Believe or not, studying yeast is actually a hobby. However, it is the hobby that really drew me into the home brewing hobby. Without yeast, home brewing would have been little more than a passing fad. I plated my first brewing yeast culture in 1993. I brewed and maintained a yeast bank on agar slants for a decade before taking an extended hiatus from the hobby. It was my desire to play with yeast again that drew me back into the hobby.
With respect to yeast genetics, well, my B.S. and M.S. degrees are in computer science (the computer engineering side of computer science). Bioinformatics is an area of computer science in which I have professional interest.
With that said, I did not wake up one day and know all of this information. It was a matter of applying myself over an extended period of time. I have basically passed the 10,000 hour mark that Malcom Gladwell writes about in his book entitled "Outliers: The Story of Success." A.J. DeLange is an electrical engineer by training, John Palmer is a metallurgical engineer by training, and Charlie Papazian is a nuclear engineer by training, but they all managed to become experts in areas of brewing that are completely unrelated to their formal training.