doi:10.1016/j.gene.2003.12.035 
Copyright © 2004 Elsevier B.V. All rights reserved.
Micro-geographical differentiation in Northern Iberia revealed by Y-chromosomal DNA analysis
María Brion a, Bea Quintans a, Maite Zarrabeitia b, Anna Gonzalez-Neira a, Antonio Salas a, Victoria Lareu a, Chris Tyler-Smith c and Angel Carracedo a, 
, 
a Institute of Legal Medicine, University of Santiago de Compostela, San Francisco s/n., 15782, Santiago de Compostela, Spain
b Unit of Legal Medicine, University of Cantabria, 39011, Santander, Spain
c The Wellcome Trust Sanger Institute. Wellcome Trust Genome Campus. Hinxton, Cambs CB10 1SA, UK
Received 29 July 2003;
Revised 18 November 2003;
accepted 23 December 2003
Received by M. D'Urso
Available online 12 February 2004.
References and further reading may be available for this article. To view references and further reading you must
purchase this article.
Abstract
Y-chromosome diversity has been analyzed at a micro-geographical level, examining 10 binary polymorphisms and 7 short tandem repeats (STRs) in 443 samples belonging to 11 populations from two regions of Northern Spain, Galicia and Cantabria. Both regions, as a whole, cluster with other Iberian populations. However, some individual populations, particularly that from the Pas Valley in Cantabria, depart markedly from this general pattern, with higher genetic distances and reduced diversity. This unusual population is even more distinct than the Basques from their Iberian neighbors. Genetic drift in a small isolated population could explain this special behavior, and in addition to its anthropological interest, this finding has important forensic implications.
Author Keywords: Author Keywords: Binary polymorphisms; Microsatellites; Human diversity; Population substructure; Differentiation
AMOVA, analysis of molecular variance; EDTA, Ethylenediaminetetraacetic acid; HG, haplogroup; LR, likelihood ratio; MDS, multidimensional scaling; STR, short tandem repeats
Fig. 1. Distribution of Y-chromosomal haplogroups in Northern Iberia. (a) Rooted maximum parsimony tree of haplogroups. Marker names are indicated below the lines and lineage names are shown above the lines, but the length of each branch has no significance. Circles represent haplogroups, and their area is proportional to the frequency. (b) Map of Iberia indicating the region shown in (c–h). (c) Locations of population samples. (d–h) Frequencies of Y haplogroups in each population; (h) haplogroup frequency values are listed in the same order as the haplogroup name. Circles represent populations, and their area is proportional to sample size. Haplogroup color codes are as in (a).
Fig. 2. Principal component analysis of Y-chromosomal haplogroup frequencies. Iberian populations are shown as diamonds and are highlighted with a circle; other European or North African populations are shown as squares. The percentage of variance explained by each component is given on the axes.
Fig. 3. Multidimensional scaling plot of genetic distances. (a) Rho distances between populations based on the compound haplotypes. Stress VALUE=0.28. (b) ΦST distances based on the STR haplotype frequencies. Stress VALUE=0.07.
Fig. 4. Median-joining network of compound haplotypes. Circles represent haplotypes with an area proportional to frequency, and colors indicate the population of origin. Mutational differences are represented by lines, and the binary marker mutations are labeled.
Table 1. Published population data used in the principal component analysis
Table 2. Y-chromosomal diversity values
Table 3. Y-STR haplotypes found in five or more individuals
Table 4. Exact test of sample differentiation based on haplogroup and haplotype frequencies
Abstract
Purchase PDF (686 K)
E-mail Article
Add to my Quick Links
Cited By in Scopus (10)
Purchase PDF (142 K)
