Hungoo Lee is an assistant professor in the Department of Genetic Medicine at Johns Hopkins School of Medicine. He studies the molecular mechanisms of epigenetic abnormalities caused by expanded long tandem repeats in Fragile X-associated diseases and other repeat expansion diseases. By leveraging his diverse background in computational biology, epigenetics, and molecular biology, he identified an R-loop, a non-canonical nucleic acid structure formed by RNA and DNA hybrid, as an important mechanism for regulating repeat expansion/contraction in Fragile X syndrome (FXS).He aims to investigate the root cause of increased repeat instability in multiple Repeat Expansion Diseases including Fragile X syndrome and FXTAS, and ALS.