That is too funny that you responded now, as I have 2 other tabs open with papers on the experiment. One from 2005, and one from 2007.
Have just downloaded them, and will start reading soon 🙂
I had also never heard of operons (multiple genes under control of a singe promoter) in eukaryotes. The dogma I was taught was: One gene, one promoter in eukaryotes. Operons only in prokaryotes.
So I was thinking it had to be a transcription factor change.
But apparently a small number of operons have been very recently identified in eukaryotes, so I have a 2002 and a 2004 paper I am looking at about that.
Fascinating stuff. I am never going to graduate.
Focus! You can read dog genetics articles once you graduate.