Irish Travellers are of Irish ancestral origin and have no particular genetic ties to European Roma groups, a DNA study has found.
The research offers the first estimates of when the community split from the settled Irish population, giving a rare glimpse into their history and heritage.
Researchers led by the Royal College of Surgeons in Ireland and the University of Edinburgh analysed genetic information from 42 people who identified as Irish Travellers.
The team compared variations in their DNA code with that of 143 European Roma, 2232 settled Irish, 2039 British and 6255 European or worldwide individuals.
They found that Travellers are of Irish ancestral origin but have significant differences in their genetic make-up compared with the settled community.
These differences have arisen because of hundreds of years of isolation combined with a decreasing Traveller population, the researchers say.
The findings confirm that the Irish Traveller population has an Irish ancestry and this comes at a time where the ethnicity of Travellers is being considered by the Irish State.
The team estimates the group began to separate from the settled population at least 360 years ago.
Their findings dispute the theory that Travellers were displaced by the Great Famine, which struck Ireland in 1845.
It is exciting to find that the Irish Travellers have been genetically isolated for such a considerable time. They hold great potential for understanding common diseases, not just within their own community but also more generally. I hope very much that further funding will allow us to study the genetics of the Travellers in more detail.
There are estimated to be up to 40,000 Travellers living in Ireland, which represents less than one per cent of the population.
Little is known about the group's heritage and there is scant documentary evidence of their history.
The study is published in the journal Scientific Reports.