Dr. Philip C. Hanawalt 

Stanford University (Retired 2017)

Tell us a bit about your scientific and educational background.

I grew up in Midland, Michigan, where I developed an interest in electronics. I carried out a research project on Wheatstone Bridge Circuits, which earned an Honorable Mention in the annual Westinghouse Science Talent Search in 1949. That, in turn, led to a scholarship for one year at Deep Springs College, an unusual school on a ranch in California, with a work/study program and the expectation that students would “dedicate themselves to lives of service to humanity.” I was planning for an eventual career in physics, but a faculty member encouraged me to consider the nascent field of biophysics, which was attracting physicists to mechanistic biology.

I completed my undergraduate studies at Oberlin College with a physics major; then earned my Ph.D. in biophysics at Yale University, where I carried out graduate study on the responses of bacteria to ultraviolet radiation and obtained evidence for DNA repair. I then spent several years in Denmark with an NIH postdoctoral fellowship in the Microbiology Department at the University of Copenhagen, where I discovered mechanisms for regulation of the bacterial DNA replication cycle. I received a fellowship from the American Cancer Society for a third year of postdoctoral study, in molecular biology at the California Institute of Technology in Pasadena. I joined the faculty at Stanford University in 1961, as a Research Biophysicist and Lecturer; then, in 1965, an appointment to tenured Associate Professor in the Department of Biological Sciences. I was promoted to Professor in 1970, and I was accorded the Morris Herzstein Professorship in Biology in 2009. 

What do you see as the greatest value or most rewarding aspect of your scientific work?

I am indebted to a remarkable group of talented graduate students (and undergrads!) who have worked in my laboratory at Stanford. One of the most rewarding aspects of my career has been to mentor these students and to share in their research successes. My postdoctoral colleagues and research associates have also been valuable to my fulfillment in academia, with productive ideas and participation in the instruction of students, contributing to our leadership in the field of genomic maintenance.

In 1962 my first two graduate students (of 29 eventually) joined me to compare aspects of DNA replication in Esherichia coli under normal growth conditions with that following UV irradiation. Normally replicating fragments of DNA were preferentially sensitive to shearing at the growing point; while in UV-irradiated cells the nascent DNA appeared in “patches” within parental DNA and did not exhibit this sensitivity. We had discovered “repair replication” with co-discovery of the ubiquitous pathway of excision-repair. Several decades later the sub-pathway of transcription-coupled DNA repair was revealed in mammalian cells, yeast and bacteria, through collaborative studies in my group. Annual retreats (which we termed “advances”) were held for critical evaluation of all projects underway, with one or more guests from other research groups to add new insights and to “keep us honest”. Also rewarding for me were meetings that I organized or co-organized in the field of DNA repair, of which the first was the workshop on “Molecular Mechanisms for DNA Repair” at Squaw Valley in 1974, and then the 9th ICEM in San Francisco in 2005. 

What initially drew you to the EMGS? 

I was aware of the EMS and the involvement of Alex Hollaender and Matt Meselson in its founding. I thought that the Society was largely focused upon the specialized area of mutation testing (eg. Ames test) to reveal carcinogenic chemicals and environmental toxins. Then I was invited to speak in a symposium at the 1989 annual meeting in San Francisco, where I was pleased to learn that the EMS was in fact at the crossroads of studies on basic mutagenic mechanisms, genetic toxicology and governmental regulation of exposures to toxic substances. So I joined the Society and was soon appointed to Chair the Future Directions Committee 1990-’92, and then served as Program Chair/President 1993-’94, and was Chair of the Hollaender Outreach Committee 2011-’14. I also served on the Committee to consider the name change to EMGS. 

How has EMGS impacted your professional development? 

The EMS (EMGS) enriched my professional development, as I appreciated that it is the appropriate professional "home" for researchers in the field of DNA repair: it places them in the context of the broader genetic, societal, and regulatory issues raised from their studies. In return, the wisdom provided from basic research on cellular processing of damaged DNA is essential to mechanism-based decisions in the domain of genetic toxicology. Reference my Commentary in Evironmental and Molecular Mutagenesis 51: 890-896 (2010) titled “Growing up with DNA Repair and Joining the EMS”. 

What advice would you offer to students or early career investigators? 

Students and early career investigators should attend annual meetings of the EMGS and take advantage of the opportunities to meet experts in the three major domains of activity in the Society. They should also attend the Sigs in the areas of their potential interest.

They should get to know the leaders in their areas of interest to obtain valuable advice and potential mentorship as their careers develop. They should develop confidence in the value of their original ideas and opportunities to contribute to EMGS activities, by presenting posters and/or platform talks in the annual meetings. 

What involvement opportunities with EMGS have you found to be the most rewarding? SIGs, awards, etc.

Most rewarding to me have been the Sigs on DNA repair, and on epigenetics, and the Hollaender Committee. It has been fulfilling to participate in many Hollaender conferences and courses in South America. 

What are the most rewarding connections you have made since joining EMGS?

Of course I have appreciated the opportunities to interact with my DNA repair colleagues, but have also gotten to know members in the other areas represented in the EMGS … David DeMarini, George Douglas, Rosie Elespuru, Patricia Ostrowski, and many others, sadly of whom some are no longer with us. 

What do you think the greatest scientific achievement in history has been?

There have been so many great scientific achievements in so many areas that it is impossible to select the greatest.

Certainly the classic X-ray crystalography of DNA and her conclusion that the molecule is a helix was a seminal contribution from Rosalind Franklin, and the base pairing rules discovered by Erwin Chargaff were also essential to the development of the double-helical DNA model by Watson and Crick. 

If you could meet any scientist, past or present, who would it be and what would you talk about?

I would want to meet the brilliant Albert Einstein, to experience his scientific and mathematical insights, but also to appreciate his broad understanding and sensitivity to issues of humanity. I appreciate many of his quotes, including, “The only life worth living is a life in the service of others.” 

If you were not a scientist, what would you be doing?

If I were not a scientist, I would decide that I would be a scientist. Otherwise, I enjoy the musical arts, but probably could not make a living in that field.