 genotypes for individuals PEN001_real2, Klei10.SG, and Iboussieres25-1 were manually set to the GG, as presence of the derived LP allele is believed to be due to post mortem damage.

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