CEU HapMap sample

The CEU HapMap sample consists of "Utah residents with ancestry from northern and western Europe". The paper Geographical Affinities of the HapMap Samples contains this bit of retardation:

The lack of detailed similarity between the genome-wide autosomal genotypes of the CHB and CEU samples and the HGDP-CEPH panel could reflect the combination of high discriminatory power from such a large number of SNPs and the small number of comparison populations. In a more detailed comparison of the CEU with 2,457 individuals from 23 European populations, individual's SNP genotypes were clustered using principal component analysis [26]. Individuals from each European population generally clustered together and although the populations formed overlapping clusters, the broad North, South, East and West geographical areas of Europe were readily separated. In this analysis, the CEU were most similar to samples from the Netherlands and the UK, in agreement with the Y-chromosomal data, but in contrast were quite distinct from Spanish and Portuguese samples, which were not significantly different at the Y-chromosomal level (c.f. Figure 3B). We compared the number of samples that showed different or not different Y-chromosomal distances from the CEU in Central, Northern, Southern, Eastern and Western Europe with, in each case, the rest of Europe, using a Fisher exact test and found a striking enrichment of similar samples in Western Europe (p<0.000001) but in no other region. Some differences between a single locus and the combination of a large number of loci is unsurprising, but may also reflect the limited number of Y-STRs available for the detailed European comparison and the similarities in Y-chromosomal haplotypes throughout much of Western Europe, where haplogroup R1b predominates, being common in both Britain and Iberia [27], [28], for example. Together, these results show that the CEU, in contrast to the HapMap recommended descriptor ‘Utah residents with ancestry from northern and western Europe’ (http://www.hapmap.org/citinghapmap.html) are not appropriately described as having Northern European ancestry; Western or North-western Europe ancestry would be more accurate.

Apparently, this is what happens when Chinese lead authors try to write about Europe. Hint: Northwestern Europe is the intersection of Northern Europe and Western Europe. Every analysis I've ever seen supports the NW European affinities of the CEU sample (also see "Geographical structure and differential natural selection amongst North European populations"), including analyses in this paper. Low-resolution Y-STR matches throughout western Europe are expected and are absolutely irrelevant.