Multiplexing with three-primer PCR for rapid and economical microsatellite validation.

The next generation sequencing revolution has enabled rapid discovery of genetic markers, however, development of fully functioning new markers still requires a long and costly process of marker validation. This study reports a rapid and economical approach for the validation and deployment of polymorphic microsatellite markers obtained from a 454 pyrosequencing library of Atlantic cod, Gadus morhua, Linnaeus 1758. Primers were designed from raw reads to amplify specific amplicon size ranges, allowing effective PCR multiplexing. Multiplexing was combined with a three-primer PCR approach using four universal tails to label amplicons with separate fluorochromes. A total of 192 primer pairs were tested, resulting in 73 polymorphic markers. Of these, 55 loci were combined in six multiplex panels each containing between six and eleven markers. Variability of the loci was assessed on G. morhua from the Celtic Sea (n 46) and the Scotian Shelf (n 46), two locations that have shown genetic differentiation in previous studies. Multilocus FST between the two samples was estimated at 0.067 (P 0.001). After three loci potentially under selection were excluded, the global FST was estimated at 0.043 (P 0.001). Our technique combines three- primer and multiplex PCR techniques, allowing simultaneous screening and validation of relatively large numbers of microsatellite loci.

Dublin 1916: theatre of revolt

At Easter 1916, Dublin city centre was one of a series of sites throughout Ireland where a rebellion was staged against British rule. It was a strategic failure, swiftly crushed by superior British forces. The event, however, subsequently took a central role in the mythology of modern Ireland.

The first visual representations were of the conflict’s aftermath: photographic journeys through landscapes of ruin. From the distance of the camera, we see none of the pockmarks of shell bursts, nor the etchings of machine guns. Instead, traces of life in the city seem to have been swept aside by an unseen hand: the passing of millennia or a violent action of nature. Architecture alone has witnessed and recorded its presence. Amongst the fragments, the shell of the General Post Office (G.P.O.) in Sackville Street is one of the few buildings still wholly recognizable. The remnants of its classical form, portico and pediment, columns and entablature seem to transcend its prosaic modern functions and allude to something more ancient. The bewilderment of city’s inhabitants is also recorded. Dubliners have become inquisitive tourists in streets which hitherto were the locus of everyday life. They wander around aimlessly in a landscape as alien and picturesque as Pompeii. This shift in perception was captured by the Irish poet W.B. Yeats who hinted that Dublin, purged of modern commercialism had transcended its petty inadequacies to revive a slumbering heroic past.

‘I have met them at the close of day
Coming with vivid faces
From counter or desk among grey
Eighteenth-century houses [.]’
All is changed, changed utterly:
A terrible beauty is born.’

His comments were prescient. Initially unpopular, the republican leaders, executed by the British, slowly became recast as heroic martyrs. Similarly, the spaces where their heroism was forged became venerated. The G.P.O. and Sackville Street, however, already had a republican history. It was originally conceived in the eighteenth century as part of a series of magnificent urban spaces to provide an arena of spectacle and self-celebration for the colonial Anglo-Irish and their vision of a Protestant republic. O’Connell/Sackville Street became the temporal, geographical and mythical hinge upon which two different versions of Irish republicanism waxed and waned. Its recasting after independence as a space of Catholic Nationalism bore testimony to its consistency in providing a backdrop for the production of ritual and myth. In the 1920s and 30s, as the nascent country, beset with economic stagnation and political tensions, turned to spectacle as a salve for it social problems, O’Connell Street and the G.P.O. provided its most sacred sites. Within the introduction of new myths, however, individual as well as national identities were created and consolidated. The emerging identity of modern Ireland became inextricably linked with that of one ambitious politician. His uses of the G.P.O. in particular revealed a perceptive understanding of the political uses of classical architecture and urban space.

Neolithic and Bronze age migration to Ireland and establishment of the insular Atlantic genome

The Neolithic and Bronze Age transitions were profound cultural shifts catalyzed in parts of Europe by migrations, first of early farmers from the Near East and then Bronze Age herders from the Pontic Steppe. However, a decades-long, unresolved controversy is whether population change or cultural adoption occurred at the Atlantic edge, within the British Isles. We address this issue by using the first whole genome data from prehistoric Irish individuals. A Neolithic woman (3343–3020 cal BC) from a megalithic burial (10.3× coverage) possessed a genome of predominantly Near Eastern origin. She had some hunter–gatherer ancestry but belonged to a population of large effective size, suggesting a substantial influx of early farmers to the island. Three Bronze Age individuals from Rathlin Island (2026–1534 cal BC), including one high coverage (10.5×) genome, showed substantial Steppe genetic heritage indicating that the European population upheavals of the third millennium manifested all of the way from southern Siberia to the western ocean. This turnover invites the possibility of accompanying introduction of Indo-European, perhaps early Celtic, language. Irish Bronze Age haplotypic similarity is strongest within modern Irish, Scottish, and Welsh populations, and several important genetic variants that today show maximal or very high frequencies in Ireland appear at this horizon. These include those coding for lactase persistence, blue eye color, Y chromosome R1b haplotypes, and the hemochromatosis C282Y allele; to our knowledge, the first detection of a known Mendelian disease variant in prehistory. These findings together suggest the establishment of central attributes of the Irish genome 4,000 y ago.

Victorius vs Dionysius: the Irish Easter controversy of AD 689

Over the past few decades, the early medieval Easter controversy has increasingly been portrayed as a conflict between the ‘Celtic’ and the ‘Roman’ churches, limiting the geographical extent of this most vibrant debate to Britain and Ireland (with the exception of the disputes caused by Columbanus’ appearance on the Continent). Both are not the case. Before c.AD 800, there was no unanimity within the ‘Roman’ cause. Two ‘Roman’ Easter reckonings existed, which could not be reconciled, one invented by Victorius of Aquitaine in AD 457, the other being the Alexandrian system as translated into Latin by Dionysius Exiguus in AD 525. The conflict between followers of Victorius and adherents of Dionysius occurred in Visigothic Spain first, reached Ireland in the second half of the 7th century, and finally dominated the intellectual debate in Francia in the 8th century. This article will focus on the Irish dimension of this controversy. It is argued that the southern Irish clergy introduced the Victorian reckoning in the AD 630s and strictly adhered to that system until the end of the 7th century. When Adomnan, the abbot of Iona, converted to Dionysius in the late AD 680s and convinced most of the northern Irish churches to follow his example, this caused considerable tension with southern Irish followers of Victorius, as is impressively witnessed by the computistical literature of the time, especially the texts produced in AD 689. From this literature, the issues debated at the time are reconstructed. This analysis has serious consequences for how we read Irish history towards the end of the 7th century; rather than bringing the formerly ‘Celtic’ northern Irish clergy in line with southern Irish ‘Roman’ practise, Adomnan added a new dimension to the conflict.

Seaborne trade and the commercialisation of fifteenth- and sixteenth-century Gaelic Ulster

This study considers the frequently stated claim that the economy of Gaelic- speaking lordships in Ulster during the fifteenth and sixteenth centuries was predominately pastoral anduncommercialised, by drawing on a variety of sources not usually combined. It proposes that the increased European demand for fish and the growth of the fish industry across northern Europe played a crucial role in stimulating trade between the coastal areas of Ulster on the one hand, and Britain and continental Europe on the other. This led to the establishment of permanent markets and towns, which joined at least two new inland towns in the southern parts of the province, bringing about a commercial presence in most of the Ulster lordships before 1600. Gaelic Lords consolidated this development by building castles and friaries at these fixed trading places.