Geneticists: English, Irish, Scottish and Welsh Are Same People

According to an article in the New York Times, the DNA of individuals throughout the United Kingdom is so strikingly similar that the people of England, Scotland, Ireland, and Wales may all be descended from the same majority population that has existed on the islands for thousands of years and may not be descended from different peoples at all. Will we be able to put to rest the idea that England, Scotland, and Wales are separate independent countries?