Extensive geographical and social structure in the paternal lineages of Saudi

[Yaroslav]

Жаль, что-то не могу прорваться к полному тексту и к гаплотипам. Говорят, что они 27-локусные, формат Yfiler Plus.

Extensive geographical and social structure in the paternal lineages of Saudi Arabia revealed by analysis of 27 Y-STRs

Yahya M. Khubrani, Jon H. Wetton, Mark A. Jobling

Highlights

•Yfiler Plus (27-STR) haplotypes reported for 597 Saudi Arabian males.

•Discrimination capacity only 74.7% for 17 Yfiler STRs, but increases to 95.3% for Yfiler Plus.

•Five geographical subregions highly differentiated: low diversity in North and Centre, high diversity in West and East.

•Males sampled in UK (16%) highly differentiated from males sampled in Saudi Arabia, despite matching for sub-region of origin.

•Strong geographical and social structure for paternal lineages may affect forensic interpretation of Y-STR profiles in Saudi Arabia.

Abstract

Saudi Arabia’s indigenous population is organized into patrilineal descent groups, but to date, little has been done to characterize its population structure, in particular with respect to the male-specific region of the Y chromosome. We have used the 27-STR Yfiler® Plus kit to generate haplotypes in 597 unrelated Saudi males, classified into five geographical regions (North, South, Central, East and West). Overall, Yfiler® Plus provides a good discrimination capacity of 95.3%, but this is greatly reduced (74.7%) when considering the reduced Yfiler® set of 17 Y-STRs, justifying the use of the expanded set of markers in this population. Comparison of the five geographical divisions reveals striking differences, with low diversity and similar haplotype spectra in the Central and Northern regions, and high diversity and similar haplotype spectra in the East and West. These patterns likely reflect the geographical isolation of the desert heartland of the peninsula, and the proximity to the sea of the Eastern and Western areas, and consequent historical immigration. We predicted haplogroups from Y-STR haplotypes, testing the performance of prediction by using a large independent set of Saudi Arabian Y-STR + Y-SNP data. Prediction indicated predominance (71%) of haplogroup J1, which was significantly more common in Central, Northern and Southern groups than in East and West, and formed a star-like expansion cluster in a median-joining network with an estimated age of ∼2800 years. Most of our 597 participants were sampled within Saudi Arabia itself, but ∼16% were sampled in the UK. Despite matching these two groups by home sub-region, we observed significant differences in haplotype and predicted haplogroup constitutions overall, and for most sub-regions individually. This suggests social structure influencing the probability of leaving Saudi Arabia, correlated with different Y-chromosome compositions. The UK-recruited sample is an inappropriate proxy for Saudi Arabia generally, and caution is needed when considering expatriate groups as representative of country of origin. Our study shows the importance of geographical and social structuring that may affect the utility of forensic databases and the interpretation of Y-STR profiles.

Keywords:
Saudi Arabia, Y-STRs, Haplogroup, Haplotype, Population structure

[Arthwr]

Полный текст тут.