Editing Irish Travellers (section)

=== Population genetics ===
Genetic evidence reported in 2000 regarding Irish Travellers supported Irish ancestry; several distinct subpopulations; and the distinctiveness of the midland counties due to Viking influence.<ref name="ncbi.nlm.nih.gov">{{cite journal |last1=North |first1=Kari E. |last2=Martin |first2=Lisa J. |last3=Crawford |first3=Michael H. |date=September–October 2000 |title=The origins of the Irish travellers and the genetic structure of Ireland |journal=Annals of Human Biology |volume=27 |issue=5 |pages=453–465 |doi=10.1080/030144600419297 |issn=1464-5033 |pmid=11023116 |s2cid=1663372 }}</ref> In 2011, researchers at the [[Royal College of Surgeons in Ireland|Royal College of Surgeons]] in Dublin and the [[University of Edinburgh]] analysed DNA samples from 40&nbsp;Travellers. The study provided evidence that Irish Travellers are a genetically separate Irish ethnic minority which has been distinct from the settled Irish community for at least 1,000&nbsp;years: The report claimed that Travellers are as distinct from the settled community as [[Icelanders]] are from [[Norwegians]].<ref>{{cite news |last=Hough |first=Jennifer |date=2011-05-31 |title=DNA study: Travellers a distinct ethnicity |website=irishexaminer.com |location=Blackpool, IE |publisher=Irish Examiner |url=http://www.irishexaminer.com/ireland/health/dna-study-travellers-a-distinct-ethnicity-156324.html |access-date=2016-05-17 |quote=Separated from the settled community between 1,000&nbsp;and 2,000&nbsp;years ago.}}</ref>

In 2017 a further genetic study using profiles of 50&nbsp;Irish Travellers, 143&nbsp;European Roma, 2,232&nbsp;settled Irish, 2,039&nbsp;British and 6,255&nbsp;European or worldwide individuals, confirmed ancestral origins from within the general population of Ireland. An estimated time of divergence between the settled population and Travellers was set at a minimum of 8&nbsp;generations ago, with generations at 30&nbsp;years, hence 240&nbsp;years and a maximum of 14&nbsp;generations or 420&nbsp;years ago. The best fit was estimated at 360&nbsp;years ago, giving an approximate date in the 1650s.<ref>{{cite news |title=Travellers as 'genetically different' from settled Irish as Spanish |newspaper=[[Irish Times]] |url=https://www.irishtimes.com/news/science/travellers-as-genetically-different-from-settled-irish-as-spanish-1.2969515}}</ref>

Irish Travellers are not an entirely homogeneous group, instead reflecting some of the variation also seen in the settled population. Four distinct genetic clusters were identified in the 2017 study, and these match social groupings within the community.<ref name=Gmelch-1991-1986>{{cite book |last=Gmelch |first=Sharon |year=1991 |orig-year=1986 |chapter=Preface |title=Nan: The life of an Irish Travelling woman |type=Biography |edition=Reissue with changes |location=Long Grove, IL |publisher=Waveland Press |isbn=978-0-88133-602-3 |chapter-url=https://books.google.com/books?id=9foVAAAAQBAJ&pg=PA11 |pages=11–14}}</ref>

Irish Travellers, particularly those that experienced a life of nomadism prior to the 2002 Irish legislation that altered living conditions, exhibit distinct gut microbiota compared to other Irish citizens, which is comparable to gut microbiomes observed in non-industrialized societies.<ref name="Keohane-2020">{{cite journal |doi=10.1038/s41591-020-0963-8 |title=Microbiome and health implications for ethnic minorities after enforced lifestyle changes |journal=Nature Medicine |volume=26 |issue= 7|pages=1089–1095 |year=2020 |last1=Keohane|first1=David M. |last2=Ghosh|first2=Tarini Shanka |last3=Jeffery|first3=Ian B. |last4=Molloy|first4=Michael G. |last5=O’Toole|first5= Paul W. |last6=Shanahan|first6=Fergus|pmid=32632193 |s2cid=220376175 |doi-access=}}</ref>

====Genetic disease studies====
Genetic studies by Miriam Murphy, David Croke, and other researchers identified certain genetic diseases such as [[galactosemia]] that are more common in the Irish Traveller population, involving identifiable [[allele|allelic]] mutations that are rarer among the rest of the community.

Two main hypotheses have arisen, speculating whether:
* the prevalence resulted from marriages made largely within and among the Traveller community,
or
* suggesting shared descent from an [[Founder effect|original Irish carrier]] long ago with ancestors unrelated to the rest of the Irish population.<ref name=Murphy-McHugh-etal-1999-07>{{cite journal |last1=Murphy |first1=Miriam |last2=McHugh |first2=Brian |last3=Tighe |first3=Orna |last4=Mayne |first4=Philip |last5=O'Neill |first5=Charles |last6=Naughten |first6=Eileen |last7=Croke |first7=David T. |date=July 1999 |title=Genetic basis of transferase-deficient galactosaemia in Ireland and the population history of the Irish Travellers |journal=European Journal of Human Genetics |volume=7 |issue=5 |pages=549–554 |pmid=10439960 |issn=1476-5438 |s2cid=22402528 |doi=10.1038/sj.ejhg.5200327 |doi-access=free |url=http://www.nature.com/ejhg/journal/v7/n5/pdf/5200327a.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://www.nature.com/ejhg/journal/v7/n5/pdf/5200327a.pdf |archive-date=2022-10-09 |url-status=live}}</ref>
In their conclusion Murphy, McHugh, ''et al''<ref name=Murphy-McHugh-etal-1999-07/> write that:
:The fact that Q188R is the sole mutant allele among the Travellers as compared to the non-Traveller group may be the result of a [[founder effect]] in the isolation of a small group of the Irish population from their peers as founders of the Traveller sub-population. This would favour the second, endogenous, hypothesis of Traveller origins."<ref name=Murphy-McHugh-etal-1999-07/>{{rp|style=ama|p=553}}

More specifically, they found that Q188R was found in 100% of Traveller samples, and in 89% of other Irish samples, indicating that the Traveller group was typical of the larger Irish population.<ref name=Murphy-McHugh-etal-1999-07/>{{rp|style=ama|p= 552 §discussion}}