COVID-19 Updates

Visit UC San Diego's Coronavirus portal for the latest information for the campus community.


Tatum Simonson, PhD

Tatum Simonson, PhD 
Associate Professor and John B. West Endowed Chair in Respiratory Physiology
Division of Pulmonary, Critical Care, and Sleep Medicine, UC San Diego School of Medicine
Principal Investigator
UCSD Profile
Dr. Simonson applies integrative physiological genomics approaches to understand systems-level responses to environmental stress in diverse populations. Her research provides evidence for genetic adaptations to high altitude and associations among these factors, molecular functions, and physiological traits. In addition to her research in the highlands of Tibet and Peru, her team studies natural variation in human responses to environmental challenges and aims to understand the contributions of genetic and epigenetic factors to variation in hypoxia-related disease states (e.g., altitude illness, sleep apnea, and cardiometabolic diseases). These and related interdisciplinary efforts are coordinated through the recently developed Center for Physiological Genomics of Low Oxygen at UC San Diego.  


Esteban Moya, PhD
Project Scientist
Esteban is a Project Scientist interested in physiological responses to hypoxia in animal models and human populations living at high altitudes. He obtained his Ph.D. in Physiological Sciences at the P. Universidad Católica de Chile studying the carotid body, cardiorespiratory, and oxidative responses in an animal model of obstructive sleep apnea. Currently, his interests include understanding the consequences of sustained hypoxia on the neuroplasticity occurring in the neurons and glial cells of the brainstem areas that control the ventilation in rodents. As well as the genetic and physiological basis for the control of breathing in human populations living at high altitudes.

Katie A. O’Brien, PhD.
Marie Sklodowska -Curie Global Research Fellow
Katie is a Marie Sklodowska-Curie Global Research Fellow based between the University of Cambridge and UCSD. The aim of her current Fellowship is to characterise the high-altitude metabolic phenotype driven by unique Andean genetics. She completed her doctorate in 2017 on metabolic profile changes and effects of dietary nitrate supplementation in hypoxia at King’s College London under the supervision of Prof. Stephen Harridge.  During this time, she was a scientific investigator on the Xtreme Everest 2 research expedition. Following this, she worked as a postdoctoral researcher investigating drug induced mitochondrial toxicity in the context of hypoxia in the group of Dr Andrew Murray at the University of Cambridge and in collaboration with GlaxoSmithKline and AstraZeneca. 

James J. Yu
Ph.D. Student, Biomedical Sciences Graduate Program
James is a PhD student interested in identifying genetic, metabolic, and physiological variation in high-altitude populations that are adaptive in hypoxic (both chronic and intermittent) environments. He is interested in utilizing techniques and tools such as CRISPR, metabolomics, and hypoxic ventilatory response to investigate variation within these populations. He graduated from Duke University in 2016 and serves as a Medevac pilot and Platoon Leader in the Army Reserves. In his free time, he enjoys rock climbing and surfing.

Wanjun Gu
Research Data Analyst
Wanjun graduated from UC San Diego with majors in Chemical Engineering and Economics. He is interested in hypoxia physiology and population genomics. He is currently doing genomic, transcriptomic, and metabolomic analysis on Tibetans, Han Chinese, and Andeans. UCSD Profile


Elijah Lawrence
Postgraduate Research Assistant
Eli graduated cum laude from UCSD with a BS in Biochemistry and Cellular Biology. With his interests vested in molecular biology and human physiology, he has dedicated his college career to research and clinical work. He has been a part of the Simonson Lab for over four years and plans to continue his research in a clinical context as he pursues admittance into a variety of MD/Ph.D. programs. His ultimate goal is to contribute to the world of healthcare through both the study and practice of medicine as both a physician and a scientist. UCSD Profile

Mitchell Kong
Ph.D. Student, Department of Bioengineering

Mitchell is a Ph.D. student interested in identifying genetic mutations found in populations living in extreme conditions and linking those mutations to adaptive phenotypes. He seeks to apply engineering techniques to develop ways to maintain biological function despite environmental stress. Mitchell graduated from UCSD in 2020 with a B.S. in Bioengineering.

Caroline Gaeta
Graduate Research Assistant
Caroline graduated from UC San Diego (UCSD) in 2020 with a major in Human Biology. She is currently a Biology Master’s student in the BS/MS Program at UCSD. Her research focuses on hypoxia, Chronic Mountain Sickness, and epigenetics modifications such as DNA methylation. After graduating from her Master’s program, Caroline plans to apply for dental school in the hopes of becoming an orthodontist in the future. Outside of academia, Caroline enjoys baking, traveling, and spending time with her cat and two dogs. 

Mikael Fakhoury
Graduate Research Assistant
Mikael is a Biology Masters student and graduated in 2020 as a Human Biology major. He is interested in studying the inflammatory response involved in Chronic Mountain Sickness and intermittent hypoxia. After he obtains his Master’s in Biology, Mikael plans to continue onto medical school. Outside of academia, Mikael is an advisor for Global Medical Training at UC San Diego and enjoys helping the less fortunate in his community and abroad. His interests include hiking, rock climbing, and overall adventure. During the pandemic, he has focused on working out, reading, and overall self-care.

Zhijian Zhang
Graduate Research Assistant
Jack is interested in both the biological and computational components of cellular hypoxia as well as adaptations in genomics of high altitude populations and how these physiological and genetic changes affect their lives. In addition, he hopes to learn more about how current bioinformatics tools can contribute to the discovery of new knowledge in regards to cellular hypoxia. Outside of lab and classes, he enjoys playing the cello.

Jennifer Reeves
Undergraduate Research Assistant
Jennifer is a Human Biology major interested in physiological and genetic aspects of hypoxia with a focus on recurring biological pathways and how certain mutations induce phenotypic variation in high altitude populations. Outside of academia and personal endeavors, she enjoys cooking, boxing, and traveling. 

Marco Bauk
Undergraduate Research Assistant
Marco is a fourth-year Human Biology major interested in the physiological responses to hypoxia in high-altitude populations. He is narrowing his focus on whether certain functional variants of endothelin receptor genes are associated with specific medical conditions in Andean populations. Marco occupies his free time with water polo, ship restoration on the USS Midway, and sailing. 

Jeevan Singh
Undergraduate Research Assistant
Jeevan is a third-year Human Biology major with a minor in Chemistry. He is interested in investigating the body’s response to hypoxia at the molecular level and understanding how variation between populations can be used to advance precision medicine. His current research focuses on investigating functional variants of genes related to the Andean response to hypoxia using gene-editing technology. Outside the lab, Jeevan is a safety officer for the UCSD club lacrosse team and a member of AED. After graduating from UCSD, he plans to attend medical school. A San Diego native, Jeevan enjoys spending his free time playing lacrosse, mountain biking, and surfing. 

Santiago Fassardi
4th Year Undergraduate Research Assistant
Sago is a fourth-year Molecular Biology major. He is interested in studying the relationship between cancer and hypoxia in high-altitude populations at the genome and transcriptome levels. Outside of the lab, Sago enjoys reading about history, playing basketball, and walks on the beach.

Maianh Phan 
Undergraduate Research Assistant 
Maianh is a 4th-year Physiology and Neuroscience major interested in the comparative physiology of high altitude hypoxia. She is currently investigating the effects of hypoxia on Tibetan sheep and its relation with hypoxic effects on humans. After graduating, she will be in pursuit of obtaining a master's degree through UCSD’s BS/MS program and later planning on applying to medical school. Aside from academics, she enjoys spending time with her two dogs and is a proud member of the UCSD Kendo Team. 

Lab Alumni

Postdoctoral Fellows
Erica Heinrich, PhD   
Michael Tift, PhD
Pablo Catalan Serra, MD

Postgraduate Students
Robby Boparai
Jason Pan
Chang Han
William Wegeng
Adam Zhao
Medical Students
Lu Wu
Jeremy Sieker

Undergraduate Students
Christina Blaul
Matea Djokic
Gigi Yip
Sama Alpatty 
Dean Tan
Kevin Lin  
Chetan Potu         
Madison Calder                                            
Anh Bui

High School Students
Catie Boehmer 
Sarah Espinoza
Ian Xu

Lab Support


  Phoebe and Dudley


  Milou and Toto


Congratulations and farewell to previous postdoctoral fellow Mike Tift, who has accepted an Assistant Professor position at the University of North Carolina, Wilmington!

Congratulations and farewell to previous postdoctoral fellow Erica Heinrich, who has accepted an Assistant Professor position at the University of California, Riverside School of Medicine!

Congratulations to Christina Blaul, recipient of the Society for Advancement of Chicanos/Hispanics and Native Americans in Science Travel Award!

​Congratulations to Wanjun Gu, University of Tokyo Research Internship Program 2018 Recipient!

Congratulations to Christina Blaul, Ledell Family Undergraduate Research Scholarship Recipient 2018! 

Congratulations to Eli Lawrence, Ledell Family Undergraduate Research Scholarship AND Chancellor's Research Excellence Scholarships (CRES) 2017 Recipient!                

Congratulations to Eli Lawrence on his Palomar Pathmaker Internship!

Congratulations to Jason Jialei Pan on getting into Stanford MS in Environmental Engineering!

Congratulations to Chang Han on getting into Yale PhD in Biostatistics!

Congratulations to Ian Xu on getting into University of Pennsylvania for undergraduate studies with a major in Bioengineering!

Congratulations to Sago Fassardi on getting into UC San Diego BS/MS program in Biology!