I did not enjoy the Christmas festivities this year: I sang no carols, ate no turkey and failed to watch It’s a Wonderful Life. There were two reasons. First, I received my DNA heritage results from a company I’d bunged £100 or so back in the autumn. My family had been greatly looking forward to this event, hoping for a revelation that I was part Igbo or Hausa or, better still, related somehow to the unfriendly pygmies of the western mountains in Papua New Guinea.