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I read through the submitted article here to find the link to the scientific journal article[1] that has just come out from this research group. The abstract tells the basic story:

"Performing genetic studies in multiple human populations can identify disease risk alleles that are common in one population but rare in others1, with the potential to illuminate pathophysiology, health disparities, and the population genetic origins of disease alleles. Here we analysed 9.2 million single nucleotide polymorphisms (SNPs) in each of 8,214 Mexicans and other Latin Americans: 3,848 with type 2 diabetes and 4,366 non-diabetic controls. In addition to replicating previous findings2, 3, 4, we identified a novel locus associated with type 2 diabetes at genome-wide significance spanning the solute carriers SLC16A11 and SLC16A13 (P = 3.9 × 10−13; odds ratio (OR) = 1.29). The association was stronger in younger, leaner people with type 2 diabetes, and replicated in independent samples (P = 1.1 × 10−4; OR = 1.20). The risk haplotype carries four amino acid substitutions, all in SLC16A11; it is present at ~50% frequency in Native American samples and ~10% in east Asian, but is rare in European and African samples. Analysis of an archaic genome sequence indicated that the risk haplotype introgressed into modern humans via admixture with Neanderthals. The SLC16A11 messenger RNA is expressed in liver, and V5-tagged SLC16A11 protein localizes to the endoplasmic reticulum. Expression of SLC16A11 in heterologous cells alters lipid metabolism, most notably causing an increase in intracellular triacylglycerol levels. Despite type 2 diabetes having been well studied by genome-wide association studies in other populations, analysis in Mexican and Latin American individuals identified SLC16A11 as a novel candidate gene for type 2 diabetes with a possible role in triacylglycerol metabolism."

The most novel and startling part of the factual claims in the abstract, and definitely the part that I am most dubious about, is "the risk haplotype introgressed into modern humans via admixture with Neanderthals." Well, maybe, but maybe not. There have been very few samples of ancient hominid DNA so far, so we are still not sure what range of variation was found among ancestors of today's Homo sapiens species to which we all belong.

[1] http://www.nature.com/nature/journal/vaop/ncurrent/full/natu...

Since the "Latino" category encompasses people of European, African, and Native American ancestry [1] [2], I was thinking the headline/article would be more informative if it stated which of these ancestral populations had the gene (assuming that question could be answered from the research methodology used).

Your comment answers my question; the gene occurs at highest frequency in Native American samples.

[1] http://en.wikipedia.org/wiki/Latino#Terminology

[2] http://en.wikipedia.org/wiki/Latin_Americans#Demographics

Very interesting! Thanks for sharing!
Does this imply that Neanderthals skedaddled to the Americas?

There was equal mention of Neanderthals and native Americans in the article but they seem to have avoided making the connection explicit.

No. It's disputed, but Neanderthals almost definitely died out before the human migration to North America.