As I recall (no references handy, sorry--I'm at home waiting for the
furnace repairman) didn't Barry Hall measure mutation rate in the
presence of a lac analog, which would activate the lac operon but not
allow growth, and find that the rate was not enhanced? I heard him
speak at a seminar, and recall that this was a main reason for rejecting
the transcription-causes-mutation hypothesis.
Can anyone summarize current hypotheses about directed mutation? My
impression from his talk was that Barry's attempts to disprove
hypotheses had been so successful, he was basically left without one.
Mary Kuhner mkkuhner at genetics.washington.edu