Genetics and the Origins of the Irish


Population genetics, principally using Y‐chromosome and mitochondrial deoxyribonucleic acid (DNA), has provided many novel insights into Ireland's past. These inlcude broad issues of early time‐frame including the origin of the first Irish 9000 years before present, as well as the population impact associated with later events such as the appearance of Celtic culture and the Viking invasions. Furthermore, the Y‐chromosome in combination with surname information has also allowed questions of more recent nature and smaller scale to be addresssed including the levels of patrilineal kinship in early medieval Irish kingdoms and the origin and subsequent history of Irish surnames themselves.

Keywords: Ireland; Y‐chromosome; surnames; mitochondrial DNA; population genetics

Figure 1.

Geographic distribution of the Y‐chromosome R1b3(R1xR1a1) haplogroup across the British Isles. The frequency generally increases from Southeast to Northwest, reaching near fixation (100%) in some parts of Western Ireland. Map drawn using data from Capelli et al. and Moore et al..



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Further Reading

Cavalli‐Sforza LL and Menozzi PAP (1994) The History and Geography of Human Genes. Princeton, NJ: Princeton University Press.

Croke DT (2000) Genetic archaeology and the origins of the Irish population. Irish Journal of Medical Science 169: 258–261.

Cunliffe B (2001) Facing the Ocean: The Atlantic and Its People. Oxford: Oxford University Press.

Duffy S (2000) The Concise History of Ireland. Dublin: Gill and Macmillan.

Helgason A, Sigurethardottir S, Gulcher JR, Ward R and Stefansson K (2000) mtDNA and the origin of the Icelanders: deciphering signals of recent population history. American Journal of Human Genetics 66: 999–1016.

Helgason A, Sigurethardottir S, Nicholson J et al. (2000b) Estimating Scandinavian and Gaelic ancestry in the male settlers of Iceland. American Journal of Human Genetics 67: 697–717.

Jobling MA (2001) In the name of the father: surnames and genetics. Trends in Genetics 17: 353–357.

Jobling MA, Hurles ME and Tyler‐Smith C (2004) Human Evolutionary Genetics: Origins, Peoples & Disease. Oxford: Garland Science.

Jobling MA and Tyler‐Smith C (2003) The human Y chromosome: an evolutionary marker comes of age. Nature Reviews. Genetics 4: 598–612.

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McEvoy, Brian, and Bradley, Daniel G(Jul 2008) Genetics and the Origins of the Irish. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1002/9780470015902.a0020807]