“If you're doing any sort of DNA studies, PCR is just the thing you do,” says pioneering genomics researcher Eric Green. In this process, scientists put their desired genetic sequence into the genomes of bacteria, which then divided and replicated both themselves and the introduced genetic code. After that fateful weekend in his cabin, Mullis returned to work at Cetus Corporation in Emeryville, California. Meanwhile, Shirley Kwok, a scientist at Cetus, was applying PCR to study HIV but was getting annoyed with the process. White ended up running the PCR division there, along with over a hundred Cetus scientists he took with him.