It seems possible that the Icelandic population has been selected for greater resistance to Seasonal Affective Disorder, e.g.:

http://www.ncbi.nlm.nih.gov/pubm...pubmed/ 11926077

which may have caused some differences between the Icelandic population and those further south.

Or else the presumed selection might have occured before the population went to Iceland if the migrants came from about the same latitude.

This is a very interesting result. An obvious candidate for selection is the black death sweeps in 1402-1404 and 1494-1495 that each wiped out 50% of the population, whereas England/Scotland were only esimated to have 20% mortality.

TLR1 and TLR10 (as well as TLR6) function as heterodimers with TLR2 to recognize bacterial lipoproteins. Yersinia pesis, the causitive agent of plague, exploits the TLR2/TLR6 heterodimer to supress the immune response and facilitate the infection whereas the TLR1/TLR6 dimer produces inflammation in response to Y. pestis that clears the infection (Depaolo et al. 2008 Cell Host and Microbe).

I wonder if these TLR1 and TLR10 alleles bias TLR2 signaling away from TLR6 and hence enhance immunity to Y. pestis infection?

Has anybody noticed ways that Icelanders tend to differ from Norwegians?

It's probably the kind of narcissism of small differences thing that members of the smaller population would notice but not members of the larger population.

steve, they look different. that's what people have said.

Interestingly, Region 9 would be where the pre-Viking Irish settlements in Iceland were, and coincidently this area seems the most divergent from the Norwegian/Scottish.

I would have thought the Irish would be a better proxy than the Scots for this study??