Fig. 1.

This cartoon was inspired by the 1996 Failla lecture delivered by the Author to the Radiation Research Society discussing base excision repair of radiation-induced free radical damage. The model of the baseball diamond based on Abbot and Costello’s skit “Who’s on First, What’s on Second, I Don’t Know’s on Third,” was used to describe the activities of the four sets of BER enzymes, the glycosylases (first base), AP endonucleases (second base), DNA polymerases (third base), and ligases (home plate), which was about the extent of what was known at the time. This cartoon jumps almost two decades to display in outline form our current knowledge of BER processing which has definitely come from the minor to the major leagues.