Kary Mullis, PhD, the scientist who shared the 1993 Nobel Prize in Chemistry for his invention of the Polymerase Chain Reaction (PCR) at Cetus during the 1980s, has died from pneumonia at the age of 74. After leaving Cetus, Mullis served as a consultant for several biotech firms and founded a company called Altermune, which worked on developing treatments for drug-resistant pathogens.

Mullis was also a controversial figure who reportedly believed in astrology and disagreed with the majority of other scientists in that he did not accept that climate change was a problem or that HIV caused AIDS.

Mullis leaves behind a wife, Nancy, three children, and two grandchildren.