What does our DNA tell us about being Irish?
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Saint Patrick's Day is a time of year when those with Irish heritage around the world celebrate being Irish. With the launch of AncestryDNA in the UK & Ireland we have an opportunity to show a different view of Irishness using genetics.

Using DNA

With AncestryDNA, all customers receive a unique estimate of their 'genetic ethnicity' ? where in the world their ancestors may have lived hundreds to thousands of years ago, based on their DNA. For example, an AncestryDNA ethnicity estimate can tell someone how much of their DNA likely came from Ireland - anywhere from 0% to 100%. As the first results of UK & Ireland tests come through we can start to build up a picture of ethnicity estimates not just for individuals but averaged across all those born in the UK or Ireland*. What is particularly fascinating about the map below is that it has been compiled using just AncestryDNA results. It does not use historical data about migration patterns or self-reporting from customers about how Irish they think they are. What we are seeing on the map is just what the DNA tells us.

AncestryDNA Irish Ethnicity

Irish Ethnicity in Ireland

 Region Irish Ethnicity
Connacht 76.7%
Leinster 71.8%
Munster 71.4%
Ulster 51.9%

Average Irish Ethnicity Estimate across Ireland

Not surprisingly, the highest average Irish ethnicity estimates are found in Ireland. However, within Ireland we are seeing some provincial differences. Historically inward migration to Ireland has come from the south and east through Leinster and Munster. The genetics appears to agree with the history here. The highest estimates found anywhere in the UK & Ireland are found in Connaught with 76.7%, with Munster and Leinster on 71.4% and 71.8% The ethnicity estimate for Ulster is lower than the other provinces around 51.9%. This also is what you might expect but attributing the different estimate in Ulster to the 17th century plantation is perhaps too simplistic. The connections between Ulster and Scotland are deep going back many centuries and continuing to the present day. As a child growing up in Donegal, one of the best parts of the summer was the influx of Scottish cousins home for the holidays (it made for some epic football matches).

Irish Ethnicity in Scotland & Wales

Region Irish Ethnicity
Southern Scotland


Northern Scotland




Isle Of Man


Average Irish Ethnicity Estimate for Scotland, Wales and the Isle of Man

Moving across the Irish Sea we see those areas with close historical ties show higher Irish ancestry. Echoing the results in Ulster, Southern Scotland shows the highest Irish ancestry across Great Britain with an average of 46.6%. The short distance from Ireland to Scotland, 13 miles at one point, makes it a natural destination for many Irish emigrants. Glasgow, Paisley, Dumfries, are all places well known to Irish emigrants over the centuries and into modern times. Travelling down from Scotland we see Wales has the next highest Irish ancestry. Showing once again the close ties of the Celtic nations, the average Irish ancestry across Wales is around 31.3%. Let us not forget the most famous Irish immigrant from Wales was Maewyn Succat, who is perhaps better known to us today as Saint Patrick.

Irish Ethnicity in England

Region Irish Ethnicity


South Border


North West Midlands






South East


South West Midlands




Home North


South East Midlands




South Central


North East Midlands


South West




West Anglia


East Anglia


 Average Irish Ethnicity Estimate across England

Finally looking at England we see generally the lowest Irish ancestry across the UK and Ireland. Across England the average Irish ancestry ranges from 26.7% in Lancashire down to 15.4% in East Anglia. Once again perhaps we are seeing the echoes of history. The cities of Liverpool and Manchester have long been a destination for those leaving Ireland. Just as Scotland was natural destination for emigrants from Ulster, so too the boat to Liverpool' was a common refrain for many Dubliners seeking new opportunities. As I mentioned before, it is early days for these results. As more people take the AncestryDNA test in the UK & Ireland we will gain a much better understanding of the genetic makeup of these islands. It is certainly an exciting time with much to learn.   If you would like to learn more about AncestryDNA, or to order your kit, click here. Have you taken the AncestryDNA test' Please share your stories with us on Facebook and  Twitter or email [email protected].     *All AncestryDNA users in this study consented to participate in research.