... is a subject in which I have nil competence. And I haven't been able to obtain and read the widely reported Nature article (March 19, I think) about the genetic composition of Great Britain and Northern Ireland; I have had to rely on the reports in the 'broadsheet' papers.
But I feel two main problems (which of course may be dealt with in the full article). Firstly, the statement that "there is little Roman DNA in the British genetic make-up". You see, I don't even understand what such a negative actually means in this context. "Roman", in the first four centuries of the Christian Era, refers to people who could have come from the whole Mediterranean region. "Roman" soldiers and merchants came from anywhere between our Portugal and our Iraq; our Scotland and our Algeria. Many of them will never have visited Rome.
But more: if "Roman" is, on the contrary, intended to mean "only from the city of Rome", the problem is just as great. By the first century, Rome was a gigantic multiracial mix rather like modern London or New York. Even if everyone who came here between 40AD and 400 AD did come physically from the city of Rome and nowhere else, that, surely, still would not offer the investigator a single and simple genetic pattern to recognise or to fail to recognise.
Secondly: the investigators say they were surprised that "Celtic" turns out genetically to be a totally meaningless term. I am immensely surprised by their immense surprise. The "Celtic" myth was exploded in the 1990s at the latest. The word as currently used to bracket together the peoples of Brittany, Cornwall, Wales, Man, Scotland, and Ireland, or to refer to the pre-Roman Iron Age inhabitants of Great Britain, is devoid of significatory content except in as far as it may retain linguistically a usefulness based upon the fact that it has conventionally come to denote two groups of similar languages. That convention, of talking about "the Celtic languages", itself goes no further back than 1707, when the Welsh scholar Edward Lhuyd invented it. As long ago as 1998, Simon James wrote "Society as a whole simply accepts Celtdom as a fact, and has made it part of itself. Scholars started the Celtic hare running. The hare has now turned into a chimera, and the debate over how to kill it - if we can, and if we have the right to try - is only just beginning." If people, even academics, persist in being misled into thinking that the term does have any substance, it might be better for the philologists to dream up a replacement term.
And can it be that this 'surprising discovery' is another example of the dividedness of the modern Academy; a world in which geneticists do not read archeologists? I'll stick my neck yet further out and say: a world in which 'scientists' are too grand to bother with 'historians'?
Can anybody supply me with a link to this article? If I have been completely, comprehensively, unfair, It's my duty to admiy it!
Footnote: The alleged distinctiveness of 'Celtic Christianity' was disputed by Kathleen Hughes in 1981 followed by many since; Professor Thomas Charles-Edwards of this University has written dismissively of "that entity beloved of modern sectarians and romantics, but unknown to the early Middle Ages - 'the Celtic Church'."