Principal Investigator

HUNGOO LEE

Assistant Professor at Johns Hopkins School of Medicine (from Sep. 2024)

He has been studying molecular mechanisms of epigenetic abnormalities by the expanded long tandem repeats in Fragile X syndrome. During his Postdoc in Dr. Jeannie Lee’s lab at Harvard Medical School, he identified the molecular mechanisms that can induce the shortening of the pathogenic long tandem repeats in Fragile X patient cells. Before his postdoc, he earned his Ph.D. in epigenetics and molecular biology in the laboratory of Dr. Vincenzo Pirrotta, where his dissertation work focused on the genome-wide epigenetic regulatory roles of Polycomb group proteins and Trithorax group proteins especially at the intergenic regions. Before his Ph.D., he worked as a computational biologist at Dong-a Seetech IT company and studied a condition-specific transcriptional regulatory network in yeast. By combining his diverse background in computational biology, epigenetics, and molecular biology, he plans to tackle the diverse repeat expansion diseases including Huntington's, Myotonic Dystrophy, Friedreich's ataxia, ALS, and other autism spectrum disorders by understanding why the patients show increased repeat instability.

Contact: hlee308 at jh dot edu
Miller Research Building Room 449

RUOYAN PU

Research Technologist

M.Sc. Biomedical Engineering, Johns Hopkins University
B.S. Neuroscience, Simmons University

She is interested in the epigenetic changes associated with neurological disorders, including Autism spectrum disorders (ASD) and Alzheimer’s disease (AD). Her research also focuses on the use of induced pluripotent stem cells (iPSCs), and explores their applications in disease modeling. Previously, she investigated the correlation between COVID-19 infection and Alzheimer’s disease pathology using the iPSC model. She joined H. Lee lab to study repeat expansion disorders (REDs) and explore potential therapeutic methods for these diseases.


SHREYAN URHEKAR

Research Assistant

M.Sc. Biotechnology, Johns Hopkins University
Bachelor of Technology in Biotechnology, D. Y. Patil University

He is interested in understanding the molecular basis of CGG repeat expansion disorders, particularly in fragile X syndrome, by applying a diverse combination of technologies from immunology, biophysical characterization, and iPSCs. Previously, he worked on biophysical characterizations of proteins in the ubiquitin-proteasome pathway and studied the molecular dynamics of pioneer factors in histone methylation patterns. He joined the H. Lee lab to further explore repeat expansion disorders (REDs) and contribute to developing potential therapeutic strategies

DENA SAGHAI MAROOF

PhD Student (Human Genetics and Genomics)

B.S Biology, University of Virginia

She is interested in identifying RNA-mediated epigenetic mechanisms driven by repeat expansions in neurological disease with a focus on amyotrophic lateral sclerosis (ALS). Her work examines the interplay between R-loops, G-quadruplex structures, and epigenetic modifications using computational and experimental approaches. Previously, she sought to unravel the genetic architecture of type 1 diabetes and molecular mechanisms of cystic fibrosis.

She joined the H. Lee laboratory to study repeat expansion-mediated pathology in ALS and to integrate insights across repeat expansion disorders for therapeutic development.

SOOJI PARK

Postdoctoral Fellow

Ph.D. Biomedical Sciences, Korea University
B.S. Life Science, Kyonggi University

She has developed a strong foundation in molecular biology and genome engineering, with a particular focus on advancing CRISPR-based technologies. During her doctoral training, she designed CMP-PE-V1 and eCas12f1, enabling more efficient and versatile manipulation of genomic targets. She applied these CRISPR tools across diverse biological contexts, including genome editing, transcriptional regulation, targeted cancer therapy, and mouse disease models.

She joined the H. Lee lab as a postdoctoral fellow to extend her research into the biology of DNA repeat expansion disorders (REDs). Her current work leverages CRISPR-based genome engineering to generate diverse cellular models for systematically analyzing repeat expansion and contraction. Through these models, she aims to identify key genetic and epigenetic factors that drive repeat instability and to elucidate the underlying molecular mechanisms.

With a particular interest in REDs associated with autism spectrum disorders (ASD), her long-term research goal is to integrate genome engineering, epigenetics, and stem cell biology to uncover fundamental principles of repeat instability and to translate these insights into precise and effective therapeutic strategies for currently incurable disorders.

Lab Members