The scale and nature of Viking settlement in Ireland from Y-chromosome admixture analysis

Abstract

The Vikings (or Norse) played a prominent role in Irish history but, despite this, their genetic legacy in Ireland, which may provide insights into the nature and scale of their immigration, is largely unexplored. Irish surnames, some of which are thought to have Norse roots, are paternally inherited in a similar manner to Y-chromosomes. The correspondence of Scandinavian patrilineal ancestry in a cohort of Irish men bearing surnames of putative Norse origin was examined using both slow mutating unique event polymorphisms and relatively rapidly changing short tandem repeat Y-chromosome markers. Irish and Scandinavian admixture proportions were explored for both systems using six different admixture estimators, allowing a parallel investigation of the impact of method and marker type in Y-chromosome admixture analysis. Admixture proportion estimates in the putative Norse surname group were highly consistent and detected little trace of Scandinavian ancestry. In addition, there is scant evidence of Scandinavian Y-chromosome introgression in a general Irish population sample. Although conclusions are largely dependent on the accurate identification of Norse surnames, the findings are consistent with a relatively small number of Norse settlers (and descendents) migrating to Ireland during the Viking period (ca. AD 800 -1200) suggesting that Norse colonial settlements might have been largely composed of indigenous Irish. This observation adds to previous genetic studies that point to a flexible Viking settlement approach across North Atlantic Europe.

Metamizole (dipyrone)-induced agranulocytosis: Does the risk vary according to ethnicity?

“…The prevalence of various HLA alleles varies widely in different populations. Although the British, Irish and Scandinavian populations are now culturally distinct and geographically separate from each other, there are historical reasons dating back to centuries to suggest that some of their key genetic features overlap . The inevitable question is whether the three populations also share parts of their HLA allelic profile and, therefore, the high risk of dipyrone‐induced agranulocytosis; one study has already reported a high incidence of this complication in Sweden at one case per 1439 prescriptions .…”

“…Although the British, Irish and Scandinavian populations are now culturally distinct and geographically separate from each other, there are historical reasons dating back to centuries to suggest that some of their key genetic features overlap. [52][53][54][55][56] The inevitable question is whether the three populations also share parts of their HLA allelic profile and, therefore, the high risk of dipyrone-induced agranulocytosis; one study has already reported a high incidence of this complication in Sweden at one case per 1439 prescriptions. 3 Provided specific HLA allele(s) can be identified to be associated, with sufficient specificity and sensitivity, with dipyrone-induced agranulocytosis, it may be worth investigating whether the prevalence of these HLA alleles is higher in the…”

Biological diversity in an Islamic archaeological population: A radiogenic strontium isotope and craniometric analysis of affinity in Ottoman Romania

“…Admixture results from the homogenizing effects of gene flow between populations that were previously reproductively isolated, as is often the outcome from mass migratory or colonization processes (Martínez-Abadías et al, 2006). Previous DNA studies have successfully reconstructed the biological impacts of global migrations, identifying historical admixture in genetic data (Hellenthal et al, 2014;McEvoy, Brady, Moore, & Bradley, 2006;Patterson et al, 2012;Zalloua et al, 2008). Likewise, morphological analyses have detected admixture in craniofacial forms, as phenotypic indicators of admixture are seen in the intermediary morphological forms between parent populations (Martínez-Abadías et al, 2006;Ross, Slice, Ubelaker, & Falsetti, 2004).…”

Finding Vikings with Isotope Analysis: The View from Wet and Windy Islands

“…Genetically, the modern populations of northern and western Scotland have significant Scandinavian ancestry in both the female and male lines (Goodacre et al 2005). Significant Scandinavian ancestry has not yet been discovered in Ireland (e.g., McEvoy et al 2006). However, elsewhere around the Irish Sea elegant studies linking Y-chromosomes and surnames of the modern population suggest enduring male Scandinavian genetic legacy in the Wirral in northwest England-a region potentially colonized from Dublin in the 10 th century (Bowden et al 2007).…”