Stephen H. Tsang, M.D, Ph.D. is an acclaimed clinical geneticist in the care of individuals with retinal degenerations. He has been culturing stem cells since 1992 and created the first mouse model for a recessive form of retinitis pigmentosa (RP) by applying genome engineering to stem cell technology in 1995. He successfully treated preclinical models of Pde6a, Pde6b, Mfrp, Rho, Cngb1 and autosomal recessive bestrophin retinopathies.

He has expertise in designing and testing genome engineering strategies in pre-clinical models, developing patient-specific knock-in models, generating of patient cell lines and providing care to patients with a precision medicine approach. He is also leading efforts in FDA trials for gene therapies, including PDE6A, RAB geranylgeranyl transferase, RPGR, CNGB3, CNGA3 and ABCA4 retinopathies.

He wrote 3 books: "Precision Medicine, CRISPR, and Genome Engineering: Moving from Association to Biology and Therapeutics" and "Stem Cell Biology and Regenerative Medicine in Ophthalmology", Springer Press, NY; and "CRISPR Genome Surgery in Stem Cells and Disease Tissues", Elsevier Inc. He is an elected member of several honorary societies including the American Society for Clinical Investigation, Alcon Research Institute and American Ophthalmological Society. He is consistently named to various NIH study sections (DPVS standing member 2014-8 and PED2 2022-6) and other review committees; Alcon Research Institute Grant Review Committee (2022-27), Scientific Advisory Panel - Research to Prevent Blindness (RPB, 2019-29), Chair of American Ophthalmological Society Thesis Review Committee (2022-2023). Many of his publications are in widely-read general interest journals such as Science, NEJM, Lancet, Cell Stem Cell, Nature Genetics, and Journal of Clinical Investigation, which attests to the broad impact that his work has had.

Dr. Tsang received a resident teaching award in 2008 and was the Columbia Ophthalmology Basic Science Course Director (2006-2018).

Dr. Tsang graduated from Johns Hopkins University, where he began his medical genetics training under the tutelage of Professor Victor A. McKusick. He received his M.D. and Ph.D. degrees from the NIH-National Institute of General Medical Sciences Medical Scientist Training Program (MSTP) at Columbia University. Dr. Tsang then completed his residency at Jules Stein Eye Institute/UCLA, followed by studies with Professors Alan C. Bird and Graham E. Holder on improving the care of individuals with macular degenerations.