Functional Epigenomics Lab team photograph.

Team bios

  • Vidya Ajay
  • Post-baccalaureate Research Education Program (PREP) scholar (2025-present)

Ajay earned a Bachelor of Technology in biomedical engineering from the Indian Institute of Technology, Hyderabad, in 2024 and completed a Master of Science in Engineering in biomedical engineering at Johns Hopkins University in 2025.

Ajay is a PREP scholar in a collaborative project between the labs of Fergus J. Couch, Ph.D., and Alexandre G. Maia, Ph.D. Her research focuses on leveraging her computational biology expertise to identify transcriptional dependencies in breast cancer using mammary epithelial cells, breast cancer cell lines and mouse models.

Ajay received the Academic Excellence Award at the Indian Institute of Technology, Hyderabad, in 2024. This award recognizes the highest GPA in the Department of Biomedical Engineering. She also received the India Connect Research Fellowship to perform research abroad at Nanyang Technological University Singapore in 2023.

  • Mihai G. Dumbrava
  • M.D.-Ph.D. student, Regenerative Sciences Ph.D. track, Mayo Clinic Graduate School of Biomedical Sciences (2022-present)

Dumbrava earned his Bachelor of Medical Sciences degree in biochemistry and pathology of human disease from the University of Western Ontario as a Scholar's Electives student. Under the mentorship of Martin Duennwald, Ph.D., he studied the mechanisms contributing to the onset of familial Parkinson's disease. He focuses on the protein DJ-1 using a yeast model, mammalian cells and patient tissues.

Through a ThinkSwiss fellowship, Dumbrava also pursued an internship in cancer biology research. He studied breast cancer therapeutic development at the University of Lausanne.

Dumbrava was accepted to the Mayo Clinic M.D.-Ph.D. Program in 2020. He joined the lab in 2022 to perform his Ph.D. studies through the Regenerative Sciences Ph.D. track, Mayo Clinic Graduate School of Biomedical Sciences.

Dumbrava received the Canadian Institutes of Health Research Doctoral Foreign Study Award for 2024-2026. His research focuses on understanding the drivers that promote the formation of invasive serous ovarian cancer and the key players in the tumor microenvironment that drive resistance to immunotherapy. His goal is to test the importance of the pathways that regulate the immunosuppressive milieu of ovarian cancer. He is optimizing microfluidic cancer cultures to modulate these interactions.

  • Sierra J. Hamernick
  • Ph.D. student, Regenerative Sciences Ph.D. track, Mayo Clinic Graduate School of Biomedical Sciences (2024-present)

Hamernick completed her Bachelor of Science degree in genetics, cell biology and development from the University of Minnesota, Minneapolis, in 2020. Her research in both her undergraduate studies and in industry focused on cellular approaches with primary cells and induced pluripotent stem cells to study various human conditions.

Hamernick is pursuing a Ph.D. as part of the Regenerative Sciences Ph.D. track, Mayo Clinic Graduate School of Biomedical Sciences. She joined the lab in 2024. Her research focuses on understanding cancer stem cells in ovarian cancer using single cell epigenomic profiling and 3D organoid cultures.

  • Amelia Mazzone, Ph.D.
  • Principal Research Technologist (2019-present)

After receiving her doctorate in 2001 from the University of Bari Aldo Moro in Italy, Dr, Mazzone came to Mayo Clinic in 2003 as a postdoctoral fellow in the lab of Nicholas F. LaRusso, M.D. She worked in Dr. LaRusso's lab until 2005, when she joined the lab of Gianrico Farrugia, M.D. She remained with Dr. Farrugia until 2019. Starting as a senior postdoctoral fellow, she was promoted to the rank of research associate.

In 2019, Dr. Mazzone joined the Functional Epigenomics Lab, where she is a principal research technologist. She holds the academic rank of instructor in medicine, Mayo Clinic College of Medicine and Science. Her technical expertise in cellular and molecular biology techniques includes RNA sequencing, assay for transposase-accessible chromatin using sequencing (ATAC-seq), multiple single-cell techniques and cell culture.

  • Wazim Mohammed Ismail, Ph.D.
  • Research Fellow (2020-present)

Dr. Mohammed Ismail graduated with dual degrees in computer science and biological sciences from Birla Institute of Technology and Science Pilani in Pilani, India. He earned a master's degree in bioinformatics and a Ph.D. in computer science from Indiana University Bloomington in 2020.

At Indiana University, Dr. Mohammed Ismail developed several algorithms using combinatorial approaches and probabilistic modeling to solve problems in genomics, such as clonal reconstruction from allele frequency time series estimated by whole-genome sequencing of an evolving cell population. Before embarking in the academic world, he worked in industry as a software engineer and developer.

Dr. Mohammed Ismail is a bioinformatics research fellow in the Functional Epigenomics Lab at Mayo Clinic. His primary research interest is solving computational challenges in genomic and epigenomic assay data interpretation, specifically in the developing field of single-cell genomics.

  • Clementine O. Payne
  • Ph.D. student, Biochemistry and Molecular Biology track, Mayo Clinic Graduate School of Biomedical Sciences (2025-present)

Payne earned an A.B. degree in biology with a minor in health studies from Bryn Mawr College. During her undergraduate studies, she conducted her thesis research under Tamara Davis, Ph.D., where she analyzed asymmetric DNA methylation patterns at imprinting and nonimprinting genes across different gestational ages and tissues.

After graduation, Payne joined the lab of Joseph E. Italiano Jr., Ph.D., at Boston Children's Hospital-Harvard Medical School as a research assistant. In that role, she investigated platelet biology and the impact of antisense oligonucleotides on thrombocytopenia. She also investigated the repair of DNA damage in megakaryocytes.

Payne joined the Functional Epigenomics Lab in 2025. Her research focuses on understanding the regulation of enhancer elements by macroH2A histone variants.

  • Jacqueline R. Vargas Ulloa
  • Ph.D. student, Regenerative Sciences Ph.D. track, Mayo Clinic Graduate School of Biomedical Sciences (2025-present)

Vargas Ulloa earned her Bachelor of Science in biotechnology with a chemistry minor at Arkansas State University. There, she researched innovative applications of natural products chemistry for health applications and employed genetic engineering strategies to optimize the therapeutic protein-production capabilities of plants.

In 2024, Vargas Ulloa was accepted into the Regenerative Sciences Ph.D. track, Mayo Clinic Graduate School of Biomedical Sciences. She joined the Functional Epigenomics Lab in 2025.

Vargas Ulloa's research focuses on understanding the role of transcription factors in the development of endometrial cancer, with a focus on health disparities. She is a Klesch Fellow in Regenerative Medicine.

  • Yiwen Xie
  • Ph.D. student, Biochemistry and Molecular Biology track, Mayo Clinic Graduate School of Biomedical Sciences (2023-present)

Xie received his Bachelor of Science degree in biochemistry and molecular biology in 2020 from the University of Massachusetts Amherst. He earned a master's degree in biotechnology in 2022 from Northwestern University in Chicago, Illinois.

Xie joined the Functional Epigenomics Lab in 2023. He has been using bioinformatic tools to analyze transposable elements in ovarian cancer at the single cell level and identify novel master regulators of chemotherapy resistance.