Danielle Sawyer, Ph.D.

MS III
College of Medicine – Tucson
Year Entered Program: 
2019
Grad Year: 
2025
Degrees Received: 

A.S. Biology and A.S. Natural Science, Santa Rosa Junior College (2015)

B.S. in Cellular Biology, University of California, Davis (2017)

Ph.D. in Cancer Biology, University of Arizona, Tucson (2024)

Thesis Advisor: 
Joann Sweasy, Ph.D.
Thesis Research: 

My research focused on DNA Polymerase beta (Pol beta) which is a polymerase that lacks inherent proofreading capacity and plays a major role in DNA repair. Base excision repair is responsible for the removal of 20,000-50,000 DNA base lesions per cell per day, and when dysfunctional it can drive genomic instability and cellular transformation. My work studied human germline variants of Pol beta seen in patients with cancer, using kinetic studies as well as cellular approaches in order to further understand how these variants might function differently than the inherent WT enzyme. The goal being to understand whether these variant could contribute to the formation of cancer in vivo.

About Me: 

I grew up in Windsor, a small town in Northern California. As a first generation college student, I attended a community college prior to transferring to University of California, Davis. My experience as a first-generation student trying to navigate the road to Medical School has made me passionate about mentoring and supporting other first generation or non-traditional students. Are you a pre-medical student reading this? If so, please reach out with any questions or to set up a meeting. 

My research career began at The Buck Institute in Dr. Brian Kennedy's lab, where I worked with Dr. Mark McCormick studing genes that may contribute to aging and longevity. I later performed research through University of California, Davis in the McKenney and Ori-McKenney labs, where we studied microtubule dynamics and the interaction of microtubules with their associated proteins (MAPs), in vitro. My clinical experiences include working as a medical scribe at a Hematology/Oncology clinic in Northern California. My passion to help and impact patients directly, and my desire to understand underlying disease mechanisms and help patients on a more global scale, lead me to pursue a career as a Physician-Scientist at The University of Arizona, College of Medicine - Tucson.

For my Ph.D., I worked in the lab of Dr. Joann Sweasy, Ph.D. at the University of Arizona Cancer Center. The focus of my work was to study germline variants of DNA polymerase beta that exist in the human population and are seen in patients with cancer. My work revealed a novel S180R variant of DNA polymerase beta that exhibits altered kinetcs - it is slow to incorporate nucleotides but it also has the propensity to incorporate mutations into DNA. This suggests that this variant could be contributing to the formation of cancer in patients harboring this mutation. My overall research goals include working to understand genetic mutations that drive cancer formation, understand drug resistance mechanisms, as well as develop precision medicine therapies. 

In my spare time, I love to bake, I enjoy watching horror films, and I love to dance. In fact, my husband and I have been taking Ballroom dance lessons - the west coast swing and salsa are our current favorites! 

Honors & Awards: 
  • Outstanding Senior Award, University of California, Davis. 2017 
  • ARCS Foundation, Eller Memorial Scholar in Memory of Elizabeth Culley. 2022-2023 
  • ARCS Foundation, Marley Foundation Scholar in Memory of Milton "Bud" Webb. 2023-2024
  • T32 Integrative Cancer Research Scholar, 2023-2024
  • CRTEC Travel award (2023)
  • EMGS Travel award (2023)
  • Best Overall DNA Repair SNI Poster (2023, EMGS)
  • Distinction in Community Service (CUP Distintion Track), anticipated May 2026

Leadership Roles: 

  • UA MD-PhD Program Executive Committee (2023-2024)
  • MSTP Admissions Member (2021-2022)
  • Search Committee Member at UACOM-T (2022, 2023)
  • UACOM-T Admissions Member (2019-2020)
  • Founding member/Senior Mentorship Chair, FLI MedCats (2020-Present)
  • LCME Independent Student Analysis Committee Member (2023)
  • Focus Group Member (Interview Resources), AAMC (2023)
  • Co-director Tucson Refugee Education and Empowerment (TREE), (2020-2021)

Mentorship:

  • APSA Undergraduate Program, Mentor (2019 - 2024)
  • Prescribe It Foward, Mentor (2019 - 2024)
  • Medical Directive: University of Arizona Chapter, Mentor (2020 - Present)
  • ASU Pre-Health Program, Mentor (2022)

Panel and Guest Speaker Invitations:

  • American Physician Scientist Association (APSA) (2020, 2021, 2023, 2023, 2024)
  • American Women's Medical Association (AMWA) (2019, 2022)
  • Santa Rosa Junior College Foundation (2015, 2018, 2019)

University of Arizona Panelist and Speaker Invitations: 

  • U of A FACES in Health Professions (2023)
  • U of A Physiology Club (2022)
  • U of A AMSA Chapter (2022)
  • U of A Honors College (2021, 2022)
Selected Publications: 

Monroy, B.Y., Sawyer, D.L., Ackermann, B.E. et al. Competition between microtubule-associated proteins directs motor transport. Nature Communications 9, 1487 (2018) doi:10.1038/s41467-018-03909-2

Robbins, C. E., Patel, B., Sawyer, D. L., Wilkinson, B., Kennedy, B. K., &; McCormick, M. A.  Cytosolic and mitochondrial trna synthetase inhibitors increase lifespan in a GCN4/ATF-4-dependent manner. IScience (2022). https://doi.org/10.1016/j.isci.2022.105410

Sawyer, D.L., Gratreak, B.D. Medical schools must do more to open the door to first generation and low income students. BMJ (2022); 377 :o1246 doi:10.1136/bmj.o1246

Sawyer, D.L., and Sweasy, J.B. DNA Polymerase Beta in the Context of Cancer. Critical Reviews in Oncogenesis (2022); https://doi.org/10.1615/CritRevOncog.2022043477

Staroschak, C., and Sawyer, D. L. How medical schools can better support students through pregnancy and parenthood. BMJ (2023); 381:p1155 doi: https://doi.org/10.1136/bmj.p1155

Fijen C, Chavira C, Alnajjar K, Sawyer D.L, Sweasy J.B. Collapsed State Mediates the Low Fidelity of the DNA Polymerase β I260 Mutant. Biochemistry. (2024 Oct 1); 63(19):2414-2424. doi: 10.1021/acs.biochem.4c00263. 

Sutton, T.B., Sawyer, D.L., Naila, T., Sweasy, J.B., Tomkinson, A.E., Delaney, S. Global Screening of Base Excision Repair in Nucleosome Core Particles. DNA Repair (2024): https://doi.org/10.1016/j.dnarep.2024.103777.