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Angela
25-08-16, 22:58
See:
"Inferring the genetic history of lactase persistence along the Italian peninsula from a large genomic interval surrounding the LCT gene. (http://www.pubfacts.com/detail/26175013/Inferring-the-genetic-history-of-lactase-persistence-along-the-Italian-peninsula-from-a-large-genomi)"

Sara De Fanti (http://www.pubfacts.com/author/Sara+De%20Fanti), Marco Sazzini (http://www.pubfacts.com/author/Marco+Sazzini), Cristina Giuliani (http://www.pubfacts.com/author/Cristina+Giuliani), Federica Frazzoni (http://www.pubfacts.com/author/Federica+Frazzoni), Stefania Sarno (http://www.pubfacts.com/author/Stefania+Sarno), Alessio Boattini (http://www.pubfacts.com/author/Alessio+Boattini), Elena Marasco (http://www.pubfacts.com/author/Elena+Marasco), Vilma Mantovani (http://www.pubfacts.com/author/Vilma+Mantovani), Claudio Franceschi (http://www.pubfacts.com/author/Claudio+Franceschi), Pedro Moral (http://www.pubfacts.com/author/Pedro+Moral), Paolo Garagnani (http://www.pubfacts.com/author/Paolo+Garagnani), Donata Luiselli (http://www.pubfacts.com/author/Donata+Luiselli)

"Although genetic variants related to lactase persistence in European populations were supposed to have firstly undergone positive selection in farmers from the Balkans and Central Europe, demographic and evolutionary dynamics that subsequently shaped the distribution of this adaptive trait across the continent have still to be elucidated. To deepen the knowledge about potential routes of diffusion of lactase persistence to Western Europe we investigated variation at a large genomic region surrounding the LCT gene along the Italian peninsula, a geographical area that played a key role in population movements responsible for Neolithic diffusion across Europe.

By genotyping 40 highly selected SNPs in more than 400 Italian individuals we described gradients of nucleotide and haplotype variation potentially related to lactase persistence and compared them with those observed in several European and Mediterranean human groups.


Multiple migratory events responsible for earlier introduction of the examined alleles in Italy than in Northern European regions could be invoked. Different demic processes occurred along the western and eastern sides of the peninsula were also inferred via linkage disequilibrium and population structure analyses.

The appreciable genetic continuum observed between people from Northern or Central-Western Italy and Central European populations suggested a local arrival of lactase persistence-related variants mainly via overland routes. On the contrary, diversity of Central-Eastern and Southern Italian groups entailed also gene flow from South-Eastern Mediterranean regions, in accordance to the earlier entrance of the Neolithic in Southern Italy via maritime population movements along the Mediterranean coastlines."

Don't get too excited, some of you...the rest is behind a pay wall. If anybody has access, can you get us a few more specifics? A map by region would be nice.

http://onlinelibrary.wiley.com/doi/10.1002/ajpa.22814/abstract?systemMessage=Wiley+Online+Library+will+b e+unavailable+on+Saturday+3rd+September+2016+at+08 .30+BST%2F+03%3A30+EDT%2F+15%3A30+SGT+for+5+hours+ and+Sunday+4th+September+at+10%3A00+BST%2F+05%3A00 +EST%2F+17%3A00+SGT+for+1+hour++for+essential+main tenance.+Apologies+for+the+inconvenience

Without the text I'm not sure what I'm looking at here from the Supplementary Info, other than that there are a lot of snps involved, and perhaps different ones came at different time to different areas?
http://onlinelibrary.wiley.com/store/10.1002/ajpa.22814/asset/supinfo/ajpa22814-sup-0003-suppinfofigS3.pdf?v=1&6287d4ef

Moi-même
26-08-16, 01:31
Sound promising, I hope we will get more details.

Sile
26-08-16, 19:57
THe maps are interesting

Abstract
Although genetic variants related to lactase persistence in European populations were supposed to have firstly undergone positive selection in farmers from the Balkans and Central Europe, demographic and evolutionary dynamics that subsequently shaped the distribution of this adaptive trait across the continent have still to be elucidated. To deepen the knowledge about potential routes of diffusion of lactase persistence to Western Europe we investigated variation at a large genomic region surrounding the LCT gene along the Italian peninsula, a geographical area that played a key role in population movements responsible for Neolithic diffusion across Europe. By genotyping 40 highly selected SNPs in more than 400 Italian individuals we described gradients of nucleotide and haplotype variation potentially related to lactase persistence and compared them with those observed in several European and Mediterranean human groups. Multiple migratory events responsible for earlier introduction of the examined alleles in Italy than in Northern European regions could be invoked. Different demic processes occurred along the western and eastern sides of the peninsula were also inferred via linkage disequilibrium and population structure analyses. The appreciable genetic continuum observed between people from Northern or Central-Western Italy and Central European populations suggested a local arrival of lactase persistence-related variants mainly via overland routes. On the contrary, diversity of Central-Eastern and Southern Italian groups entailed also gene flow from South-Eastern Mediterranean regions, in accordance to the earlier entrance of the Neolithic in Southern Italy via maritime population movements along the Mediterranean coastlines.

https://www.researchgate.net/publication/280103565_Inferring_the_Genetic_History_of_Lactase _Persistence_Along_the_Italian_Peninsula_from_a_La rge_Genomic_Interval_Surrounding_the_LCT_Gene

Angela
26-08-16, 20:34
Maybe I'm being dense today, but I still don't get it. Has anybody figured out precisely what the maps are showing?

Or this, for that matter. Are these all the alleles that affect it?

https://www.researchgate.net/figure/280103565_fig1_Figure-2-Median-joining-network-of-the-inferred-haplotypes-Haplotypes-H_2-H_9-H_17