Some, perhaps.
However, one of the major haplotypes R1a1-1 dates back to the late upper Paleolithic, maybe 17 or 18K years ago. Of course R1a1-1 mutations occurred in Europe at varying times afterward.
Most of the ancestors of Europeans were living on the edge of the ice and south (in Europe) at the last glacial maximum.
I was being a bit facetious regarding genocide of "Europeans" though. The population of North America would probably have been much to sparse to make killing your neighbor hundreds of miles away worthwhile.
Whether it was a comet, disease, or whatever, the fact that they were here is not something the so-called native peoples are willing to contemplate, whether for spiritual or, more likely, economic reasons. Some people just like being victims because it is so profitable.