Alice Chien Chang

Alice Chien Chang (March 14, 1950 – March 2, 2026) was a Taiwanese molecular biologist and neuroscientist. She taught at National Yang-Ming Medical College, National Yang-Ming University, and National Yang Ming Chiao Tung University. In 1976, she and her collaborators published research on the purification of a DNA polymerase from the extreme thermophile Thermus aquaticus; this work was later regarded as one of the key technical foundations that enabled the high-temperature cycling, automation, and commercialization of the polymerase chain reaction (PCR).

Background Chien graduated from the Department of Biology at Fu Jen Catholic University in 1972. She later pursued graduate studies in the United States, earning a master's degree in cell biology from the University of Cincinnati and a Ph.D. in molecular, cellular, and developmental biology from Iowa State University. She subsequently conducted postdoctoral research in microbiology at the East Carolina University School of Medicine. After returning to Taiwan in 1982, she joined National Yang-Ming Medical College, where she engaged in teaching and research in neuroscience for many years.

During her tenure within the Yang-Ming academic system, she served as director of the Institute of Neuroscience, director of the Neuroscience Research Center, and university librarian, before retiring in 2013.

Alice Chien was married to Chang Nan-chi. She died on March 2, 2026, at the age of 75.

Contributions to PCR In 1976, under the name Alice Chien, Chien co-authored the paper "Deoxyribonucleic acid polymerase from the extreme thermophile Thermus aquaticus" with David B. Edgar and John M. Trela in the Journal of Bacteriology. The study reported the purification of a stable DNA polymerase from Thermus aquaticus, a thermophilic bacterium, and found that the enzyme had an optimal reaction temperature of approximately 80 °C.

In 1988, Randall K. Saiki and colleagues introduced the thermostable DNA polymerase from T. aquaticus into PCR, noting that this change "greatly simplified" the procedure. Because the reaction could be carried out at higher temperatures, it also significantly improved specificity, yield, sensitivity, and the length of DNA fragments that could be amplified. Later review literature likewise noted that the introduction of thermostable polymerase eliminated the need to add fresh enzyme in every cycle and made automated PCR on thermal cyclers possible, thereby constituting a crucial step in the transformation of PCR from a conceptual method into a widely applied technology.

Selected publications