I clipped off most of the article for the sake of the dinosaur bit, but I believe it was that there were some genetic differences. Of course this was a small population sample, so...
Mind you, the Celts extended south into Iberia and the Italian penninsula and east to what is now Ukraine, and travelled the Silk Road as well, so such a far ranging people are bound to have quite a bit of variation, and many could be just other peoples absorbed into a larger group culturally/linguistically..... (Celtic used to be the most widespread language group in Europe, now it teeters on the edge of extinction)
I left the publication site on top of the meme so with the article title it can be looked up for those wanting to read further.
