I was race-classified once in a bicycle shop. "Try on some helmets" she said "and we'll find out whether you're really French or Italian".

I'm feeling totally cowed by Razib's command to read the article first - I'm unable to stay awake while reading anything written by scientists for other scientists. So can anyone non-Razib who's looked at the article pass along a couple-of-sentence, plain-English summary of it? Anything good in it, like something that might help explain the diffs between the cuisines or musics of Northern and Southern Europe? I think tastes and pleasures (and thus art and culture styles) have to based in genetics, at least to some extent. God knows I'm always hoping definitive proof will come along.

If you take into account the information given for both uniparental markers, y chromosome and mtDNA, you will see that despite the majoritarian R1b mutation in spaniards or italians, the mtDNA of southern europeans is not similar to the northerners( north atlantic europe).

http://www.journals.uchicago.edu...4/ 41464.web.pdf

I have a terrible curiosity about how some fringe populations like Basques or Galicians cluster in this north-south axis.
I think we the Galicians, based in mtDNA and autosomal SNPs, cluster together with western europeans and not with the mediterranean populations( italians, spaniards, greeks). But we are predominantly northern europeans? Maybe 50% predominantly northern and 50% southern?
Maybe, this work ilustrates some cultural and historical trends in Europe, that comes from prehistorical and historical population movements : neolithic waves, indoeuropean languages, celts, gemanic invaders...

I wonder what the results would be for the Northern Balkans, places like Croatia, but also South Central Europe, like Austria, Slovakia and Slovenia??

here's the synopsis ... written by the authors:

Two unrelated persons in the human population have hundreds of thousands of base pair
differences between them in DNA sequence. Previous studies have shown that a small
proportion of these sequence differences correlate with a person’s continental ancestry –
broadly Asia, Africa Oceana, America or continental Europe. In the current study, DNA
differences within a particular continental group, Europe, were examined. Overall, the
analysis of sequence variation allowed us to distinguish individuals with northern
European ancestry (Swedish, English, Irish, German, Ukraine) from individuals with
southern European ancestry (Italy, Spain, Portugal, and Greece). Interestingly,
Ashkenazi Jewish individuals tend to group together with individuals from southern
European countries. This study is important because it provides a method of taking into
account these differences when searching for genetic variations that are associated with
particular human traits, such as disease susceptibility, response to drug treatment or side
effects from therapy. Specifically, these methods may allow scientists to uncover
disease-associated genetic variations that might be hidden without considering
differences related to European ancestry.

michael,

always jump to the discussion after reading the introduction.

Notice that only 23/43 individuals from northern Spain and 5/19 from southern Spain had a "northern European" component greater than 10%. The Irish on the other hand were almost purely northern (mean contribution = 97%). In the factor analyses, too, there is no overlap between Irish and Spaniards.

So I hope everyone now realizes that recent highly-publicized theories about a Spanish-Irish consanguinity are just a lot of hooey, relying too heavily on too little data (Y chromosome haplotypes). The picture painted by a genome-wide set of markers is completely different, as this study is only the latest to show.

I think, going back to the Cavalli-Sforza principal component analysis date of a few years ago, and now including this fresh data, they should have really named their clusters, NorthWestern and SouthEastern, as with the exception of the Finns, these areas best represent the extremes in Europe.

emile, i was thinking the same thing. the only issue i would have though is that the authors seem to be focusing on the north-south factor more than the west-east factor, perhaps because of the data sample they had (fewer easterners).

whoa whoa... not my synopsis... plos papers include a synopsis... it actually was written by the authors

update: i've deleted the comments with the very nice but misdirected praise so that no one else gets the wrong idea.

reading papers: if you don't know the science, read the intro and then the discussion... if you know the science, just look at the figures

Scientists, sheesh, they've got their own way of going about things ...

Consider these frequencies of a SNP in European populations:

NorthEastern=45
NorthWestern=30
SouthWestern=25
SouthEastern=10
_______________________________________________
Northerners Average= 37.5
Southerners Average= 17.5
-------------------------
North-South Gradient = 20

Westerners Average=27.5
Easterns Average= 27.5
---------------------------
West-East Gradient = 0
__________________________________________
N-S Gradient is greater than W-E Gradient
__________________________________________
But, the southwestern population is still closer to the northwestern population. There is a clear North-South Gradient but if you take into account the differences in frequencies, the SW is more similar to NW than SE, despite the gradient.
Maybe, thousands of SNPs present this pattern in Europe. In fact, the population of europe came from northern asia. There is no contradiction with previous works.
What do you think about this? is there any error in this reasoning?

When comparing with previous information, this gives yet further evidence that Y-chromosome distributions are strongly prone to replacement.

Anyone have data on probable selfish genes in the y-chromosome? Or maybe the traits it affects just have a lot of influence on fitness.

So I hope everyone now realizes that recent highly-publicized theories about a Spanish-Irish consanguinity are just a lot of hooey

I think the theories really concern a Basque-Irish connection rather than a Spanish-Irish one.

Nah, that Spanish/Irish thing was doing the rounds more than 50 years ago, it's a perennial bit of mythology. My mother still insists it was because of all the sailors from the Spanish Armada wrecked on the coast of Ireland. They have to try to explain the Black Irish somehow.