Blood of the Irish: What DNA Tells Us About the Ancestry of People in Ireland
Blood of the Irish
This article has been updated to include the latest research sequencing the genomes of remains of ancient Irish people , published at the end of 2015.
The Blood in Irish veins is Celtic, right? Well, not exactly. Although the history that used to be taught at school said the Irish were simply a Celtic people, related to the central European Celts, the truth is much more complicated, and much more interesting than that ...
Research done into the DNA of the Irish has shown that our old understanding of where the population of Ireland originated may have been misguided. Although the modern Irish have been shown to share many genetic similarities with Scottish and Welsh populations, and to differ somewhat from the English, due to repeated waves of migration to the island they also have close genetic relations with people further afield. In fact, some of the Irish's closest DNA links are with quite unexpected regions!
Irish origin myths confirmed by scientific evidence?
One of the oldest texts composed in Ireland is the Leabhar Gabhla, the Book of Invasions. It tells a semi-mythical history of the waves of people who settled in Ireland in earliest times. It says the first settlers to arrive in Ireland were a small dark people called the Fir Bolg, followed by a magical super-race called the Tuatha de Danaan (the people of the goddess Dana).
Most interestingly, the book says that the group which then came to Ireland and fully established itself as rulers of the island were the Milesians - the sons of Mil, the soldier from Spain. Modern DNA research has actually suggested that the Irish are close genetic relatives of the people of northern Spain.
What we do know is that the modern Irish are descended from a number of waves of migration with some ancestors coming from as far away as the Middle East and the Russian Steppes. Although it might seem surprising, it is worth remembering that in ancient times the sea was one of the fastest and easiest ways to travel. When the land was covered in thick forest, coastal settlements were common and people travelleled around the seaboard of Europe quite freely.
Early Origins of Irish DNA
The earliest settlers came to Ireland around 10,000 years ago, in Stone Age times. There are still remnants of their presence scattered across the island. Mountsandel in Coleraine in the North of Ireland is the oldest known site of settlement in Ireland - remains of woven huts, stone tools and food such as berries and hazelnuts were discovered at the site in 1972.
But where did the early Irish come from? For a long time the myth of Irish history has been that the Irish are Celts. Many people still refer to Irish, Scottish and Welsh as Celtic culture - and the assumtion has been that they were Celts who migrated from central Europe around 500BCE. Keltoi was the name given by the Ancient Greeks to a 'barbaric' (in their eyes) people who lived to the north of them in central Europe. While early Irish art shows some similarities of style to central European art of the Keltoi, historians have also recognized many significant differences between the two cultures.
Research into Irish DNA at the beginning of the twenty-first century suggests that the early inhabitants of Ireland were not directly descended from the Keltoi of central Europe. Genome sequencing performed on remains of early settlers in Ireland by researchers at Trinity University in Dublin and Queens University has revealed at least two waves of migration to the island in past millennia. Analysis of the remains of a 5,200 year-old Irish farmer suggested that the population of Ireland at that time was closely genetically related to the modern-day populations of southern Europe, especially Spain and Sardinia. Her ancestors, however, originally migrated from the Middle East, the cradle of agriculture.
Meanwhile, the research team also examined the remains of three 4,000 year-old men from the Bronze Age and revealed that another wave of migration to Ireland had taken place - this time from the edges of Eastern Europe. One third of their ancestry came from the Steppe region of Russia and Ukraine, so their ancestors must have gradually spread west across Europe. These remains, found on Rathlin Island also shared a close genetic affinity with the Scottish, Welsh, and modern Irish - unlike the earlier farmer. This suggests that many people living in Ireland today have genetic links to people who were living on the island at least 4,000 years ago.
You can link to the study here: http://www.pnas.org/content/early/2015/12/22/1518445113
Closest genetic relatives of Irish today
Today, the closest genetic relatives of the Irish in Europe are to be found in the north of Spain in the region known as the Basque Country. The Irish also share their DNA to a large extent with the people of Britain - especially the Scottish and Welsh.
DNA testing through the male Y chromosome has shown that Irish males have the highest incidence of the haplogroup 1 gene in Europe. While other parts of Europe have integrated contiuous waves of new settlers from Asia, Ireland's remote geographical position has meant that the Irish gene-pool has been less susceptible to change. The same genes have been passed down from parents to children for thousands of years.
This is mirrored in genetic studies which have compared DNA analysis with Irish surnames. Many surnames in Irish are Gaelic surnames, suggesting that the holder of the surname is a descendant of people who lived in Ireland long before the English conquests of the Middle Ages. Men with Gaelic surnames, showed the highest incidences of Haplogroup 1 (or Rb1) gene. This means that those Irish whose ancestors pre-date English conquest of the island are descendants of early settlers who probably migrated west across Europe, as far as Ireland in the north and Spain in the south.
You can read more about National Geographic's 2013 'Genographic' project in the west of Ireland here: http://voices.nationalgeographic.com/2013/11/21/the-genographic-project-returns-to-ireland-to-reveal-dna-results/
Irish and British DNA : a comparison
I live in Northern Ireland and in this small country the differences between the Irish and the British can still seem very important. Blood has been spilt over the question of national identity.
However, research into both British and Irish DNA suggests that people on the two islands have much genetically in common. Males in both islands have a strong predominance of the Haplogroup 1 gene, meaning that most of us in the British Isles are descended from the same stone age settlers.
The main difference is the degree to which later migrations of people to the islands affected the population's DNA. Parts of Ireland (most notably the western seaboard) have been almost untouched by outside genetic influence since early times. Men there with traditional Irish surnames have the highest incidence of the Haplogroup 1 gene - over 99%.
At the same time London, for example, has been a mutli-ethnic city for hundreds of years. Furthermore, England has seen more arrivals of new people from Europe - Anglo-Saxons and Normans - than Ireland. Therefore while the earliest English ancestors were very similar in DNA and culture to the tribes of Ireland, later arrivals to England have created more diversity between the two groups.
Irish and Scottish people share very similar DNA. The obvious similarities of culture, pale skin, tendency to red hair have historically been prescribed to the two people's sharing a common Celtic ancestry. Actually, in my opinion, it seems much more likely that the similarity results from the movement of people from the north of Ireland into Scotland in the centuries 400 - 800 AD. At this time the kingdom of Dalriada, based near Ballymoney in County Antrim extended far into Scotland. The Irish invaders brought Gaelic language and culture, and they also brought their genes.
How DNA reveals ancestry
This hub explains really well how DNA origins can be traced through the male Y chromosome:
Read more about the origins of the people of Ireland
Irish Characteristics and DNA
The MC1R gene has been identified by researchers as the gene responsible for red hair as well as the accompanying fair skin and tendency towards freckles. According to genetic research, genes for red hair first appeared in human beings about 40,000 to 50,000 years ago.
These genes were then brought to the British Isles by the original settlers, men and women who would have been relatively tall, with little body fat, athletic, fair-skinned and who would have had red hair. So red-heads may well be descended from the earliest ancestors of the Irish and British.
A spoof (and very funny) exploration into the characteristics of all Irish-blooded males can be read at this link: www.irishtimes.com/newspaper/weekend. Identified genes include IMG or the Irish Mother Gene and the GK (MF) S Gene Kelly-Michael-Flately-Syndrome which explains the inability of the Irish man to move his hips while dancing!