Saudi Arabian Y-Chromosome diversity and its relationship with nearby regions

Khaled K Abu-Amero,Peter A Underhill,Ali Hellani,Jose M Larruga,Ana M González,Vicente M Cabrera

doi:10.1186/1471-2156-10-59

Abstract

BackgroundHuman origins and migration models proposing the Horn of Africa as a prehistoric exit route to Asia have stimulated molecular genetic studies in the region using uniparental loci. However, from a Y-chromosome perspective, Saudi Arabia, the largest country of the region, has not yet been surveyed. To address this gap, a sample of 157 Saudi males was analyzed at high resolution using 67 Y-chromosome binary markers. In addition, haplotypic diversity for its most prominent J1-M267 lineage was estimated using a set of 17 Y-specific STR loci.ResultsSaudi Arabia differentiates from other Arabian Peninsula countries by a higher presence of J2-M172 lineages. It is significantly different from Yemen mainly due to a comparative reduction of sub-Saharan Africa E1-M123 and Levantine J1-M267 male lineages. Around 14% of the Saudi Arabia Y-chromosome pool is typical of African biogeographic ancestry, 17% arrived to the area from the East across Iran, while the remainder 69% could be considered of direct or indirect Levantine ascription. Interestingly, basal E-M96* (n = 2) and J-M304* (n = 3) lineages have been detected, for the first time, in the Arabian Peninsula. Coalescence time for the most prominent J1-M267 haplogroup in Saudi Arabia (11.6 ± 1.9 ky) is similar to that obtained previously for Yemen (11.3 ± 2) but significantly older that those estimated for Qatar (7.3 ± 1.8) and UAE (6.8 ± 1.5).ConclusionThe Y-chromosome genetic structure of the Arabian Peninsula seems to be mainly modulated by geography. The data confirm that this area has mainly been a recipient of gene flow from its African and Asian surrounding areas, probably mainly since the last Glacial maximum onwards. Although rare deep rooting lineages for Y-chromosome haplogroups E and J have been detected, the presence of more basal clades supportive of the southern exit route of modern humans to Eurasian, were not found.

Highlights

Human origins and migration models proposing the Horn of Africa as a prehistoric exit route to Asia have stimulated molecular genetic studies in the region using uniparental loci
The arid Arabian Peninsula can be viewed as a geographic cul de sac and passive recipient of Near East cultural and demic expansions since the Bronze Age
Y-SNP analysis Only 27 of the 67 binary markers analyzed were informative in defining the haplogroup census of the Saudi Arabian sample (Table 1)

Summary

Introduction

Human origins and migration models proposing the Horn of Africa as a prehistoric exit route to Asia have stimulated molecular genetic studies in the region using uniparental loci. From a Y-chromosome perspective, Saudi Arabia, the largest country of the region, has not yet been surveyed. To address this gap, a sample of 157 Saudi males was analyzed at high resolution using 67 Y-chromosome binary markers. More recent field work has sampled new Palaeolithic sites in Oman, under covering lithic assemblages with typological affinities to industries in the Levant, India and the Horn of Africa, suggesting there were a series of huntergathers range expansions into southern Arabia from all three refugia over the last quarter of a million years [6]. The passage of these hominids to Arabia could be either through an overland route or across a waterway

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