In 1996 I was asked to give a lecture to Glaxo, a large UK pharmaceutical company. The Chairman at the time was Sir Richard Sykes and the organisers were naturally curious to know if he and I were related. I had just begun to use the Y chromosome in other research so I thought I would ask Sir Richard, himself a scientist, for a DNA sample. He agreed and so I tested both of us. The system I was using was very crude by modern standards, with only four markers but it was enough to show that Sir Richard and I had identical and, as it turned out rather rare, Y chromosomes which had been inherited from a common ancestor, perhaps the original Mr Sykes. I extended the study to include 100 Mr Sykes from their traditional 'homeland' of Yorkshire in the north of England. 70% of the men I tested carried the same Y chromosome as Sir Richard and me. Surnames are the principal tool of the traditional genealogist but, not being a genealogist myself, I did not at first appreciate the usefulness of this discovery. Soon after the resulting paper from the Sykes study was published in 2000 I received a flurry of invitations to speak to genealogical societies from both the UK and the US. I was delighted to experience the enthusiasm and drive with which genealogists, especially in the US, adopted DNA testing and developed it to its present position as a routine tool in traditional genealogy.