Current Weiss Lab Members
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Bob Weiss, PhD
Principal Investigator, rsw26@cornell.edu
Bob is a Professor of Molecular Genetics in the Department of Biomedical Sciences and the Senior Associate Dean for the Graduate School (previously the Associate Dean for Research and Graduate Education in the College of Veterinary Medicine) at Cornell University. He received an A.B. in Biology from Wabash College in 1992 and a Ph.D. in Molecular Virology from Baylor College of Medicine in 1997. He then trained as a postdoctoral fellow in the Department of Genetics at Harvard Medical School with support from an American Cancer Society postdoctoral fellowship. In 2002, Bob joined the faculty of Cornell University. He lectures in the core veterinary curriculum, teaches a graduate course on genome maintenance mechanisms, teaches a course for all students at Cornell on cancer patient and research engagement in the community, and leads a research program aimed at dissecting how mammalian cells maintain genomic stability, using mouse models and an array of genetic, molecular, cell biological, and genomic technologies.
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Gerardo A. Arroyo Martinez
Graduate Student | gaa65
I’m a Ph.D. student in the Biochemistry, Molecular, and Cell Biology program. I was born and raised in Ponce, Puerto Rico, where I completed my undergraduate studies at the University of Puerto Rico-Ponce. Currently, my research focuses on studying the different roles of the 9-1-1 complexes during mammalian meiosis. Outside of the lab, I enjoy photowalks, swimming and watching musicals.
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Scott Butler
Research Support Specialist III | sdb9
Scott has worked at Cornell University for over 28 years. He also works in the PATh Facility (Progressive Assessment of Therapeutics) where he helps to develop and research in vivo cancer models to help
develop therapeutic treatments. His journey in science has been a twisting road but very rewarding. He studied Biology in college and worked summers as a research assistant at Cornell doing everything from basic lab techniques to milking cows, but he has been doing science ever since he can remember. “My father was a professor in Animal Science, and he would take me with him to the farm or the lab all the time. After college I started working on a research farm here at Cornell. From there I moved to the College of Veterinary Medicine doing hepatitis research on woodchucks. I learned many of my lab techniques here. I then went on to manage a lab doing research involving hypertension and brain regulation of cardiac abnormalities. This is where I received most of my experience in managing a research lab as well as becoming an expert in rodent surgical procedures. I am currently the husband of a nurse, the father of a high school senior daughter, and at the mercy of 3 dogs. Aside from my family, my real passion is fly fishing.”
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Dr. Catalina Pereira
Postdoctoral Researcher | cp556
Catalina received her B.S. in Biology from Mount St. Mary’s University, in Los Angeles in 2013. In 2014 she began her graduate studies in the field of Biochemistry, Cellular, and Molecular Biology at Cornell University and joined the Weiss lab. She received her her PhD in 2020, for her research on the role of the 9-1-1 complex/alternative 9-1-1 complexes in checkpoint signaling and mammalian meiosis.
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Michelle Liu
Graduate Student |ml2224
Michelle graduated with a BA in biology from Oberlin College and joined the Genetics, Genomics and Development program at Cornell in 2021. Her research is focused on understanding the chemosensitivity of testicular germ cell tumors. When not in lab, she enjoys indulging in her plant addiction and dabbling in crafts.
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Andy Yu-Wei Chang
Graduate Student | yc944
Andy is originally from Taiwan and graduated with his M.S. in Biochemistry and Molecular Biology from National Yang-Ming University in Dr. Cheng-Wen Wu’s lab. He worked as a research assistant at National Taiwan University before joining Cornell’s Biomedical & Biological Sciences PhD program in 2021. Currently, his project is focused on the roles of SIRT1 medicated exosomes in breast cancer progression. Outside of the lab Andy likes to watch and attend baseball games.
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Kelsey Jones
Laboratory Technician IV | kej42
An upstate NY native, Kelsey graduated with a BA in Biology from Binghamton University in 2018. She then went on to work in a flow cytometry/agricultural lab setting prior to joining the Weiss Lab in fall of ’21 as a technician. She enjoys being able to facilitate/participate in furthering the field of cancer research. Outside of the lab Kelsey enjoys hanging out with her kitties, corgi and chickens, baking, and playing video games.
Pronouns: She/They
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Max Chen, DVM
Graduate Student | amc492
Max graduated with a DVM from National Chung Hsing University in Taiwan in 2022 before joining the Biomedical & Biological Sciences PhD program at Cornell. His project will focus on the roles of SIRT5 in tumor angiogenesis. Outside of the lab Max enjoys watching shows, playing games, and spending time with his cat.
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Michael Guo
Undergraduate Student | mg955
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Ilana Livshits
Undergraduate Student | il292
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Ashton Joseph
Undergraduate Student | aaj55
Ashton is majoring in HBHS and plans to minor in Microbial Sciences. He is in the class of 2027 and joined the Weiss lab in the fall of 2024. He is from Buffalo, NY and is also on the pre-med track. Outside of academics, he enjoys reading, playing games, and hanging out with friends.
Pronouns: He/Him/His
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Aidan Quinn
Undergraduate Student | amq23
Aidan is a Biological Sciences Major at the College of Agriculture and Life Sciences, pursuing the pre-medical track as a member of class of 2028. He joined the Weiss Lab in Spring of 2025. Originally from Long Island, New York, he likes to stay active at the gym and listen to music in his free time.
Pronouns: He/Him/His
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Elijah Bacchus
Undergraduate Student | eab356
Elijah is a sophomore in the Human Biology, Health, and Society major from New York City and joined the Weiss Lab in the Spring of 2025. Following graduation, Elijah plans to attend medical school. He enjoys juggling, watching movies, playing video games, and building Legos.
Pronouns: He/Him/His