Colm Ó Dúshláine writes,
I got a tattoo of a double helix on my arm (see attached) to "mark" the occasion of the submission of my PhD thesis. I felt I should have something that records my passion for genetics in the same way that another one I have, a celtic knot, records my ancestry. Anyway, a year later, my research group starts up a collaboration with James Watson, co-discoverer of the structure of DNA. I thought it was pretty cool that I had the chance to meet him, so I showed him the tattoo! I was pleasantly surprised (and also felt VERY nerdy) when he at first couldn't believe it was real!!